Identification of Arctic char stocks in the Cambridge Bay Area, Nunavut Territory,
and evidence of stock mixing during overwintering
by
Allan H. Kristofferson
submirted to the tåJil'TrGraduate studies in Partial Fulfillment of the Requirements for the Degree of
Doctor of Philosophy
Department of ZoologY University of Manitoba Winnipeg, Manitoba
November,2002 THE UNIVERSITY OF MANITOBA
FACULTY OF GRADUATE STUDIES *+*** COPYRIGHT PERMISSION PAGE
IDENTIFICATION OF ARCTIC CHAR STOCKS IN THE CAMBRIDGE BAY AREA. NUNAWT TERRITORY' AND EVIDENCE OF STOCK MIXING DURING OVERWINTERING
BY
ALLAN H. KRISTOFFERSON
A Thesis/Practicum submitted to the Faculty of Graduate Studies of The University
of Manitoba in partial fulfillment of the requirements of the degree
of
Doctor of Philosophy
ALLAN H. KRISTOFFERSON @ 2OO2
Permission has granted been to the Library of The university of Manitoba to lend or sell copies of this thesis/practicum, to the National Library of Canada to microfilm this thesis and to lend orìell copies of the film, and to University Microfilm Inc. to publish an abstract of this thesis/practicum.
The author reserves other publication rights, and neither this thesis/practicum nor extensive extracts from it may be printed or otherwise reproduced without the author's written permission. I
ABSTRACT
I examined samples of anadromous Arctic char spawners from twelve locations in the Cambridge Bay area, Nunavut Territory, for evidence of stock structuring. These samples could be distinguished from one another on the basis of differences in morphologicai characters, using discriminant function analysis. Significant differences in the means of morphometric characters (ANOVA, minimum p < 0.05) were evident for most pair-wise comparisons. The morphometric characters that contributed the most to the discrimination were orbital length, maxillary width, and head depth. Discrimination among samples was less effective using meristic counts, but many significant differences were observed in pair-wise comparisons, and results paralleled those from the morphometric analysis. The meristic counts that contributed most to the discrimination were anal fin ray count, pyloric caeaa count, and upper gill raker count. There was evidence of reproductive isolation among these spawning aggregations, based on significant differences (p < 0.05, p < 0.001) in allele frequencies for Malic Enzyme between some samples of spawners.I present clear evidence of homing to natal spawning grounds based on significant differences among samples (ANOVA, minimum p < 0.05) in mean strontium (Sr) concentrations (micro-PIXE) in the eariy growth regions of otoliths of spawners. The consistency of the Sr concentrations among all age groups within each sampie of spawners is evidence of philopatry. I conclude that anadromous Arctic char in the study area home to a high degree and have formed discrete stocks, both within and between river systems. Samples of nonspawning Arctic char captured in autumn upstream migrations as they returned to fresh water showed considerable heterogeneity in morphometric characters (cluster analysis and discriminant function analysis) and otolith Sr concentrations in the early growth regions. This is evidence that these upstream migrations are composed of an admixture of stocks. Nonsatisfaction of Castle-Hardy-V/einberg equilibrium (Malic Enzyme, heterozygote deficiency) in one sample provides additional evidence of mixing of stocks during this overwintering migration.The Arctic char is very important to the economy of the Inuit of the study area and is harvested regularly.Threats to the genetic diversity of this species, contained within the aggregate of these discrete stocks, include habitat destruction and harvest. In order to preserve the genetic diversity of individual stocks, an effective management strategy must be developed and implemented. I present an "Adaptive Management" approach for future consideration. This approach utilizes the traditional ecological knowledge of the resource users, in particular the location of spawning grounds, and couples it with the biological complexities of this species. Harvest plans need to be developed, based on this information, so that individual stocks can be harvested at a level that will not adversely affect the genetic diversity of the species. u
TABLE OF CONTENTS page
ABSTRACT..... i
TABLE OF CONTENTS.
ACKNOWLEDGEMENTS....
LIST OF FIGURES...... vi
LIST OF TABLES...... xvii
INTRODUCTION. I
I The Arctic char.. I
Life historY. 3
Humans and Arctic char.. 6
The stock. 6
Study objectives. I
MATERIALS AND METHODS...... 10
The study area.. 10
Geography and geology 10
The community of Cambridge Bay.. 12
The fishery 13
Sampling locations and sample collection. 14
Ekaltuk River. 15
Paliryuak (Suney) River. 20
Halovik (Thirry Miie) River. 22
Lauchlan River (Byron Bay.. 24
Javco River. 26 iii
Ellice River. 29
Kitiga Lake. 31
Freshwater Creek. 31
Anderson Bay Lake. 34
Biological variables examined. 36
Morphometric measurements. 36
Meristic counts. 40
Genetic analysis. 40
Electrophoresis. . 40
Mitochondrial DNA (mtDNA). 4I
Stable isotope analysis. 43
Micro-PIXE analysis of otolith strontium concentrations. . . 44
Data analysis. .. . 48
RESULTS ...... 52
Comparison of spawning samples...... 52
Discriminant function analysis. 52
Examination of upstream migrations... 86
Cluster analysis. 86
Comparison of samples of spawners and nonspawners using meristics...... I44
Genetic analysis. 158
Electrophoresis.. 158
Mitochondrial DNA (mtDNA). 164
Stable isotope analysis. 167 iv
Micro-PIXE analysis of otolith strontium concentrations. . . r69
DISCUSSION... 183
Evidence of stock structuring 183
Morphology...... 183
Genetics. 189
Stable isotopes. 196
Homing. 199
Evidence of mixing during overwintering... 207
The upstream migration. 207
Heterogeneity in genetics, morphology and otolith strontium
concentrations in samples from upstream migrations... 208
Advantages of mixing during overwintering... 2t0
Population richness of anadromous Arctic char.. 212
Implications for management. 2r3
Traditional management..... 2I4
Conventional management.... 217
Comanagement. 220
Adaptive management under comanagement...... 225
CONCLUSIONS. 230
REFERENCES.. 231
APPENDIX I... 253
APPENDIX II 254
APPENDIX III 255 ACKNO\ryLEDGEMENTS
great A many people have provided me with the support needed to carry out this study. I would like to-begin by thanking the Inuit of CamUiiAge Bay for very willingly sharing their knowledge of Arctic char with me, particularly the loóation, oi rpu*"rr. Without this information, the study would not have been póssible. Individuals include Bill Lyall, David Kaomayok, the ohokannoak family, *à Mor.s Koihok. I thank my supervisor, Dr. Kenneth Stewart, for his guidance, advice, stimulation, wisdom, humour and patience throughout the rather long geitation period ofthis work. He was always there when I needed him. I thank my aavisory ,o**iu." members, Dr. Drew Bodaly, Dr. Fikret Berkes and Dr. Mark Abrahams for their advice, constructive criticisms and reviews of this work . I also thank Dr. Geoffrey power for acting as external examiner. The Department of Fisheries and Oceans has supported this project from the beginning. From that organizationl would like to thankRobert Moshenko and Roger Peet and Drs' Burt Ayles and Redmond Clarke for providing me with the opporhrnity to pursue this endeavour, and to Larry de March for continued support. Gary ðãrder and Dale McGowan provided essential support in the field and the lâ¡ and toihem I will be forever grateful. I thank John Babaluk for inhoducing me to the world of micro-plXE and for that he has my everlasting gratitude. Others who helped with field and laboratory work include George Low, Burt Hunt, Lianne Postma, Jennifer Brown Gladden, Theresa Carmichael, Fred Hn¡ka, Len Andrusiak, Jim Johnson, Rick Wastle and the students. Dr. Ray Hesslein and Dr. Pat Ramlal helped with the stable isotope analysis. Dan Topolniski, Peter Thompson, Patt Hall, Judy Freeman and Don Dowler piovided plenty of encoruagement when needed. Ron Hempel and Chelsey Booth providìd kéy support with figures and typing. Margaret Koshinsky and Ron Bretecher from North/South did an excellent job with the morphology. Dr.Norman Halden and Sergio Mejia from the Department-gil of Geological Sciences, University of Manitoba, and Dr. Ian Campbell an¿ Teesdale from the Department of Physics, University of Guelph , providèd key support for the micro-PIXE analysis, and I thank all of them I would like to extend a special thanks to Dr. Lionel Johnson for many stimulating discussions about Arctic char and to Dr. Casimir Lindsey, a former mentor, ior his faith in my ability. Finally, I would like to thank my wife Arleen for putting up with me for all these years and believing in me when I most needed it. Without her support I could not have done this. vi
LIST OF FIGURES
page Figure 1. Distribution of Arctic char in North America, and worldwide, after Scott and Crossman1973. Johnson 1980 2
Figure 2. Map of the study area showing locations of river systems sampled. i1
Figure 3. Map of the Ekalluk River drainage basin showing sampring locations of Arctic char spawners at Lady pelly in 19g7, Wishbone Lake in 1994 and Ferguson Lake in 1996. Upstream migrants were sampled at the mouth of the Ekalluk River (1988, 1990,1991,1992,1993,1994) where it empties into V/ellington Bay.. 1g
Figure 4. Map of the Paliryuak River drainage basin showing sampling locations of Arctic char spawners in 1987 and the l99Z commercial gillnet fishery 21
Figure 5. Map of the Halovik River drainage basin showing sampling locations of Arctic char spawners at Halovik Lake 1987 and 1993, the weir site, and the sampling location of the 1992 upstream migration z)
Figure 6. Map of the Lauchlan River drainage basin showing the sampling location of Arctic char spawners in 1987, and the sampling location attheI992 and the1996 commercial eillnet fisheries 25
Figure 7. Map of the Jayco River drainage basin showing the sampring location of the 1990 upstream migration of Arctic char at the wetr. 2l
Figure 8. Map of the drainage basin showing sampling locations of Arctic char spawners at Char and Fish Trap lakes in 1991 ...... 2g
Figure 9. Map of the Ellice River drainage basin showing sampling location of Arctic char at thel990 commercial gillnet fishery... 30
Figure 10. Map of the Kitiga Lake drainage basin showing sampling location of Arctic char spawners in 1994 J¿ vIl
Figure 1 1. Map of the Freshwater creek drainage basin showing sampling locations of Arctic char spawners at Mount pelly Lake 1992 and 1993, and the weir site where the upstream migration was aa sampled in 1988, 199i and 1994.. JJ
Figure 12. Map of the Anderson Bay Lake drainage basin showing sampling location of Arctic char spawners at Anderson Bay Lake in 1994. The 1993 sample location is not known 35
Figure 13. The morphological variables examined in this study. 3g
Figure 14. Diagram of Scanning Proton Microprobe used in micro-plXE analysis 45
Figure 15. Discriminant function analysis of morphometric measurements of Arctic char spawners from Ferguson, Lady pelly and Wishbone lakes in the Ekalluk River system. 54
Figure 16.4 comparison of mean log (a) orbital length (OOL), (b) maxillary width (MXW), and (c) lower gill arch length (LAL) among samples of Arctic char spawners from Lady Pelly, Wishbone and Ferguson lakes 56
Figure 17. A plot of log orbital length (ool) againsr log maxillary width (MXW) for Arctic char spawners from Lady pelly, Wishbone and Ferguson lakes 57
Figure 18. A plot of log orbital length (ool) against age for Arctic char spawners from Lady Pelly, V/ishbone and Ferguson lakes...... 59
Figure i9. Discriminant function analysis of morphometric measurements of Arctic char spawners from Halovik Lake 1987, Halovik Lake 1993, Kitiga Lake and Ferguson Lake 60
Figure 20. A comparison of mean log (a) orbital length (OOL), (b) maxillary width (N4XW), and (c) caudal peduncle lengrh (CpL) among samples of Arctic char spawners from Halovik Lake 1987, Halovik Lake 1993, Kitiga Lake and Ferguson Lake...... 62
Figure 21. A plot of log orbital length (ool) against log maxillary width (MXUD for Arctic char spawners from Halovik Lake 1987, Halovik Lake 1993, Kitiga Lake and Ferguson Lake 63 vlll
Figure 22. Discriminant function analysis of morphometric measurements of Arctic char spawners from Kitiga Lake, Mount pelly Lake 1992,and Anderson Bay Lake 1994. 65
Figure 23. A comparison of mean log (a) pectoral fin length (pCL), (b) dorsal length (DOL), and (c) gill raker length (GRL) among samples of Arctic char spawners from Kitiga Lake, Mount Pelly Lake 1992, and Anderson Bay Lake 1994. 67
Figure 24. Aprot of log dorsal length (DoL) againsr log gill raker length (GRL) for Arctic char spawners from Kitiga Lake, Mount Pelly Lake 1992, and Anderson Bay Lake 1994 68
Figure 25. Discriminant function analysis of morphometric measurements of Arctic char spawners from Mount Pelly Lake 1992 and 1993, and Anderson Bay Lake 1993 and T994 69
Figure 26. A comparison of mean log (a) head depth (HDD), (b) body depth (BDD), and (c) pectoral fin length (pCL) among samples of Arctic char spawners from Mount Pelly Lake 1992 and, 1993, and Anderson Bay Lake i993 and 1994.. 71
Figure 27.Aplot of log head depth (HDD) against log body depth (BDD) for Arctic char spawners from Mount Pelly Lake 1992 and 7993, andAnderson Bay Lake 1993 and 1994 73
Figure 28. Discriminant function analysis of morphometric measurements of Arctic char spawners from Anderson Bay Lake 1993 and 1994, Char Lake and Fish Trap Lake. 'tAta
Figure 29. A comparison of mean log(a) body depth (BDD), (b) head depth (HDD), and (c) orbital length (OOL) among samples of Arctic char spawners from Anderson Bay Lake 1993 and |gg4, Char Lake and Fish Trap Lake. 76
Figure 30. A plot of log head depth (HDD) against log body depth (BDD) for Arctic char spawners from Anderson Bay Lake 1993 and 1994, Char Lake and Fish Trap Lake. 77
Figure 31.4 comparison of mean log (a) orbital length (OOL), (b) maxillary width (MXUD, and (c) head depth (HDD) among the twelve samples of Arctic char spawners examined across the study area.. 80 ix
Figure 32. A dendrogram of Squared Mahalanobis Distances showing morphological relationships among the samples of Arctic char spawners exammecl 84
Figure 33. Cluster analysis of morphometric measurements from two known groups of spawners (Ferguson Lake and Lady Pelly Lake 88
Figure 34. Cluster analysis of morphometric measurements of Arctic char in the 1988 upstream migration in the Ekalluk River. Cluster D is considered to represent a group in this analysis but clusters F, G and H could possibly represent separate groups as well.. .. 90
Figure 35. Discriminant function analysis of morphometric measurements of Arctic char from three spawning aggregations (Lady Pelly, Wishbone and Ferguson lakes) and the sample of nonspawning Arctic char from the 1988 upstream migration in the Ekalluk River 91
Figure 36.4 comparison of mean log (a) gill raker length (GRL), (b) maxillary width (MXSD, and (c) orbital length (OOL) among samples from three spawning aggregations in the Ekalluk River system (Lady Pelly, Wishbone and Ferguson lakes) and the sample of nonspawning Arctic char from the 1988 upstream migration in the Ekalluk River 93
Figure 37. A plot of log maxillary width (MXVD against log gill raker length (GRL) for Arctic char spawners from three spawning aggregations in the Ekalluk River system (Lady Pelly, Wishbone and Ferguson lakes) and the sample of nonspawning Arctic char from the 1988 upstream migration in the Ekalluk River 9s
Figure 38. Cluster analysis of morphometric measurements of Arctic char from the i990 upstream migration in the Ekalluk River. Cluster G is considered to represent a group in this analysis.. ... 96
Figwe 39. Discriminant function analysis of morphometric measurements of Arctic char from three spawning aggregations in the Ekalluk River system (Lady Pelly, Wishbone and Ferguson lakes) and the sample of nonspawning Arctic char from the 1990 upstream migration in the Ekalluk River 97 Figure 40. cluster analysis of morphometric measurements of Arctic char from the 1991 upstream migration in the Ekalluk River. Cluster F is considered to represent a group in this analysis...... 98
Figure 41. Discriminant function analysis of morphometric measurements of Arctic char from three spawning aggregations in the Ekalluk River system (Lady Pelly, Wishbone and Ferguson lakes) and the sample of nonspawning Arctic char from the 1991 upstream migration in the Ekalluk River. 99
Figure 42. cluster analysis of morphometric measurements of Arctic char from the 1992 upstream migration in the Ekalluk Rive Cluster J is considered to represent a group in this analysis. 100
Figure 43. Discriminant function analysis of morphometric measurements of Arctic char from three spawning aggregations in the Ekalluk River system (Lady Pelly, Wishbone and Ferguson lakes) and the sample of nonspawning Arctic char from the 1992 upstream migration in the Ekalluk River. I02
Figure 44. Cluster analysis of morphometric measurements of Arctic char in the 1993 upstream migration in the Ekalluk River. Cluster F is considered to represent a group in this analysis 103
Figure 45. Discriminant function analysis of morphometric measurements of Arctic char from three spawning aggregations in the Ekalluk River system (Lady Pelly, Wishbone and Ferguson lakes) and the sample of nonspawning Arctic char from the igg3upstream migration in the Ekalluk River. 104
Figure 46. Cluster analysis of morphometric measurements of Arctic char from the 1994 upstream migration in the Ekalluk River. Cluster F is considered to represent a group in this analysis ...... 1 05
Figure 47. Discriminant function analysis of morphometric measurements of Arctic char from three spawning aggregations in the Ekalluk River system (Lady Pelly, V/ishbone and Ferguson lakes) and the sample of nonspawning Arctic char from the 1994 upstream migration in the Ekalluk River. 106 xr
Figure 48. A comparison of mean log (a) pectoral fin length (PCL), (b) maxillary width (I\,D(W), and (c) orbital length (OOL) among samples from three spawning aggregations in the Ekalluk River system (Lady Pelly, Wishbone and Ferguson lakes) and the sample of nonspawning Arctic char from the 1994 upstream migration in the Ekalluk River. 109
Figure 49. A plot of log maxillary width (lv{X\Ð against log pectoral fin length (PCL) for Arctic char spawners from three spawning aggregations in the Ekalluk River system (Lady Pelly, Wishbone and Ferguson lakes) and the sample of nonspawning Arctic char from the 1994 upstream migration in the Ekalluk River. 110
Figure 50. Discriminant function analysis of morphometric measurements of Arctic char from three spawning aggregations in the Ekalluk River system (Lady Pelly, Wishbone and Ferguson lakes) and the samples of nonspawning Arctic char from the 1988 and 1994 upstream migrations in the Ekalluk River. 111
Figure 51 . A comparison of mean log (a) orbital length (OOL), (b) gill raker length (GRI), and (c) maxillary width (MXSD among samples from three spawning aggregations in the Ekalluk River system (Lady Pelly, Wishbone and Ferguson lakes) and the samples of nonspawning Arctic char from the 1988 and 1994 upstream migration in the Ekalluk River. 113
Figwe 52. A plot of log maxillary width (MXW) against log gill raker length (GRL) for Arctic char spawners from three spawning aggregations in the Ekalluk River system (Lady Pelly, Wishbone and Ferguson iakes) and the samples of nonspawning Arctic char from the 1988 and 1994 upstream migration in the Ekalluk River. TT4
Figure 53. Cluster analysis of morphometric measurements of Arctic char from the 1992 upstream migration in the Halovik River. Cluster D is considered to represent a group in this analysis. . ... r17
Figure 54. Discriminant function analysis of morphometric measurements of Arctic char from spawning aggregations taken in Halovik Lake 1987 and Halovik Lake 1993 and a sample of nonspawning Arctic char from the 1992 upstream migration in the Halovik River. 118 xii
Figure 55. A comparison of mean log (a) body depth (BDD), (b) caudal peduncle depth (CPD), and (c) maxillary width (MXW) among samples of Arctic char spawners from Halovik Lake 1987 and Halovik Lake 1993 and a sample of nonspawning Arctic char from the 1992 upstream migration in the Halovik River. .. 120
Figure 56. A plot of log body depth (BDD) against log maxillary width (MXW) for Arctic char spawners from Halovik Lake 1987 and Halovik Lake 1993 and a sample of nonspawning Arctic char from the 1992 upstream migration in the Halovik River. .. I22
Figure 57. Cluster analysis of morphometric measurements of Arctic char from the 1992 upstream migration in the Lauchlan River. Cluster B is considered to represent a group in this analysis..... I23
Figure 58. Cluster analysis of morphometric measurements of Arctic char from the commercial eillnet fishery at the Lauchlan River in July 1996 t24
Figure 59. Cluster analysis of morphometric measurements of Arctic char from the commercial gillnet fishery at Paliryuak River in July 1992. Cluster N could represent a group. r25
Figure 60. Cluster analysis of morphometric measurements of Arctic char from the 1988 upstream migration into Freshwater Creek 1988. Cluster O could represent a group. t28
Figure 6 i . Discriminant function analysis of morphometric measurements of Arctic char from spawning aggregations taken in the Freshwater Ceek system (Mount Pelly Lake 1992 and 1993) and a sample of nonspawning Arctic char from the i988 upstream migration in Freshwater Creek t29
Figure 62. Discriminant function analysis of morphometric measurements of Arctic char from spawning aggregations taken in the Freshwater Creek system (Mount Peliy Lake 1992 and 1993) and different clusters (Fig. 60) of the 1988 upstream migration. The comparisons are: (a) Cluster J, (b) Cluster K, (c) Cluster O, and (d) Clusters E, G, P, D and 8..... 130
Figure 63. Cluster analysis of morphometric measurements of Arctic char from the 1991 upstream migration into Freshwater Creek. Clusters C, E and F could represent different groups. 131 xlll
Figure 64. Discriminant function analysis of morphometric measurements of Arctic char from spawning aggregations taken in the Freshwater Creek system (Mount Pelly Lake 1992 and 1993) and different clusters (Fig. 63) of the i991 upstream migration. The comparisons are: (a) Cluster C, (b) Cluster D, (c) Cluster E, and (d) Cluster F 133
Figure 65. Cluster analysis of morphometric measurements of Arctic char from the upstream migration into Freshwater Creek 1994. Clusters M and N could represent different groups. 134
Figure 66. Discriminant function analysis of morphometric measurements of Arctic char from spawning aggregations taken in the Freshwater Creek system (Mount Pelly Lake 1992 and 1993) and a sample of nonspawning Arctic char from the 1994 upstream migration in Freshwater Creek 135
Figure 67. Cluster analysis of morphometric measurements of Arctic char from the 1990 upstream migration in Jayco River. Cluster D could represent a group. 136
Figure 68. Discriminate function analysis of morphometric measurements of Arctic char from spawning aggregations taken in Char Lake and Fish Trap Lake in 1991 and a sample of nonspawning Arctic char from the 1990 upstream migration in Jayco River... 138
Figure 69. A comparison of mean log (a) head depth (HDD), (b) trunk length (TTL), and (c) body depth (BDD) among samples of Arctic char spawners from Char Lake and Fish Trap Lake in 1991 and a sample of nonspawning Arctic char from the 1990 upstream migration in Jayco River. 140
Figure 70. A plot of log trunk length (TTL) against log head depth (HDD) for Arctic char spawners from Char Lake and Fish Trap Lake in 1991 and a sample of nonspawning Arctic char from the 1990 upstream migration in Jayco River. I4l
Figure 71 . Cluster analysis of morphometric measurements of Arctic char taken by the 1990 commercial gillnet fishery at Ellice River. Cluster F could represent a group. 142 xlv
Figure 72. Discriminant function analysis of morphometric measurements of Arctic char from spawning aggregations taken in Mount Pelly Lake 1992 and Anderson Bay Lake in 1993 andl994, and a sample of nonspawning Arctic char taken by the 1990 commercial gillnet fishery at Ellice River. 143
Figure 73. A comparison of mean log (a) head depth (HDD), (b) body depth (BDD), and (c) pectoral fin length (PCL) among samples of Arctic char from spawning aggregations taken in Mount Pelly Lake 1992 and Anderson Bay Lake in 1993 and 1994, and a sample of nonspawning Arctic char taken by the 1990 commercial gillnet fishery at Ellice River. 146
Figure 74.Aplot of log head depth (HDD) against log body depth (BDD) for samples of Arctic char from spawning aggregations taken Mount Pelly Lake 1992 and Anderson Bay Lake in 1993 and 1994, and a sample of nonspawning Arctic char taken by the 1990 commercial gillnet fishery at Ellice River. 141
Figure 75. Discriminant function analysis of meristic counts from samples of Arctic char spawners from the Ekalluk River system (Ferguson, Lady Pelly and V/ishbone lakes). 148
Figure 76. A comparison of (a) anal fin ray count (ARC), (b) pelvic fin ray count (VRC), and (c) pyloric caecacount (PYL) between samples of Arctic char spawners from the Ekalluk River system (Ferguson, Lady Pelly and Wishbone lakes). 150
Figure 77 . A comparison of (a) anal fin ray count (ARC), (b) pyloric caeca count (PYL), and (c) upper gill raker count (UGR) among the twelve samples of Arctic char spawners examined... 152
Figure 78.4 comparison of (a) anal fin ray count (ARC), (b) upper gill raker count (UGR), and (c) lower gill raker count (LGR) among the six samples of nonspawning Arctic char taken in the upstream migration in the Ekalluk River (1988, 1990,I99T, t992,1993,1994). 156
Figure 79.4 comparison of (a) anal fin ray count (ARC), (b) branchiostegal ray count (BRC), and (c) pectoral fin ray count (PCR) among the six samples of nonspawning Arctic char taken in the upstream migration in the Ekalluk River (i988, 1990, r99r, 1992, 1993, 1994) t57 Figure 80. The 352 base sequence of the mitochondrial DNA control region adjacent to the tRNA Proline gene for Arctic char examined in this study. Haplotype 1 is displayed with an asterisk indicating the variable base position. The short segment (10 bases) indicates the difference with Haplotypes 2 and 3 r66
Figure 81. Carbon and nitrogen isotopes in Arctic char taken from the upstream migration in (a) Jayco River 1990, (b) Ellice River 1990, (c) Char Lake spawners 1991, (d) the upstream migration in the Halovik River 1992, and (e) the upstream migration in the Ekalluk River 1992 168
Figure 82. Sulfur and nitrogen isotopes in Arctic char taken from the upstream migration in (a) Jayco River 1990 and (b) Char Lake spawners 1991 170
Figure 83. The relationship between strontium in water samples taken at the spawning grounds and strontium in the early growth regions of otoliths of Arctic char spawners captured there T7l
Figure 84. The four distinct patterns of strontium concentrations from the centre of the otolith to its outer edge as revealed by micro- PIXE line scans. The pattern in (a) is from an anadromous Arctic char, (b) is from an anadromous Arctic char showing the maternal effect in the early growth zone, (c) is from a nonanadromous Arctic char and (d) is from a nonanadromous Arctic char showing the "matemal effect" in the early growth zone.. 173
Figure 85. A comparison of the percent of spawners displaying the "maternal effect" of strontium concentrations in the otolith primordia with the distance of the spawning ground from the sea... 175
Figure 86. A plot of mean strontium concentration in the early growth region of the otolith against age for samples of Arctic char spawners. n9
Figure 87. A comparison of frequency distributions of strontium concentration in the early growth region of the otolith among samples of Arctic char spawners.... 181 xvl
Figure 88. A comparison of mean strontium concentration in the early growth region of the otolith against age among samples of Arctic char spawners from the Ekalluk River system and samples of Arctic char from the six upstream migrations into
the Ekalluk River ( 1 98 8, 1990, 1991, 1992, 1993, 199 4) r82 xvll
LIST OF TABLES
Page Table 1. A summary of the sampling details for the collection of Arctic char spawners.... 16
Table2. A summary of the sampling details for the collection of nonspawning Arctic char t7
Table 3. Summary of starch gel electrophoresis protocols used on Arctic char samples 42
Table 4. Sex ratios of Arctic char spawners by capture location. s2
Table 5. Summary of the discriminant frrnction analysis of morphometric measurements of Arctic char spawners from Lady Pelly, V/ishbone and Ferguson lakes 55
Table 6. Summary of the discriminant function analysis of morphometric measurements of Arctic char spawners from Halovik Lake 1987, Halovik Lake 1993, Kitiga Lake, and Fersuson Lake 6l
Table 7 . Summary of the discriminant function analysis of morphometric measurements of Arctic char spawners from Kitiga Lake, Mount Pelly Lake 1992, and Anderson Bay Lake r994 66
Table 8. Summary of the discriminant function analysis of morphometric measurements of Arctic char spawners from Mount Pelly Lake 1992 and 1993, and Anderson Bay Lake 1993 and 1994 70
Table 9. Summary of the discriminant function analysis of morphometric measurements of Arctic char spawners from Anderson Bay Lake 1993 and 1994, Char Lake and Fish Trap Lake 75
Table 10. Summary of the discriminant function analysis of morphometric measurements of Arctic char from the twelve samples of spawners examined across the study ar:ea.. 7g xvlll
Table i 1. A comparison of ali pairs of means for the morphometric measurement log orbital length (OOL) among the twelve samples of Arctic char spawners examined across the study area, using the Least Significant Difference (LSD) test... g1
Table 12. A comparison of all pairs of means for the morphometric measurement log maxillary width (NDilÐ among the twelve samples of Arctic char spawners examined across the study area, using the Least Significant Difference (LSD) test... gz
Table 13. A comparison of all pairs of means for the morphometric measurement log head depth (HDD) among the twelve samples of Arctic char spawners examined across the study area, using the Least Significant Difference (LSD) test... g3
Table 14. A comparison of squared Mahalanibis Distances among the twelve samples of Arctic char spawners examined across the study area 85
Table 15. Location and year of upstream migration of Arctic char examined by cluster analysis. g7
Table 16. Summary of the discriminant function analysis of morphometric measurements of Arctic char from three spawning aggregations in the Ekalluk River system (Lady Pelly, Wishbone and Ferguson lakes) and a sample of nonspawning Arctic char from the 1988 upstream migration in the Ekalluk River 92
Table 17. Summary of the discriminant function analysis of morphometric measurements of Arctic char from three spawning aggregations in the Ekalluk River system (Lady Pelly, Wishbone and Ferguson lakes) and a sample of nonspawning Arctic char from the 1994 upstream migration. In the Ekalluk River r07
Table 18. Summary of the discriminant function analysis of morphometric measurements of Arctic char from three spawning aggregations in the Ekalluk River.system (Lady Pelly, Wishbone and Ferguson lakes) and samples of nonspawning Arctic char from the 1988 and 1994 upstream migrations in the Ekalluk River t12 xlx
Table 19. A comparison of Squared Mahalanobis Distances among samples of Arctic char spawners from the Ekalluk Rivei system (Lady Pelly, Wishbone and Ferguson lakes), Halovik Lake 1987 and 1993, and Kitiga Lake, and the six samples of nonspawning Arctic char from the upstream migrations in the Ekalluk River (1988, 1990, t991, tgg2, 1993 and tgg4)...... 116
TabIe20. Summary of the discriminant function analysis of morphometric measurements of Arctic char from spawning aggregations taken in Halovik Lake 1987 and 1993, and a sample of nonspawning Arctic char from the 1992 upstream migration in the Halovik River 119
Table2l. A comparison of Squared Mahalanobis Distances among samples of Arctic char spawners from the Ekalluk River system (Lady Pelly, Wishbone and Ferguson lakes), Halovik Lake 1987 and 1993, and Kitiga Lake, and the samples of nonspawning Arctic char that were taken at paliryuak River I992,Halovik River 1992, Lauchlan River 1992 andlauchlan River 1996 127
Table22. Summary of the discriminant function analysis of morphometric measurements of Arctic char spawners from Char Lake and Fish Trap Lake, and a sample of nonspawning Arctic char from the 1990 upstream migration in Jayco River... r3g
Table23. Summary of the discriminant function analysis of morphometric measurements of Arctic char spawners from Mount Pelly Lake 1992, Anderson Bay Lake 1993 and Anderson Bay Lake 1994, and a sample of nonspawning Arctic char taken by the 1990 commercial fishery at Ellice Rivèr...... r45
Table24. Summary of the discriminant function analysis of meristic counts of Arctic char spawners from the Ekalluk River System (Lady Pelly, Wishbone and Ferguson lakes).
Table25. Pair-wise comparisons of the mean values of the meristic variable anal fin ray count (ARC) among the twerve samples of Arctic char spawners examined across the study area, using the Least Significant Difference (LSD) test... 153
Table26. Pair-wise comparisons of the mean values of the meristic variable pyloric caeca count (PYL) among the twelve samples of Arctic char spawners examined across the study ar.u, .riirrg the Least Significant Difference (LSD) test... 154 Table2T. Pair-wise comparisons of the mean values of the meristic variable upper gill raker count (UGR) among the twelve samples of Arctic char spawners examined across the study area, using the Least Significant Difference (LSD) test... 155
Table 28. Samples of Arctic char spawners and nonspawners examined by electrophoresis. 159
Table29. Results of electrophoresis of Malic Enzyme. phenotypic frequencies and gene frequencies are shtwn as well as a test for Castle-Hardy-'Weinberg (CHW) equilibrium 161
Table 30. A comparison of gene frequencies of Malic Enzyme among samples of Arctic char.. r63
Table 31. Mitochondrial DNA haplotypes found in samples of Arctic char spawners and nonspa\ iners during this study. t65
Table32. The range,of values of the stable isotopes carbon (,,C), nitrogen (ttN), and sulfir ¡34S¡ found in Rr.ti" char from 5 different sites r67
Table 33. A summary of micro-PIXE line scans in the otoliths of Arctic char spawners examined 172
Table 34. A summary of mean strontium concentrations in the early growth regions of otoliths of Arctic char spawners examined... t77
Table 35. A comparison of mean strontium concentrations (ppm) among all samples of Arctic char spawners, using the Least Signif,rcant Difference (LSD) test 178 I
INTRODUCTION
The Arctic Char
The Arctic char, Salvelinus alpinzs (Linnaeus), is the most northerly-distributed
freshwater fish. Worldwide, it has a circumpolar distribution, including northern North
America and northern Eurasia, especially in the Scandinavian countries and parts of the
Alps. It also occurs in Iceland, Greenland and the many interspersed Arctic islands. In
North America it is found in Newfoundland, Labrador, north along the Ungava Peninsula
to Hudson Bay, the Arctic Archipelago, and west to the Mackenzie River (Fig. 1). A few
relict lacustrine populations occur west of the Mackenzie along the Yukon north slope
(Reist 1997) as well as in Quebec and the Canadian Maritime Provinces, Maine and New
Hampshire (McPhail and Lindsey 1970 Scott and Crossman 1973). In the extreme
northern areas of its range, no other freshwater fishes are present (Johnson 1980).
Across its range, the Arctic char exhibits extreme variability in meristics,
morphometry and coloration. Initially, several of these variants were named as distinct
species (Johnson 1980;Nyman 1989). Current taxonomic information indicates that the
Arctic char examined in this study are all members of a single species, Sølvelinus alpinus
(Reist T989,1997).
Arctic char occur as anadromous or nonanadromous forms throughout the species
range (Johnson 1980). Nonmigratory freshwater char occur both in lakes separated from
the sea by impassable barriers and in many lakes and rivers with access to the sea where
they live sympatrically with the anadromous form. By definitioî, anadromous refers to
migratory fishes that spend most of their lives in the sea, returning to freshwater to spawn Figure 1. Distribution of Arctic char in North America and worldwide, after Scott and Crossman (1973) and Johnson (1980). 3
(Myers !949, cited in McDowall 1987). In the case of the Arctic char, the migration to sea and back is primarily a feeding migration, and takes place on an annual basis once salinity tolerance has been attained. The term amphidromoz.¿s refers to migratory fishes whose migration from freshwater to sea, or vice versa, is not for the purpose of breeding
(Myers Ig4g).Perhaps this term better describes the searun form of Arctic char.
However, there are instances where upstream migrations of Arctic char do include
spawners. To avoid confusion in this study, Arctic char that migrate to sea to feed and
return in fall to fresh water to overwinter are referred to as anadromous. Those that live
sympatrically with the anadromous char but do not go to sea are referred to as
nonanadromous. Arctic char isolated from the sea are referred to as landlocked'
Life History
The life history of Arctic char in Canada has been described in detail by Sprules
(1952), Grainger (1953), Andrews and Lear (1956), McPhail and Lindsey (1970), Scott
and Crossman(1973), Moore and Moore (1974), Moore (I975a,I975b), Johnson (1980),
Dempson and Green (1985), Cunjak et al. (1986), Dutil (1986) and Johnson (1989). All
forms spawn in freshwater in the fall (usualiy September or October) over a gravel
substrate. Lakes are utilized in the central Canadian Arctic and the Arctic islands because
most rivers freeze completely in winter (Johnson 1980). In other areas, spawning occurs
in rivers, often because suitable lakes are not available. The males are the f,rrst to arrive
on the spawning grounds and most estabiish territories that they defend. Arriving females
are then "courted" by the males. The female digs a redd,2-3 m in diameter, in water 3-6
m deep, into which the eggs are deposited once spawning takes place. The males' 4 territorial behaviow diminishes after the last female leaves the spawning grounds although some continue to fight occasionally for several months after spawning is complete (Johnson 1980). The eggs incubate under the ice for a period of about six months. After hatching in spring, the young char spend their early iife entirely in fresh water.
Arctic char are carnivorous, the young feeding on amphipods and insect larvae, and the adults on small fish and bottom organisms, including gastropods and chironomid
larvae. When they reach a size of about 150-200 mm (4 or 5 years in most systems) they
make their first migration to the sea. They then continue to make an annual migration to
sea until they reach sexual maturity (Johnson i980). Feeding in the sea is along nearshore
areas and char may migrate 50-100 km from the home stream during the summer (Moore
1915b; Sekerak et al. 1976; Johnson 1980). This migratory strategy allows char access to
the much greater food resources of the marine environment, which results in a
considerable increase in growth rate compared with nonanadromous Arctic char (Moore
and Moore 1974). Depending upon geographic location and local environmental
conditions, these summer feeding forays into the sea may last from 5 to 8 weeks (Johnson
1980; Dempson and Kristofferson 1987). In the fall, all Arctic char retum to freshwater to
overwinter, to escape freezing in the sea (Johnson 1980).
Once they reach sexual maturity, at asize generally exceeding 450 mm in length,
the char are ready to spawn. In the study area, the absence of mature char in the fall
upstream migration is an indication that they do not, for the most part, make the annual
feeding migration to the sea the summer prior to spawning in the fall (Sprules 1952;
Grainger 1953; Johnson 19S0). In fact, mature char can be captured on the spawning 5 grounds in freshwater in mid-sunmer. They are easily recognized as spawners by their bright red coloration. After spawning, these char remain in fresh water for another winter,
entering the sea againto feed the following stunmer. At this point, they are often very
emaciated, having lost up to 30-40Yo of their body weight as a consequence of spawning
and missing a summer of feeding in the sea (Dutil 1986).
Arctic char are iteroparous. That is, they are capable of spawning more than once.
However, annual spawning has not been observed in stocks in the Canadian Arctic.
Spawning is energy-dependent and may occur at intervals of two to four years. Therefore,
some char may spawn only once or twice in their lifetime (Sprules 1952; Johnson 1980).
During nonspawning years, there is evidence that Arctic char may not return to
the "home" stleam to overwinter. Armstrong and Morrow (1980) suggested that
nonspawning anadromous Dolly Varden char (S. malma) entered freshwater more or less
indiscriminately in order to overwinter, and returned to the "parent stream" when ready to
spawn.
Anadromous Arctic char from the Canadian Central Arctic have been tagged on
the spawning grounds and recaptured as nonspawners in winter in other freshwater
systems (Kristofferson unpublished). Johnson (1980) observed more returning
nonspawners to Nauyuk Lake in fall than were counted migrating downstream the
previous spring. Therefore, interchange of anadromous Arctic char between freshwater
systems is known to occur, but the extent of and reasons for this behaviour have yet to be
determined.
Little information is available on the degree of homing of anadromous Arctic char
to natal spawning grounds. Studies by Alm (1951) in Lake Vattern, Sweden, Frost 6
(i963), LeCren and Kipling (1963), and Kipling and LeCren (1984) in Windermere,
England, and McCleave et al. (I977)in Floods Pond, Maine, provide evidence of very strong homing behaviour by landlocked Arctic char spawners. As Johnson (1980) points out, it is unlikely that these nonmigratory populations of Arctic char evolved this homing behaviour after their isolation at the end of the Pleistocene epoch. Most likely, homing was inherited from anadromous ancestors, but proof of homing of anadromous spawners to natal sites has not been established.
Humans and Arctic char
The Arctic char has been a criticallv imoortant element in the subsistence economy of Inuit in Canada's Nunavut T",tiro; (Balikci 1980) and continues to be so today. In areas where an apparent abundance of Arctic char exists, small commercial fisheries have developed that supply local and sometimes export markets (Kristofferson et al. 1984). There is also a growing interest in sport fishing for Arctic char. However, the low fecundity, slow growth rate and infrequent spawning events make the Arctic char particularly wlnerable to overexploitation (Scott and Crossman 1973). Oil and gas exploration and other developments in the Canadian Arctic pose a threat to Arctic char habitat as well.
The Stock
The term "stock" has had many applications in fisheries science. It has been used
to describe a unit of population of lower category than that recognized by taxonomists
(Cushing 1981). From a management perspective, a stock has been characterized by homogeneity of natural production parameters such as growth, recruitment and death rates, and may include a portion of a population or more than one population (Tyler and
Gallucci 1980). An international symposium was held in i980 (Stock Concept
International Symposium [STOCS] convened at Alliston, Ontario, September 29-October
9, 1980) in an attempt to formalize the stock concept. Included in the proceedings Booke
(1981) provided both a general and a precise def,rnition of a fish stock. His general definition is a species group, or population, of fish that maintains and sustains itself in a definable area. This is essentially the "population" or "deme" of Mayr (1963). His precise definition of stock (genotypic) is a population of fish maintaining and sustaining Castle-
Hardy-Weinberg equilibrium. Essentially it describes a stock as a population that has a degree of genetic uniqueness (Larkin lglz),hence a degree of reproductive isolation. The term "stock", as it is used in this study, follows Booke (1981).
Two behavioral characteristics are fundamental to the formation and maintenance of discrete stocks of fish. These include homing of spawners to natal spawning sites and imprinting during early life history stages to the natal site. This results in some degree of reproductive isolation that manifests itself as genotypic-phenotypic differences, which may be adaptive to the local environment (Honall 1981).
Booke (1981) maintains that if genotypic stock characterization is not possible, a phenotypic stock should be recognized. His definition of a phenotypic stock is a group, or population, of fish maintaining characteristics, which are expressed in one or moÍe ways
depending on the type of environment. A phenotypic stock is recognized by any definable
character difference, whether largely genetically controlled or affected in its expression
by the environment. 8
Stocks, then, are the groupings within which genetic adaptation to iocal conditions may develop. They are the proving ground for new genes and gene combinations. Within each stock is a range of individual genetic variation and among all stocks is a range of group variation. Collectively, the extent of the genetic diversity of a species is contained within the aggregate of these local stocks. Human-induced threats to genetic variation generally include harvest and habitat destruction. Therefore, it is important to be able to identify genetically unique local populations or stocks in order to protect them from irreversible reduction due to excessive harvest and loss of habitat (Dizon et al. 1991).
Study Objectives
In this study, I have attempted to demonstrate whether distinct stocks of Arctic char exist within and between several river systems in the Cambridge Bay area, Nunavut
Territory, in Canada's Central Arctic. This includes an examination of some fundamental life history characteristics such as homing to natal spawning grounds and migrations to and from the sea for the purpose of feeding. Toward that end I have compared samples of
spawners both within and among several river systems using morphology, meristic
counts, trace element analysis of otoliths, protein electrophoresis, mitochondrial DNA
analysis and stable isotope analysis. The first hypothesis to be tested is:
Ho: Arctic char from the various locations sampled in the study area comprise a
panmictic population.
Ha: Arctic char from the various locations sampled in the study area are
comprised of discrete populations. 9
Char that are not spawning in a given year may overwinter in a river system other than their natal river system. Therefore, I have also gathered these data from samples of nonspawners from these systems taken during fall upstream migrations in order to determine whether these migrations are comprised of char from more than one stock.
Therefore, the second hypothesis to be tested is:
Ho: The upstream migration of Arctic char in river systems within the study area
is comprised of individuals from a discrete homogeneous population.
Ha: The upstream migration of Arctic char in river systems within the study area
is comprised of a mixture of individuals from more than one discrete
population. '
In the Canadian Arctic. the entire Arctic char resource is encompassed within two
settled land claim areas. In the west is the Inuvialuit Settlement Region, and in the central
and eastern areas, the newly created territory of Nunavut, which includes the study area.
The Federal Government has entered into legislated comanagement of fish resources with
both of these groups. Comanagement provides fishers with an opportunity to play a
participatory role in the management of this important resource as well as to contribute
their traditional knowledge to the management process. This traditional knowledge was
vital to this study, in particular in the identification of spawning areas. There is a pressing
need to develop a more effective management approach to the utilization of the Arctic
char resource in orderto preserve the genetic diversity ofthe species. Therefore, an
additional objective of this study is to outline how this new management relationship can
provide a more effective means of managing this important resource in light of the results
of this study. 10
MATERIALS AND METHODS
The Study Area
Geography and Geolog.y
The study area is centred around the community of Cambridge Bay (69. 07' N, i05' 03' W) on the south shore of Victoria Island. (Fig.2). Victoria Island is the second largest island in the Canadian Arctic Archipelago and is part of the Arctic Lowiands physiographic region. The southeastern portion, including the study area, is part of the
Victoria Lowland (Bostock 1970,1972). The surface topography of the study area is relatively flat with the exception of eskers, moraines and drumlins. It is dotted with many small lakes and seasonal streams and also some lakes of considerable size (Johnson
1962). The surface is primarily covered by unconsolidated glacial drift. Vegetation is predominantly sedges, grasses and mosses with lichens appearing on rock outcrops
(Peterson et al. 1981). The underlying geology consists of Paleozoic limestones, sandstones, dolomites and shales (Thorsteinsson and Tozer 1962,1970; Fyles 1963;
Douglas 197 I, 1973; Campbell 198i).
Most of Victoria Island, including the study area, was covered by the Laurentide
Ice Sheet. The glaciers are believed to have melted between 8 500 and 12 500 years ago, based on radiocarbon dates of marine bivalve shells found at elevations above 80 m asl
(Fyles 1963; Prest et al.1972; Prest 1973). Much of the southeast comer of the island including almost all of the study area was inundated by sea water following glacial retreat
(Wilson et al. i958). Over time, the land rose, apparently at a uniform rate, based on the il
Figure 2.Map of the study area showing locations of river systems sampled. t¿ spacing between strand lines (Johnson 1962). The rate of elevation has been estimated at between 1.96 m and i.16 m per 100 years. The explorer Collinson surveyed Cambridge
Bay Harbow in 1853 and charted a reef 61 cm below sea level in an unambiguous location. Washburn (1947, cited in Johnson 1962) observed that the shoal was 33 cm above sea level at the highest high tide in 1947. This change in elevation of the shoal suggests that the area near Cambridge Bay has risen from the sea within the last 1 300 years (Johnson 1962).
The Communitv of Cambridee Bay
The Inuit name for the community of Cambridge Bay is "Ikaluktutiak" which means fair fishing place (Abrahamson T964).Inuit were known to congregate here in autumn to fish for the abundant Arctic char that made their way up Freshwater Creek to overwinter in the Greiner Lake system. The first permanent contact with people of
European origin from Southern Canada began in I92l when the Hudson's Bay Company established a trading post there. Over the years various missions and a Royal Canadian
Mounted Police post were established as well, but Inuit continued to live off the land. In
1946-47 United States and Canadian military interests constructed a Long-Range
Navigation (L.O.R.A.N.) beacon. This offered some wage employment to local Inuit who then began living in the settlement. More job opportunities occurred as a result of the construction of a Distant Early'Warning (DEVD site in 1955-56. This was followed in later years by the location of various government agencies in the community
(Abrahams on 1964). Today the community consists of over 1 100 inhabitants, most of whom are Inuit (NWT Data Book i991) and commercial f,rshing plays an important role
in the local economy. la IJ
The Fisherv
Fishing for food was and still is a very important activity for the Inuit of
Cambridge Bay. Commercial fishing by gillnet began in 1960 when approximately 2000 kg of Arctic char and some lake char (Salvelinus namaycush) were taken from nearby
Freshwater Creek. However, this fishery was in direct competition with the food fishery and, after a few years, it was clear that the Arctic char stock was suffering from overexploitation. The commercial fishery was relocated to Wellington Bay, at the mouth
of the Ferguson River in 1962 (Abrahams on 1964; Barlishen and Webber 1 973). The
Ferguson River is now known as the Ekalluk River. Ferguson Lake, upstream on the
Ekalluk River, was also fished in both suÍrmer and winter. As the fishery developed, other sites were established. These included the Halovik (Thirty Mile) River, the
Paliryuak (Suney) River, the Lauchlan River (Byron Bay), all of which flow into
Wellington Bay (Fig. 2), and the Jayco River, emptying into Albert Edward Bay. Two rivers on the mainland, the Ellice and the Perry, were also fished (Barlishen and'Webber
1973). Arctic char was and still is the target species of the fishery.
Fishing with gillnets (139 mm mesh, stretched measure) takes place at the mouths of the various rivers. The catch is dressed on site and flown by float-equipped aircraft to the processing facility where it is cleaned and fast-frozen and then delivered to market
(Kristofferson and Carder 1980; Kristofferson et al. 1984). The first processing facility was located at the mouth of the Ekalluk River but was subsequentiy moved to Cambridge
Bay in 1972 (Barlishen and Webber I973).In the early years, fishing took place both in
spring and in fall. This was done because the processing facility had a limited capacity
and the allowable harvest was too much to process at one time. Today, most commercial 14 fishing for Arctic char in the Cambridge Bay area targets the fall upstream run, all of which can be processed in a larger facility.
A traditional Inuit method of harvesting Arctic char employed a stone weir or
"saputit" installed across a river to trap upstream migrants which were then speared in the shallow enclosures (Balikci 1980). The Department of Fisheries and Oceans used a modern version of the weir to enumerate the upstream migration of Arctic char for population studies. This weir, made of vertically arranged conduit pipe, was also evaluated as a commercial harvesting gear (Kristofferson et al. 1986). Although gillnets are still the mainstay fishing gear, conduit-pipe weirs are used at two locations.
Sampling Locations and Sample Collection
I had very little information about the location of the spawning grounds of Arctic char in the study aÍea at the outset of this study. During discussions with Inuit fishers of
Cambridge Bay, I explained the need to sample spawners in order to gain a better understanding of their biology, which in turn, would contribute to better management of the resource for present and future generations. After some discussion, they agreed to
assist me. Using their traditional ecological knowledge of the area, they identified the
spawning locations on a map, and in some cases, led me directly to them. I was therefore
able to collect myself or obtain from others samples of spawners at seventeen different
sites in nine different river systems on Victoria Island. Most of the spawners were
captured by gillnet (139 mm mesh, stretched measure, 47-50 m long and2-3 m deep) in
upstream lakes between mid-August and early September, because most Arctic char do
not go to sea the summer before spawning. They were easily recognized as spawners by l5 extemal examination based on their bright orange-red spawning colouration. Samples from four locations were captured through the ice in December. Nonspawners were collected in the mouths of rivers as they made their way in from the sea dwing late
August to early September. Most were taken with gillnets (i39 mm mesh, stretched measure) by myself and in some cases by the commercial gillnet fishery. Some were taken in a weir used by the commercial fishery. Samples were also taken in a seine net and counting weir at Freshwater Creek by Department of Fisheries and Oceans (DFO) staff. The latter captured all size ranges present in the run. Details of the collection of spawners is provided in Table 1 and of nonspawners in Table 2.The coordinates for river systems sampled identify the river mouth. Following is a brief description of each of the river systems and the sampling activity that took place there:
EKALLUK RIVER rcg' 23' N. 106' 18' WI
The Ekalluk River drains an area of approximately 5 835 km' (Fig. 3). Its headwaters begin about 200 km from the sea, at an elevation of 185 m above sea level. It begins by draining a myriad of small tundra potholes in a southward flow, consolidating into a main branch about 185 km from its outlet. At this point it widens to almost 0.5 km, forming a narrow lake that stretches for about 12 km in a southeasterly direction (69" 57'
N, 105o 07' VD. Local residents report that Arctic char spawners have been taken in this section of the river (D. Hamilton pers. comm.). The river narrows once again, flowing for about 10 km in an easterly direction into a large unnamed lake (69" 46'N, 104o 30' 16
Table 1. A summary of the sampling details for the collection of Arctic char spawners.
LOCATION DATE GEAR N
(Ekalluk River System) Lady Pelly 69o Lake 22,N, l05o 03' W Dec. 1987 Gillnet 51 Wishbone Lake 69o 34,N, 104o 10, V/ Aug. 16 1994 Gillnet 60 Ferguson Lake 69" 24,N, 106o i3' V/ Sept.3 1996 Gillnet +JA' Palir¡rak River 69" 40,N, 106o 40, W Dec. 1987 Gillnet 5
Halovik River 69" 16'N, 108o 00' W Dec. 1987 Gillnet 30* 690 I7',N, 10go 03, v/ 4ug.241993 Gillnet 20 69" 14'N, 10go 20,w Aug.22-27 1993 Gillnet J¿
Lauchlan River 69" 04'N. 109. 14, W Dec. 1987 {¿lT Gillnet -'l 69" 03' N, tol" 06''w 4u9.281993 Gillnet 2
Char Lake 69" 37'N, 103" 35' W Aug. 18-23 1991 Gillnet 36 69" 36',N, 1030 34' W Aug. 19 1991 Gillnet 10
Fish Trap Lake 69" 39,N, 103o 34,W Aug. 18-19 i991 Gillnet 11
Kitiga Lake 69" 14'N, 105o 37,W Sept. 1994 Gillnet ¿J
AndersonBay L Sept.1993 Gillnet 31 iJ'.'ä1k:läT,?ffi"* Aug.17 1994 Gillnet 28
(Freshwater Creek System) Mount Pelly L. 69" 12'N, 104" 44, W Aug.30 1991 Gillnet I Mount Pelly L. 69" 12'N, 104" 44, W Aug.25-28 1992 Gillnet 44 Mount Pelly 69o L. 12'N, 104" 43, W Aug25-26 1993 Gillnet 11
* only 13 whole specimens. Tissue samples from remaining 17 specimens. t only 4 whole specimens. Tissue samples from remaining 30 spècimens. t7
Table 2. A summary of the sampling details for the collection of nonspawning Arctic char.
LOCATION DATE GEAR
Ekalluk River 69" 23',N, 1060 19, w Sept. 9 1988 Gillnet 51 Ekalluk River 69" 23'.N, 106o 1g' V/ Aug.16-221990 Gillnet 50* Ekalluk River 69" 23',N, 106" ig' W Aug.24-25 1991 Gillnet 50 Ekalluk River 69" 23',N, 106o 1g' W Ãug. 27 -28 1992 Gillnet 51 Ekalluk River 69" 23',N, 1060 1g'W Aug.28 1993 Gillnet 50 Ekalluk River 69" 23',N, 1060 1g' V/ Aug.27 1994 Gillnet 49
Paliryuak River 69" 27',N, 1060 40' W Iul.17-19 1992 Gillnet 52*
Halovik River 690 09',N, 1070 06'W Aug.2I-22 1992 Gillnet 52
Lauchlan River 68" 57',N, 10go 32'W Aug.2l 1992 Gillnet 57 Lauchlan River 68" 57',N, 10go 32'W Iuly 17 1996 Gillnet 50+
Freshwater Ck. 690 08'N, 1040 59, W Aug. 20 - Sept. 10 1988 Weir 125 Freshwater Ck. 69'08',N, 104o 5g',W Aug. 14 - Sept. 121991 Weir 87 Freshwater Ck. 690 08',N, 1040 5g'w Aug.23 -Sept.71994 Weir 100
Ellice River 680 03'N, 104" 00'w Aug.24-27 1990 Gillnet 50*
Jayco River 69" 44',N, 103" i6' W Aug. 31 - Sept. 10 1990 Weir 49'+
* Samples taken from commercial fishery t8
FERGUSON LAKE
GILLNETS ujJ-\
r la WY3 -pa. t l-"år.¡ A& ge lå rq Þl s\Þ d( d ¡+)\
FAY j "À\t4 'qft tt+{ -"t-#x 1 -i--\a" I \ \\ ,-\" \ \ t' +ø q$
Figwe 3. Map of the Ekalluk River drainage basin showing sampling locations of Arctic char spawners at Lady Pelly Lake in 7987, V/ishbone Lake in 1994 and Ferguson Lake in 1996. Upstream migrants were sampled at the mouth of the Ekalluk River (1988, 1990,1991,1992,1993,1994) where it empties into Wellington Bay. 19
W). The upper reaches of this lake are also reported to be an Arctic char spawning ground. Downstream of this lake, the river continues to flow in a southeasterly direction for another 20 km where it meets a small irregular-shaped lake on its east bank (69" 34'
N, 104o 10' W). I call this unnamed lake Wishbone Lake due to its shape. Wishbone Lake is one of three locations on the Ekalluk River system where Arctic char spawners \ /ere captured for this study. The sample from Wishbone Lake was taken on August 16,1994 from four gillnets set the previous day at the location shown in Fig. 3. The gillnets were set on the surface perpendicular to shore with one end fastened to the shore. At least 11 spawners were captured in each net with the most northerly net taking 26 for a total of 60 fish. This capture site is 98 km upstream from the sea.
Downstream of Wishbone Lake, the river continues in a southwesterly direction for about 11 km and drains into the east end of Ferguson Lake. Ferguson Lake is the largest lake on Victoria Island at740 km2 in surface area. It is 75 km iong in an east-west
direction and is 15 km wide at its widest point. Its elevation above sea level is about 1 1 m. Approximately 30 km west of the inlet to Ferguson Lake, on its south shore, is an esker elevation known as Mount Lady Pelly. A relatively large lake,7 km long and 4 km wide, is situated on the southwest side of this esker (69" 22'N,105' 03' W). This lake drains into Ferguson Lake by a very narrow stream over a length of about 2.5 km. This stream is very shailow and is likely passable to Arctic char oniy during the spring high water period. I call this unnamed lake Lady Pelly Lake and it is the second location on the
Ekalluk River system where I obtained Arctic char spawners. This sample of 51 Arctic 20 char was taken from this lake in December 1987 by gillnet at an unspecified location.
This lake is 54 km upstream from the sea.
Ferguson Lake narrows considerably near its outlet at its west end. I obtained the third sample of Arctic char spawners from Ferguson Lake on September 3, 1996 at a location about 0.5 km from the Lake's outlet (69" 24'N, 106o 13' VD. This sample of 43
Arctic char was taken from two gillnets set on the north shore on September 2. Each net was fastened to shore and set perpendicular to the shoreline. At this location, the lake is about 0.5 km wide. The Ekalluk River then drains Fersuson Lake into the Arctic Ocean over a short fast run of about 4 km. This capture location is about 4.5 km uostream from the sea.
I obtained samples of nonspawning Arctic char from the upstream run in freshwater at a location about 0.5 km from the mouth of the Ekalluk River (69" 23'N-
106' 18' W) on September 9, 1988. Samples were taken from the commercial gillnet fishery from August T6-22,1990. Samples were taken on August 24-25,1991, August
27-28,1992, AugustZ8,1993 and Augustz7,1994 at the same location by myself or by other DFO staff using gillnets.
PALIRYUAK (SURREY) RIVER (69" 27',N, 106o 40' SD
This river drains an area of 14 913 km2 into Wellington Bay from the northwest
(Fig. ). Although it drains a series of relatively large lakes, including Washburn Lake with a surface areaof 292 km2, and has a substantial flow even in late surnmer, it does not appear to be used as an over\¡/intering system for anadromous Arctic char. There is little 2l
OMMERCIAL
-l
*l v 4;.If r"r ,ft\|f' $k;(,/\,
@È1Þ l\ I þ e¡S. ¡¡t\ \ ¡ '¿P _P\\\ \ t { ln "}< :^-t- -.S*",\ Ï'JlVJ¿<*-l r"n\, 4*S+V¿
Figure 4.Map of the Palir¡rak River drainage basin showing sampling locations of Arctic char spawners in 1987 and the 7992 commercial giilnet fishery. 22 evidence of old camp sites near the mouth and local knowledge (Abrahamson 1964) and an unsuccessful attempt to enumerate an upstream mn here by DFO staff in 1983 has led to this conclusion. However, the site is used for commercial fishing, particularly in the spring (Kristofferson and Carder 1980). Gillnets are set mostly in brackish water near the mouth of the river (69' 27'N,106' 40' W) and likely intercept itinerant char as they move along the coast feeding in summer. I obtained a sample of nonspawning Arctic char from this commercial fishery on July 17 -I9, 1992 to compare with samples of nonspawners from other locations. A small number Q.{:5) of spawners was obtained opportunistically from an upstream lake (69' 40'N, 106o 40' \Ð in December 1987.
HALOVIK (THIRTY MILE) RIVER (69' 09',N, 107o 06', W) .Wellington The Halovik River flows into Bay from the west-northwest (Fig. 5) and drains an area of 2 450 km2. It has its headwaters approximately 110 km upstream at an elevation of about 185 m above sea level. Approximately 42 km upstream from the mouth it drains an irregular-shaped lake that is 7 km at its longest and 6 km at its widest point. I captured 20 Arctic char spawners in two gillnets set off a point (69' 17'N, 108"
03' UD in the middle of this lake on August 24,1993. During the same sampling period, I obtained an additional 32 spawners on August 22,25,26 and27 afixther 7 km upstream from this lake. These spawners were captured in a series of narrow bays (69" 14'N, 108"
20' W) that formed the outlet of a larger lake to the west. This lake is about 20 km long.
In total, 52 spawners were captured from these locations. Upstream, for an additional 30 km, the Halovik River drains a myriad of small tundra potholes at its higher elevation. A ¿J
Figure 5. Map of the Halovik River drainage basin showing sampling locations of Arctic char spawners at Halovik Lake 1987 and 1993, the weir site, and the sampling location of the 1992 upstream migration. 24 sample of 30 Arctic char, reported to be spawners, was taken opportunisticaliy at 69" 76
N, i08" 00' W, in December 1987. Of these, only l3 were whole specimens which were incorporated into my morphologicai analysis. Only the tails of the remaining 17 chat were kept so tissue samples from these fish were used in the electrophoretic analysis.
The commercial fishery is located at the mouth of the Halovik River (69' 09'N,
107" 06' W). In the past, gillnets were used during the spring and some were set in brackish water off the mouth of the river. Today, a weir is used about 1 km upstream in freshwater and the catch is taken in fall from the upstream run. I captured 52 nonspawning Arctic char with gillnets set in freshwater near the mouth of this river on
August 2I,22,1992 as the upstream tun returned from the sea.
LAUCHLAN RIVER (BYRON BAY) (68" 57'N, 108o 32' V/)
The Lauchlan River drains an area of 7 935 km2 and has its headwaters at an
elevation of 235 m above sea level, approximately 190 km northeast of its outlet into
Dease Strait (Fig. 6). A sample of 34 Arctic char, reported to be spawners, was obtained
opportunistically in December 1987 from a lake 35 km upstream from the mouth at 69o
04'N, I09" 14'W. Of these, only 4 whole specimens were kept along with the tails from
the remaining 30 fish. Therefore, only tissue samples were available from the latter 30
specimens. Two spawners were obtained from a lake (69" 03'N, i09' 06' W)
approximately 30 km upstream of the mouth on August 28,1993.I captured 57
nonspawners by gillnet as the upstream run entered the mouth of the river on August 21, 25
Figure 6. Map of the Lauchlan River drainage basin showing sampling location of Arctic char spawners in 1987, and the sampling location at the 1992 andthe 1996 commercial gillnet fi sheries. ¿o
7992 and a sample of 50 nonspa\ilners was obtained from the commercial gillnet fishery which was located near the mouth of the river in Julv i7. 1996.
JAYCO RIVER (69" 42'N, 103o 17'UD
The mouth of this river is located 100 km northeast of Cambridge Bay and empties into Albert Edward Bay (Fig. 7). Its headwaters lie about 120 km to the northwest of its outlet at an elevation of 140 m above sea level and it drains an area of 3
T3 krrt. There is a large lake, called Jayco Lake, 5 km upstream from the mouth of the river (69o 48'N, 103" 10' W). This lake is 21 km at its longest stretch and 11 .km at its widest point. Anadromous Arctic char migrate up this short stretch of the Jayco River into this lake in autumn to overwinter. The commercial fishery is located at the outlet of this lake at 69" 44' N, 1 03 " I 6' W and a weir is used for the harvest.
Although I did not obtain spawners from the Jayco River system, I did capture spawners from an adjacent system which empties into Albert Edward Bay at 69o 42' N, l03o 27' W (Fig. 8). This system drains an area of about I 632'Krrrr. Local residents believe that Arctic char from the Jayco River system will overwinter in this system during low water years when the lower Jayco River becomes very shallow. The first lake on this system that I sampled, known locally as Fish Trap Lake, is a small lake about 0.5 km long and I km wide located 10 km upstream from the sea. I captured a total of 11
Arctic char spawners from this lake from two overnight sets lifted on August 18 and 19,
1991. The two gillnets were set perpendicular to shore on either side of the inlet at 69" 27
I \\'¡.) t'{I s'X / \\ /, \ç\T; &ÆÅ ( å Y\ ífl í'{\\r d q, /-:*_ !l'f\Y , ß,ra( \l {\?s
$ee,Þ {}Tl+'\R\ 5'* 1l \ ;v\ ( ilh\\q-jLss
Figrne 7.Map of the Jayco River drainage basin showing sampling location of the i990 upstream migration of Arctic char at the weir. 28
Figwe 8. Map of the drainage basin showing sampling locations of Arctic char spawners at Char and Fish Trap iakes in i991. 29
39'N, I03" 34' V/. I also captured spa\^/ners from the next lake 1 km upstream on this system. This lake, located at (69' 36'N, 103o 35' W), is known locally as Char Lake. One net was set perpendicular to shore on the west side of the lake at (69" 37'N, i03" 35' UD just south of Arctic Outpost Carop and the other was set perpendicular to the east shore at
(69" 36'N, 103o 34' VD. The nets were set overnight and lifted the following day. A totai of 46 spawners were captured on August 18, 19 and23,1991 from this lake.
ELLICE RIVER (68'03',N, 1o4o 00'VD
The Ellice River is located on the mainland south of Victoria Island (Fig. 9), and drains an area of about 20 627 km2. Its headwaters besin over 250 km to the south of its outlet to the sea. There is a fork in the river about 28 km upstream of its mouth and a set of rapids on the main stem is likely impassable to upstream migrating Arctic char. The west channel follows azígzag pattern for about 40 km where it serves as the outlet of
Brichta Lake (67" 45'N, 104 52' V/). It is not known whether anadromous Arctic char
overwinter in this lake. The lower reaches of the Ellice River are influenced bv tidal
surges. A water sample taken at a location 5 km from the mouth contained brackish
water. The commercial fishery takes place in the mouth of the river and a short distance
upstream. I obtained a sample of 50 nonspawning Arctic char from this commercial
gillnet fishery during the period of August 24-27, T990. 30
Figure 9. Map of the Ellice River drainage basin showing sampling location of Arctic char at the 1990 commerciai gillnet fishery. 31
KITIGA LAKE (69" 14'N, 105o 37' \Ð
This lake,located 2zkmnortheast of Cambridge Bay (Fig. 10), was set aside by local Inuit residents for subsistence fishing only. It drains an area of about 445 km2. This relatively large lake is divided into two basins that are connected by a narrow channel.
Situated at an elevation of 40 m above sea level, it drains to the west into Wellington Bay through a narrow (3-4 m wide) outlet over a distance of 15 km. I obtained a sample of spawning Arctic char from this lake from a local resident of Cambridge Bay who used gillnets set in the general vicinity of 69" 14'N, 105" 37' W in September 1994.
FRESHWATER CREEK (69" 07'N. 105' 01' W)
Freshwater Creek is located 2 km east of the community of Cambridge Bay (Fig.
1i). Although it was the site of the first commercial f,rshery in this area, today fishing at this location is for food and recreation only. The drainage basin covers an area ofabout I
532l 60 m above sea level. Residents of Cambridge Bay concluded that the anadromous Arctic char stock in this system was depleted and asked DFO to help with its rehabilitation. A restricted angling harvest and voluntarily reduction in the harvest of the food fishery was put into effect to reduce fishing pressure in this area. In addition, DFO staff enumerated upstream migrations of anadromous Arctic char in this system on four occasions using a weir. The 32 Figure 10. Map of the Kitiga Lake drainage basin showing sampling location of Arctic char spawners in 1994. JJ L¡ è q ,fuh% eþ rgss "r/' Figure 11. Ivlap of the Freshwater Creek drainage basin showing sampling locations of Arctic char spawners at Mount Pelly Lake 1992 and i993, and the weir site where the upstream migration was sampled in 1988, 1991 and 1994. wefu was located at 69o 08' N, 104o 58' W, near the outlet of Greiner Lake (Fig. 1 1). I was able to obtain samples of nonspawning anadromous Arctic char from the weir during the period August 20- September 10, 1988. I also obtained samples taken in the weir over the period of August l4-September 12,1991 and August 23-September 7,1994.I captured spawners by gillnet from a small lake (69' 12'N, 104o 44'W) 2 km upstream of Greiner Lake (Fig. 11) over a three-year period (1991-93). I call this small lake Mount Pelly Lake because it is located at the northwest slope of Mount Pelly, the highest geographic feature (203 m) in the area. The 1991 sample of one char was taken in early September.The 1992 sample was taken on August 25-28 and the i993 sample was taken on August 25 and 26. Nets were set perpendicular to shore and left in overnight. ANDERSON BAY LAKE (68O 56'N. 104" 14' 'WJ This unnamed lake is located 40 km southeast of Cambridge Bay on the east side of Anderson Bay (Fig. 12). I call this lake Anderson Bay Lake and I was able to obtain a sample of Arctic char spawners from this lake taken by a local resident using gillnets in September 1993. The exact location of the set is unknown. I captured a sample of 28 spawners in two gillnets on August 17,lg94at 68o 54'N, i04' i6' W. The take is 7 km long and 4 km wide at its widest point. Its drainage area, about 189 km2, does not appear to extend much beyond 18 km of its shoreline. It drains into the sea through a very short (1 km) and very shallow outlet. It appears that Arctic char could be prevented from entering this lake from the sea during low water years. 35 Figure 12. Map of the Anderson Bay Lake drainage basin showing sampling location of Arctic char spawners at Anderson Bay Lake in 1994. The 1993 sample location is not shown. 36 Biological Variables Examined Five biological variables were measured on each whole specimen. They are listed below with their codes and include: Weight (WT): measured in grams to the nearest gram. Sex (SEX): determined by gross examination of the gonads (Males : 1, Females :2). Maturit), (MAT): coded by developmental stage of gonads as follows: Maturity State Female Code Male Code Immature (Virgin) 6 Mature (Spawner) l Ripe and Running 8 Spent 9 Post Spawner (Prev. Year) 10 Unknown (Virgin) 0 UnknownQ'{on-virgin) 1i Gonad Weight (GWT): measured in grams to the nearest gram. Ase (AGE): estimated by examination of a cross section of the sagittal otolith under magnification (X 4) and counting the annuli according to Nordeng (1961). Morphometric Measurements Twenty-one morphometric measurements were taken on whole specimens following Reist et al. (1995). All measurements were taken on the left side of the fish 31 except if the fish was damaged and the right side had to be used (infrequent). Gill raker and gill arch measurements were taken from the first right gill arch. The measurements are described below and illustrated in Fis. 13: a) measurements taken parallel to the iong axis of the body: Standard length (STL): measured from the tip of the snout to the caudal flexure, the latter being the base of the caudal fin rays indicated by a crease when the tail is flexed. Fork leneth (FRL): tip of the snout to the fork of the tail, to the nearest 1.0 mm. Preorbital length (POL): tip of snout posterior to the anterior fleshy margin of the orbit. Orbital leneth (OOL): anterior fleshy margin of the orbit to posterior fleshy margin of the orbit. Postorbital lensth (PSL): posterior fleshy margin of the orbit to the end projection of the bony operculum. Trunk length (TTL): posterior end of bony operculum to the origin of the dorsal fin. Dorsal length (DOL): origin of the dorsal fin posterior to the end of the fin ray base. Lumbar leneth (LUL): end of dorsal fin to the origin of the anal fin. Anal leneth (ANL): origin of anal fin posterior to the end of the fin ray base. Caudal peduncle length (CPL): end of the anal fin posterior to the caudal flexure. b) measurements taken parallel to the dorsoventral body axis: Head depth (HDD): vertical depth through the centre of the pupil perpendicular to the long axis of the body. :tJi f ). gl o-7. i.;i :- õr' t-P. ig*-' +;;úñ'o q ì lr.. ". UGR GRI. Glll Arch Figure 13. The morphological variables examined in this study. A description of each measurement and acronym is provided in the text. (by permission of Dr. J.D. Reist) 39 Body depth (BDD): vertical depth from dorsal origin to ventral surface of the body, perpendicular to the long axis of the body. Caudal peduncle depth (CPD): the shortest vertical depth from dorsal to ventral swface of the caudal peduncle. c) measurements parallel to the lateral body axis: Interorbital width (IOW): measured on the dorsal surface of the head; it is the distance between the orbits. d) measurements following the axis of the body part: Maxillary leneth (MXL): anterior most to posterior most point of the maxillary. Maxillar)'width (MXW): widest depth of the maxillary (bony structwe only) perpendicular to the length of the maxillary. Pectoral fin length (PCL): anterior most part of the first fin ray to the end of the fin. Pelvic fin length (PVL): anterior most part of the first fin ray to the end of the fin. Adipose fin length (ADL): measured from the point where the skin and scales meet at the anterior end of the fin posterior to the end of the fin. Middle gill raker length (GRL): on the first right side gill arch, the base of the middle gill raker to its tip. Lower gill raker arch leneth (LAL): on the lower arch of the f,rrst right side gill arch, base of the middle gill raker to the base of the last gill raker. 40 Meristic Counts Eight meristic counts were made on whole specimens following Reist et al. (1995). They are described as follows: Dorsal fin rav count (DRC): first unbranched ray forming the leading edge of the fin back to the last ray; rays arising from a com.mon base are counted as one. Anal fin ray count (ARC): first unbranched ray forming the leading edge of the fin back to the last ray; rays arising from a cornmon base are counted as one. Pectoral fin ray count (PCR): ray forming the leading edge of the fin back to the final ray. Pelvic fin ray count (VRC): ray forming the leading edge of the fin back to the final ray. Branchiosteqal ray count (BRC): total number of branchiostegal rays. Upper gill raker count (UGR): on the right first gill arch, topmost to and including the one immediately above the middle gill raker. Every raker is counted including bony rudiments that can be felt with a probe. Lower qill raker count (LGR): on the right first gill arch, middle giil raker to the bottom most raker including bony rudiments that can be felt with a probe. Pyloric caeca count (PYL): total number of pyloric caeca. Genetic Analyses Electrophoresis All specimens of Arctic char collected were frozen less than one day after capture and shipped to the Freshwater Institute in Winnipeg by air freight. They were then stored at -35o C until examined. The hsh were thawed to take morphological measurements and 4l during this process, tissue samples were extracted and immediately refrozen until enzyme extraction took place. Extracts from liver and white muscle were prepared by macerating one gram of tissue in a ratio of 1:3 with 0.25 M sucrose (Reist 1989), with coenzyme NADP used with the white muscle. Samples were spun at 14 000 rpm for 10 minutes at 4o C to remove cell debris. The supernatants were withdrawn and stored at-20" C until used. The micro-starch gel electrophoresis technique of Tsuyuki et al. (1966) was carried out on the following six enzyme systems: Phosphoglucomutase (PGM) Enzyme Commission (E.C.) No. 2.7.5.i Malic Enzyme (ME) E.C. 1.1.1.40 Esterase (EST) E.C. 3.1.1.1 Isocitrate dehydrogenase (IDH) E.C. 1 .1.1.42 Superoxide dismutase (SOD) E.C. 1.15.1.1 Phosphoglucose isomerase (PGI) E.C. 5.3.1.9 Details are provided in Table 3. Samples from fìve spawning aggregations and nine nonspawning aggregations were examined. Mitochondrial DNA (mtDNA) Total genomic DNA extraction was carried out on white muscle tissue from samples taken from the Ekalluk, Halovik and Ellice rivers, and Anderson Bay. The extraction method followed Sambrook et al. (1989) with some modification (Maiers et al. 1998). The tissue was homogenized and digested with proteinase K, followed by phenol- chloroform extraction and DNA precipitation. Amplification of the mtDNA control /l '', Table 3. Summary of starch gel electrophoresis protocols used on Arctic char samples. Enzvme Tissue pH Buffer Voltaee Duration GPI-3 white muscle 8.0 0.002 M citric acid 160 v 2.0 h ME white muscle 6.t 0.002 M citric acid 210 v 2.s h EST liver 6.1 0.002 M citric acid 210 v 2.5h IDH liver 6.\ 0.002 M citric acid 270 v 2.sh SOD liver 6.1 0.002 M citric acid 200 v 2.0 h PGM white muscle 6.1 0.002 M citric acid 210 v 2.sh Enzvme DH Buffer Additives I)uration GPI-3 8.0 0.1 M TRIS (HCl) NBT,PMS, MgCl2 . 4}JzO l-zh fructose-6-phosphate glucose-6-phosphate dehyd. ME 8.0 0.15 MBicine 2.0 M malic acid, MgC12. 1.5 h NADP, NBT, PMS EST 6.5 0.05 M phosphate a naphtþl acetate. t h Acetone, Fast Blue RR IDH 8.5 0.15 M Bicine sodium isocitrate, 0.5-1.5 h MBCIz '4H2O,NADP, NBT,PMS SOD 9.0 0.15 M Diethanolamine NBT. PMS 2.0 h (expose to bright light) 0.15 MgClz . 4I{2 0.5 h PGM 8.0 M Tricine . O, glucose-1-phosphæe glucose-6 -phosphate dehyd. NADP, NBT, PMS NADP : Nicotinamide Adenine Dinucleotide Phosphate NBT : Nitoblue Tehazolium chloride monohydrate PMS: Phenazine Methosulfate 43 region was carried out using HN20 and LN20 primers using the polymerase chain reaction (PCR) as described by Brown Gladden et al. (1995). The amplified mtDNA was then purified using a PCR purification kit (Quiagin Inc.). The mtDNA samples were then sent to the National Research Council, University of Saskatchewan, Saskatoon, SK, and processed using an Applied Biosystems Prism 377 attomated sequencer and the d Rhodamine dye terminator sequencing chemistry. The resulting sequences were aligned and examined for sequence variation using the MacVector program (IBI)(Brown Gladden et al. 1995). Stable Isotope Analysis Stable isotope analysis was carried out on white muscle samples of Arctic char from four nonspawning aggregations (Ekalluk, Jayco, Ellice and Halovik rivers) and one sample of spawners (Char lake) in order to examine food sources and trophic levels utilized by these char. The stable isotopes of carbon (t3C) and nitrogen (15N) were examined from a single aliquot of about 15 mg of dried white muscle. The stable isotope of sulfur ('oS ) required approximately 1 g of dry tissue. The samples for sulfur analysis were converted to sulfate by nitric acid digestion, nitrate fusion and precipitation with barium chloride, followed by thermal decomposition to sulfur dioxide. Nitrogen and carbon samples were combusted to nitrogen gas and carbon dioxide by a modified Dumas method, and then cryogenically separated and trapped. The preparation is described in detail by Hesslein et al. (1989). The isotopic determinations were performed on a dual-inlet ratio mass spectrometer (VG Micromass 6028). The carbon was standardized to PDB and the 44 nitrogen \ilas standardized against air. Standards used for sulfir were traceable to Canyon Diablo Troilite (CDT). Micro-PIXE Analysis of Otolith Strontium Concentrations The proton microbeam (Proton Induced X-ray Emission or PIXE) (Fig. la) functions by exciting a sample with a beam of protons, usually accelerated to an energy equivalent to 2 to 3 MeV but sometimes up to 5 MeV. Interaction with atoms on selected areas of the surface of samples causes the emission of X-rays with wave iengths characteristic of each element present and allows for the identification of elements present in the sample. The X-ray intensity allows for the quantification of each element present. The beam can be focussed down to a minimum diameter of about lprm for microanalysis. Detection limits from excited areas down to 5-10 pm are in the ppm range. This technique can detect Sr at very low levels (0.5-1.0 ppm) compared with other element assay techniques (Campana et al- 1997). Sagittal otoiiths of the Arctic char samples were removed in the laboratory when the specimens were thawed for processing. The otoliths were cleaned and placed in envelopes for dry storage. The proton microprobe methodology followed Halden et al. (1995). In preparation for the proton microprobe analysis, the otoliths were mounted in epoxy resin in a lucite-disc probe mount (25.4mm diameter). The surface of the otolith and disc was then ground to expose a dorso-ventral cross section through the nucleus of the otolith. The ground surface was then polished and carbon coated. Just prior to carbon coating, an optical image of each otolith cross section was recorded in glancing reflected Scqnning Proton M¡croproþe (SPM) somple lens operture syslem bendlng mognet lon Source ond occelerotor obfecl oþeilure @ /o"""'o' olollth Line Scon X-roy spectrum (ìÞ 000 9r ppm õ00 tP0 J 4l¡e : 100 r û¡0 o .E È 300 t la0 fr to' xr n o.Ìræ 7Ð É, Ito' t00 395 0 ld '10 o 600 to00 túoQ ¡000 Dlslence from nudor¡¡ ln rjcfons Energy (KeV) Figure 14. Diagram of Scanning Proton Microprobe used in micro-PIXE analysis- (by permission of Mr. J. Babaluk) 46 light. This image provided good resolution of the otolith nucleus and arurual growth zones. A minimum thickness of 60 ¡rm of otolith material was retained to stop the proton beam from exiting the mounting medium. One-dimensional line scans were obtained by rastering the proton beam. X-ray intensities and corresponding X-Y coordinates were recorded to computer disc in list mode. The X-ray maps comprised 256 x 256 pixels covering an area of 400 x 400 pm. Line scans were created by focussing the proton beam at the nucleus of the otolith. The probe was pre-programmed to conduct a line scan from the central core to the edge. This provided a measure of the strontium concentration across the otolith from core to edge. A relatively low and constant Sr concentration across the otolith from core to edge is consistent with a nonanadromous life history where the char is exposed to a relatively constant Sr concentration in the water over the course of its life. A low Sr concentration in the core and early life of the char followed by a marked increase in Sr near the edge, showing a "spiked" pattern, is consistent with the life history of an anadromous Arctic char (Halden et al. 1996). The marked increase in Sr in the outer edge of the otolith is reflective of the much higher Sr concentrations in in seawater (8 ppm) compared with freshwater (0.1 ppm) (Rosenthal et al. 1970) and is believed to be accumulated during the chars' seawater feeding forays. Proof of anadromy is very important because the spawners captured in this study were taken in fresh water. Therefore, as many spawners as possible were examined in this way to determine their life history type. Also, mean Sr concentration in the otolith primordium was determined by taking an average Sr 47 concentration over the first 100 pm of the line scan (27 datapoints) in all cases where spawners were examined in this manner. Point analysis was carried out on specimens of nonspawners because this method was less costly than line scans. In this case, anadromy was known because the char were captured returning from the sea. The probe was directed at three random locations within the nucleus of each otolith examined. These points provided an absolute determination of Sr concentration for the very early life history of the char (Halden et al. 1995). The three point values were averaged for each specimen examined in this manner. Water samples were taken in acid washed bottles from the surface waters of Kitiga, Ferguson, Anderson Bay, Halovik, Char, Mount Pelly, Jayco, Lady Pelly and Wishbone lakes, and Freshwater Creek and Ellice River in August 1995. Water samples were taken with a Kemmerer sampler from a depth of about 2 m from Mount Pelly, Lady Pelly, Wishbone, and Jayco lakes in late August-early September 1996. A surface, mid- water and bottom water sample was taken in this manner from Ferguson Lake on September 2,1996. All samples were stored in acid washed bottles, kept refrigerated and examined in the laboratory at the Freshwater Institute for elemental composition by atomic absorption spectrometry. Mean Sr concentrations in the otolith nucleus were then compared with Sr concentrations in the water to determine if there was a correlation between environmental and otolith Sr concentrations. 48 Data Analysis All graphic displays and statistical analyses were carried out using the statistical software package Statistica (Version 5.5) by StatSoft Inc., Tulsa Oklahoma. When studying population affrnities it is necessary to separate nongeographic intraspecific variation from geographic variation. This nongeographic variation consists of intralocality variation, sexual dimorphism and ontogenetic variation (including allometry). Intralocality variation in single characters can be examined by the normal univariate statistics. Sexual dimorphism can be dealt with by keeping sexes separate and analyzing each separately. Allometric variation can be dealt with by various techniques (Thorpe 1976). All morphometric data were transformed (log,o) and regressed against standard length to determine the effect of size on each body measurement. Data from males and females were compared for each variable for evidence of sexual dimorphism (ANCOVA on log,o variable vs log,o standard length). These data were then subjected to an allometric adjustment to a standard size (539 mm, the grand mean of the standard length of all samples) to remove the effects of size differences between samples following Reist (1985). The common within-groups slope was used for the adjustment (Thorpe 1915, 1976) because of the possibility of within-groups heterogeneity (Reist i986). The common within-groups slope was calculated only from the samples of spawners because group identity of these samples was known and the slopes had biological significance. Samples of nonspawners were not included in the calculation of this slope because of the possibility that these samples were comprised of an admixture of more than one stock. However, the samples of spawners were taken from across the study area and were thus 49 assumed to be representative of nonspawners as well as spawners. The slope was calculated from the analysis of covariance program available in the ANOVA/MANOVA Statistica module. The adjustment for size was then carried out using the following allometric formulae from Thorpe (1975): A/\ ?¡: 1gYt where Y¡ : log Y¡ - b (log X¡ - logÐ and ^^.\f¡ is the adjusted character value of the ith specimen; I¿ is the logarithm of the adjusted character value of the ith specimen; I¿ is the original unadjusted character value of the ith specimen;X¿ is the standard length of the lth specimen; ii, the grand mean of the standard tength across all specimens.The allometric coeff,rcient å is the common within-groups slope. The data from spawners were compared for morphometric and meristic differences using forward stepwise Discriminant Function Analysis (DFA). Discriminant Function Analysis was used because it requires some knowledge of group membership and spawning aggregations were considered as representing homogeneous groups. Missing data were substituted by the overall means for the respective variables. The DFA was mn separately on the morphometric data and the meristic data because the former are continuous variables and the latter are discrete variables. The DFA provides a distance matrix based on the Mahalanobis D2 statistic. I used this distance matrix to provide an indication of the degree of morphological difference/similarity among the samples when all were compared simultaneously. 50 The Mahalanobis D2 statistic is a similarity coefficient (Mahalanobis 1936, cited in Thorpe I976) that is most popular as a mutivariate distance measure for continuous variables (Gould and Johnston 1972).It considers differences in means, variance and covariance of characters among groups. The information in a matrix of distance coefficients can be presented as a hierarchical diagram clustering the phenetically nearest neighbours and joining larger clusters at appropriate levels of mutual similarity (Gould and Johnston 1972). The morphological data for nonspawners was examined using Cluster Analysis because group membership does not need to be known. This method allows examination of a potential mixed sample to determine whether group structure exists within the sample. I used Cluster Analysis only as a first step to examine whether there was evidence of group structure because Cluster Analysis is useful for hypothesis generation (Anderberg 1973). Validation of clusters may be carried out in statistical or nonstatistical ways (Legendre and Legendre 1998). Where possible, I validated putative groups using morphological and genetic data. Amalgamation was by Unweighted Pair Group Method using arithmetic Averages (UPGMA). Euclidean distance, the geometric distance in multidimensional space, was used as a distance measure. All data were standardized to a mean of 0 and a standard deviation of 1. Missing data were substituted by the means for the respective dimensions. Output was a Vertical Hierarchical Tree Plot with specimen identification numbers on the horizontal axis. 5l Data from the electrophoretic analysis were tested for Castle-Hardy-Weinberg equilibrium within samples (chi-square goodness-of-fit) and gene frequencies were compared between samples by chi-square contingency analysis. The mtDNA sequences were compared following alignment with the MacVector program. The identity of two sequences is the percentage of shared bases and deletions, and insertions are scored as a single change, regardless of length following Hoelzel and Bancroft (1992). The ô'5N values were plotted against the ô13C and ô3aS values from the stable isotope analysis following Hesslein et al. (1991) to examine food source and trophic level of the samples tested. Strontium concentrations in the nucleus of otoliths from spawners were compared 'Water between locations by analysis of variance (ANOVA). Sr concentrations were compared with mean otolith Sr concentrations of spawners by location using correlation analysis. 52 RESULTS Comparison of Spawning Samples Discriminant Function Analysis (DFA) Sexual dimorphism was evident in seventeen of the nineteen morphometric variables used in this analysis (difference in means, p < 0.05). The two variables that did not exhibit evidence of sexual dimorphism were orbital length (OOL) and dorsal length (DOL). Sex ratios varied amongst most of the samples of spawners compared (Table 4). Table 4. Sex ratio of Arctic char spawners by location. Location Males Females Wishbone L. 25 35 Lady Pelly L. 39 12 Ferguson L. )z 13 Halovik L. 87 9 T/l 11 Halovik L. 93 2I JI Kitiga L. 14 9 Mount Pelly L.92 27 t7 Mount Pelly L. 93 6 5 Anderson Bay L. 93 25 6 Anderson Bay L.94 T9 9 a Fish Trap L. 8 J Char L. 20 26 Totals 245 r70 Therefore, the DFA was carried out separately on males and females, and then with the sexes combined. Results did not differ among these three data sets, and most of the variables that contributed to discrimination were the same in each case, regardless of sex. That is, differences between groups were greater than differences between sexes. The DFA using sexes combined is presented here to inciude the larger sample sizes. An example of the DFA by sex is included in Appendix I. In order to examine whether stock structuring was evident within a river system, I compared three samples of spawners from the lakes that were tributary to the Ekalluk River system. The plot of canonical scores from the discriminant function analysis of morphometric measurements made on Arctic char spawners from Ferguson, Lady Pelly and Wishbone lakes shows that the three groups can be readily distinguished from one another (Fig. 15). Root 1 shows the scores from the first discriminant (canonical) function for each individual specimen examined. This function contributes most to overall discriminatory power. Root 2 shows the scores from the second discriminant (canonical) function, which is independent (orthogonal) of the first function. It contributes less to overall discriminatory power. The results of the DFA are summarized in Table 5. All Chi- square tests with successive roots removed (0,1) were significant þ< 0.001). The variables that contributed the most to the discrimination included orbital length (OOL), maxillary width (MXVD, and lower gill arch length (LAL) in that order. Arctic char from Ferguson Lake have small orbits and those from Lady Pelly Lake have large orbits compared with char from Wishbone Lake (Fig. 16a). Char from Wishbone Lake have a naro\¡/ maxillary width compared with those from Lady Pelly and Ferguson lakes (Fig. 16b). Char from Lady Pelly Lake appear to have a shorter lower gill arch length compared with those from the other two lakes (Fig. 16c). Orbital length is shown plotted against maxillary width for each group (Fig. i7). It is evident from the above comparison that I was not able to obtain samples of spawners from all locations simultaneously. However, each sample was comprised of I 7 6 5 4 AA A 3 ß.4 ^ A ^nz A AA¡¡êiå A c{2 ^^ö À¡ÅÀ A õ1 ^âo^ o,^. oo É. trEFlg'a^a Á ^ - 0 tr nE i a tr B^ Bo À flftrstr Etr o -1 _E ço oo ";frPet" oo Ë Ej fF-j Sr""t o b -2 ro#Eätrtr" o tr Etr # -3 ntr tr trtr -4 -5 -6-4-202468 10 Root 1 Figure 15. Discriminant function analysis of morphometric measurements of Arctic char spawners from Ferguson, Lady Pelly and Wishbone lakes in the Ekalluk River system. 55 Table 5. Summary of the discriminant function *ulyri, of morphometric measurements of Arctic char spawners from Lady Pelly, Wishbone and Ferguson lakes. STAT. DiscriminanÈ Function Anal-ysis Summary DïSCRIM. Step 10, N of vars in model-: 1-0,- Grouping: GROUP (3 grps) ANÃI,YSIS WiLks' Lambda: .05260 approx. F (20,288) =48.387 p<0.0000 W1l-ks' PartlaL F-remove l--To1er. Lambda Lambda (2,]-44) (R-sqr. ) LOGOOL .1,20252 . fr5 /f+l-b >2.ôusuy .000000 .087 07 9 LOGivD(I^l .087560 . ÞUU /5.J 47.85351_ .000000 . õ.¿Þb5+ LOGLÃL .066569 .7901_58 L> - L¿V>ó .000000 . oÈt+ltr+ .JIJ-L''b LOGCPL . UO-5Þ-5Z .826638 1 C ôOO?O .000001_ .738955 . zo Lv+5 LOGANL .062205 .845594 1a 1¿.'Ìta .000006 .622359 .377 64]. LOGBDD .0557 54 .943432 4.3l-707 .0L51_07 .723560 .276440 LOGTTL . UÞ-5Þ25 .826727 r-5.09040 .000001_ .495r-l_9 .504882 LOGDOL .063537 .827868 t4 .97 037 .000001 .4L4084 LOGLUL .063557 -ó¿ toJ-L !+.J>t3ó .000001_ . a¿v Ló+ -+ t>ó!6 LOGPSL - ua6zöz . 934s8 9 . uu /obu .566694 .433306 56 1.?2 1.16 J f t.to I *1.96'Std. Dev. a Ef t1.00'Std. Dev. U.Y'' o Meãn 0.98 TT 0.92 t-,--] =x .r.tr = 9 o.æ H_r_ 0.80 È1.96'Std. Dev. E- t1.oo'Stcl. Dev. 0.74 br o Mean t.t 1 1.70 TT 1.68 1.66 J TÜ+ of r.e¿ o l 1.62 Ãl ll 1.60 I l-T-+ 1.58 T ñq, -i-l r1.96'5td. Dev. r1.oo'Stcl. Dev. {E E Mean LADY PELLY L. WISHBONE L. FERGUSON L. Figure 16. A comparison of mean tog (a) orbital length (OOL), (b) mærillary u'idth (ND(W), and (c) lower gill arch length (LAL) among samples of Arctic char spa\ryners from Lady Pelly, Wishbone and Ferguson lakes. 1.04 oo 1.00 o 0.96 g"Þff". 0.92 oo%to o oo 0.88 ooo '*î*u., 0.84 i . "J"ä õr"b 0.80 :tr oo o t- oo Ô Ê 0.76 0.72 0.98 1.02 1.06 1.10 1.14 1.18 1.22 1.26 1.30 0.98 1.02 1.06 1.10 1.14 1.18 1.22 1.26 1.30 É.= LADY PELLY WISHBONE L. J L. J 1.04 1.00 = oqeo (t 0.96 "E o .oo J 0.92 ffiu"3"o O.BB 'oooo 0.84 0.80 0.76 0.72 0.98 1.O2 1.06 1.10 1.14 1.18 1.22 1.26 1.30 FERGUSON L. LOG ORBITAL LENGTH Figure 17. A plot of log orbital length (OOL) against log maxillary width (MXW) for Arctic char spawners from Lady Pelly, Wishbone and Ferguson lakes. 58 multiple year classes of Arctic char. Values of morphological characters consistent across all year classes within each sample provide evidence that the morphological differences observed among samples were not a product of year-to-year variations based on samples taken in different years (Fig. 18). Additionally, due to the range of year classes present in most samples, the same year classes were present in a number of samples although the samples were taken in different years. In order to examine whether stock structuring was evident among river sysems, I compared samples of spawners from a number of geographically adjacent river systems. The DFA on morphometric measurements of Arctic char spawners from the three river systems draining into Wellington Bay shows that group separation is evident among spawners from Ferguson Lake, Halovik Lake and Kitiga Lake (Fig. 19). All Chi-square tests with successive roots removed (0,1) were significant (p< 0.001). Variables contributing most to the discrimination included caudal peduncle length (CPL), maxillary \^/idth (MXUD, head depth (HDD) and orbital length (OOL) (Table 6). All Chi-square tests with successive roots removed (0,1,2) were significant @ < 0.001). A relatively smali orbit (Fig. 20a) characterizes Ferguson Lake spawners. Kitiga Lake spawners appear to have a narrow maxillary width (Fig. 20b) and smaller head depth (not shown) relative to those from Ferguson Lake and Halovik Lake. Halovik Lake (1993) spawners appear to have a longer caudal peduncle (Fig. 20c) than the others. Differences in mean maxillary width (Fig.20b) and caudai peduncle length (Fig. 20c) are evident between the Halovik Lake 1987 and 1993 samples. Orbital length is shown plotted against maxillary width for each group (Fig. 21). A wide range in orbital length is evident for the Halovik Lake 1993 spawners (Figs. 20a,21). 22 o 20 o o o 1B cDocD o o ooo o oooo to CDO oæ ooo o o ooo oÐ oo o 14 ooco oo o o o @co 12 o 10 B 0.98 1.02 1.06 1.10 1.14 1.18 1.22 1.26 1.30 0.98 1.02 1.06 1.10 1.14 1.18 1.22 1.26',t.30 LADY PELLY L. WSHBONE L. ul (, 22 o 20 18 oo 16 o oo o o coo oo 14 oooo@o ooæo 12 cDo 10 B 0.98 1.02 1.06 1.10 1.14 1.18 1.22 1-26 1-30 FERGUSON L. LOG ORBITAL LENGTH Figure 18. A plot of log orbital length (OOl).against age for Arctic char spawners from Lady Pelly, Wishbone and Ferguson lakes' 6 5 4 3 **n* wt6 E o + E 2 s Ë E E o* E + ooo Ëo þ o 1 o c\¡ Eqþ fie o fio o ooo o o oo:.3 oJ ó o ogo oo oo 0 ,, E-o eo o É o"gf;o"oo i* ** ú + o -1 tr soo # tr o ooo 4""";EFoooo -2 o trtrootrtr o tr -3 -4 -5 4 5 -4 Root 1 measurements of Arctic char 19. Discriminant function analysis of morphomet-ri9 Figure Kitiga Lake and ,pu*rr"r, irom Halovik Lake 1987, Hhovik Lake 1993, Ferguson Lake' 61 Table 6. Summary of the discriminant function analysis of morphometric measurements of Arctic char spawners from Halovik Lake 1987, Halovik Lake 1993, Kitiga Lake and Ferzuson Lake. SÎAT. Discriminant Function Analysis Summary D]SCRIM. Step 10, N of vars in model: l-0,' Grouping: GROUP (4 g'rps) ANALYS]S WiLksr Lambda: .08017 approx. F (30,352)=L6.028 p<0.0000 W].IKS' Partial F-remove 1-Toler. NT_1 ? ? Lambda Lambda (3,l_20) n- I a¡¡o ì Toler. \¡\lÞ-(ar vY¡., I -Ì LOGBDD 094732 846329 .26292 000r.62 5U4 þ15 495385 LOG¡Ð(W 107888 7 43]30 !J . ö¿OJ I 00 000 0 ö450öt 1_563L9 LOGCPL Lt2357 7L3573 1 6. 05596 000 00 0 '7 387 34 ¿or¿oo 097308 823924 8.54818 00003 4 902334 097 666 !vgJru 093472 857 7 38 o . oJ¿IZ O 00 034 I 6vó¿ I 3 5Ur | ¿a LOGHDD 098135 816986 8.96042 00002 1 508966 49]034 !\J\J\f.ñ! 093702 I 55637 þ. / ¿lõúl_ 000303 844961 1 55033 LOGLUI, 093384 858551 o. Jvul_r 0003 68 7 06497 293503 LUbrò! 0I91-14 899687 4 .45992 005241 664646 55JJJ¿I LOGCPD 088328 90'7 692 4.06187 00 I 604 531740 468260 62 1.26 | .24 1.18 r 1.14 o Y r.¡v 1.06 Á!ì --f- t1.96'std. Dev. d l-l t1.00'Std. Dev. 0.98 o Mean rñA 1.O2 0.98 0.94' 3 f o.so - 0.86 0.82 n7a -T- t1.96'Std. Dev. T--] t1.oo'Std. Dev. 0.74 o Mean ¿.v¿ ¿.uu 1.98 -¡ 1.96 r.sa $J 1.92 1.90 1.88 ï 11.96'Std. Dev. t1.00'Stcl. Dev. 1.86 - Mean HALOVIK L. HALCVIK L. KITIGA L. FERGUSON L. 1987 1993 Figwe 20. Acomparison of mean log (a) orbital length (OOL), (b) maxiilary width (lvD(W), and (c) caudal peduncle length (CPL) among samples of Arctic char spawners from Halovik Lake 1987, Halovik Lake 1993, Kitiga Lake and Ferguson Lake. 1.08 1.02 o ooo o% o 0.96 o ,"- o oo o@ 0.90 Bo ooo oo-o oo 0.84 :;q-$r o ot- 0.78 o.72 0.98 1.O2 1.06 1.10 1.14 1.18 1.22 1.26 0.98 1.02 1 .06 1.10 1.14 1 .18 1.22 1 .26 É= HALOVIK L. 1987 HALOVIK L. 1993 5 1.08 ã 1.02 c, 0.96 o oo o s"% $e. 0.90 oo @ o q"d t""" ooo 0.84 o oo B 0.78 " 0.72 0.98 1.O2 1.06 1.10 1.14 1.18 1.22 1.26 0.98 1.02 1.06 1.10 1.14 1.18 1.22 1.26 KITIGA L. FERGUSON L. LOG ORBITAL LENGTH Figure 21. Aplot of log orbital length (OOL) against log maxillary width (MXW) for Arctic char spawners from Halovik Lake 1987, Halovik Lake 1993,Kitiga . Lake and Ferguson Lake. 64 Segregation is apparent in the morphological comparison among Arctic char spawners from Kitiga Lake, Freshwater Creek (Mount Pelly Lake 1992) and Anderson Bay Lake (1994), (Fig.22). The morphometric variable that contributed most to this discrimination was gill raker length (GRL) followed by dorsal length (DOL), trunk length (TTL) and pectoral fin length (PCL) (Table 7). All Chi-square tests with successive roots removed (0,1) were significant (p< 0.001). Spawners from Mount Pelly Lake 1992 were characterized by relatively short pectoral fins (Fig.23a), long dorsal length (Fig. 23b) and long gill raker length (Fig 23c) compared with those from the other two locations. Spawners from Kitiga Lake had short dorsal length (Fig. 23b) and gill raker length (Fig. 23c) while those from Anderson Bay Lake (1994) had intermediate values for these variables but a short trunk length (TTL) (not shown) compared with the other two groups. A plot of dorsal length against gill raker length is shown inFig. 24. The results of the DFA between Mount Pelly Lake 1992 md 1993 and Andelson Bay Lake 1993 and i994 shows that group structure is evident between Anderson Bay Lake 1993, Anderson Bay Lake 1994, and the two Mount Pelly Lake samples (Fig. 25). Discrimination between the two Mount Pelly Lake samples is not evident here. Chi- square tests with successive roots removed (0,1) were significant (p< 0.001). The variable head depth (HDD) appears to have contributed most to this discrimination (Table 8). Body depth (BDD), orbital length (OOL) and pectoral fin length (PCL) also contributed. Both samples from Mount Pelly Lake,1992 and 1993, had similar small mean head depth while those from Anderson Bay Lake 1993 a larger mean head depth than those from Anderson Bay Lake 1994 (Fig. 26a.). Both samples from Mount Pelly Lake had similar body depth while those from Anderson Bay Lake 1993 had the smallest body depth 4 trtrtr trtrtr tr oo trtru ";;B:" tru trtr @o #E oo c\ oo or*o õ0o o n E É. ": ooå ^^ -1 s Soo la oa ^^ A r4^ a AA A A ^ -6 -5 01 2 3 4 5 6 Root 1 Figure 22.Discriminant function analysis of morphometric measurements of Arctic char spawners from KitigaLake,Mount Pelly Lake t992 and Anderson Bay Lake .1994. 66 Table 7. Summary of the discriminant frmction analysis of morphometric measurements of Arctic char spawners ûom Kitiga Lake, Freshwater Creek (Mount Peliy Lake) 1992, and Anderson BaY Lake 1994. STAT. Discriminant Function Analysis Summary nTcl-ÞTM Step 11, N of vars in model: 1l-; Grouping: GROUP (3 grps) ANA¡YS]S Vlilks ' Lambda : .L137 4 approx. F (22'I64J=I4.649 p< .0000 !,iilks' Partial- F-remove l--ToIer. /Þ-(ar ) T,ambda Lambda (2, 82) p-1eve1 ToIer. \¡\ vY5. N=95 ' IJU\ rU! T4 I ¿ö3 7'1227 6 t2 08986 000025 Jöb54J O-LJOJ / !uþ(fl1! t6'7249 68 0091, 19 ZöOUI- 00 000 0 / JOJO¿1 ¿r+.J0Jo a '7 LOGOOL ]-20664 Y'f ¿OJJ ¿ 4942s 08 I 804 69982 23 0 018 '723451 LOGÐOL ]-57225 -LJ 6721 8 00 0 002 400657 599343 LOGTTL 15JL / J '7 42580 I4 2r288 000005 413160 58 6840 '1 !\J\lrv! 134213 847tr7 39946 001 11 1 396806 603t94 !uglru I2 8118 I 5098 6 000438 OIIJ / O 388624 LOGPVI, r2'7262 893781 87 254 010011- 3232r0 61 67 90 LOGHDD 729458 ó I óOZ4 5 66389 004965 3 65848 634152 ¿Ib LOGCPD 15öIðO 823]-24 I gto23 oo0342 / Jro 532684 ¡t¿+I¿lJJ !Lr(JÞlJ!/ L28049 888289 5 -15þr / o0777 5 5þö54 / 67 l- z.vz J t-"1 T, r.ss Io --r- | ll _ | t.ff HTIlltl 1.90 __[ -f- t1.96'Std. Dev. .ñ El t1.oo'std. Dev. ínA tr Mean 1.94 1.90 T {A^ t- r 1.82 I lr-t I o 9 1.78 +rt t[-"l 1.74 _l_ l- L_l 1.70 _l_ -T- t1.96'Std. Dev. b l--1. t1.00'Std. Dev. 1.66 o Mean 1.05 0.95 0.85 J J 0.75 nAq :I t1.96'Std. Dev. nçq tl t1.00'Std. Dev. o Mean N.qOU$'lT PELLY L. ANDERSOId BAY L, KITIGA L. 1992 1994 Figwe 23. Acomparison of mean log (a) pectoral fin length (PCL), (b) dorsal length @OL), and (c) gill raker length (GRL) rlmong samples of Arctic char spawners from Kitiga Lake, Mount Pelly Lake 1992 andAnderson Bay Lake 1994. 1.15 1.05 o o 0.95 oo ooo g t$%ooooo o 0.85 eA "."€ &3t O6 ocqö o& 0.75 o g t- 0.65 zC' 0.55 ¡.u 0.45 1.74 1.78 1.82 1.86 1.90 1.94 1.98 2.02 É. 1.70 1.74 1.78 1.82 1.86 1.90 1.94 1.98 2.02 1.70 ul ANDERSON BAY L. 1994 \¿ MOUNT PELLY L. 1992 1.15 É. 1.05 J oo õ 0.95 ('9 o 0.85 oA s go o o o.75 oø oos o 0.65 (o o 0.55 o 0.45 1.70 1.74 1.78 1.82 1.86 1.90 1.94 1.98 2.02 KITIGA L. LOG DORSAL LENGTH Figure 24. Aplot of log dorsal length (DOL) against log gill raker length (GRL) for Arctic char spawners from Kitiga Lake,Mount Pelly Lake 1992 arÅAnderson BayLake 1994. 5 tr BEtr tr trtr tr A otr c\¡ Ël¡g ED tr ¡tr Ë1 ^ o a ^laA ÅA o'¡ M. l a^ og lor Êtr a4 o A A -oo"o A tÐ -og o oo -1 A + a &ooo' oüotr A ^a o oo + o oo o -3 -6 -4 -2 0 2 4 6 Root 1 Figure 25. Discriminant function analysis of morphometric measurements of Arctic char spawners from Mount Pelly Lake 1992 and 1993 and Anderson Bay Lake ' 1993 andl994. 70 Table 8. Summary of the discriminant function analysis of morphometric measurements of Arctic char spawners from Mount Peliy Lake 1992 arñ 1993, and Anderson Bay Lake 1993 and1994. STAT. Ðiscriminarit Function Analysis Sunmary DISCRTM. Step 6, N of vars in model: 6; Grouping: GROUP (4 grps) ANA.],YSIS Wil-ksf Lambda: .]-1,2'7'7 approx. F (I8t297) =19.224 p<0.0000 Wil-ks' Partial- F-remove l--ToLer. af-1 1 ¡ t\-f¿= Lambda Lambda (3,105) n- I ar¡a'l Tol-er. lÞ-(nr\¡\ vYÀ . /ì LOGHDD 27 0609 4167 09 48.99155 000000 47 6449 52355r_ LOGBÐD roy¿+t_y 6 65597 1 7 \P, ¿.?7 0 0 0000 460291 53 97 03 LOGOOL r_ 52101 I4TJó¿ t2.20914 00 0 001 946073 VJSY¿ I LOGPCL 145rU5 '7'77I2'7 10.03767 00 0 007 8297 60 t7 0240 LOGlo(W özYz55 7 .207 69 0 00191 ót tSzo rz¿o I 4 LOGCPD 1 332 08 84 6534 þ. J45U / 000538 4 587 59 541,241" 7l 1.82 T __.1_ 1.78 ËJl U " ?tn l- T |-r-r"l lll tt+ll"ll"lllr 1.66 -T-r I t^ t1.96'Std.Dev. a Ef- gt.00'Std. Dev. 1.62 o Mean 2.20 2.16 -r 2.12 -T----T-- l*l a 2.08 rl o I 2.04 L:Jl"lf-:LJ | --r-lrlll " | | 2.00 1.96 ]I *l.ge'st¿.Dev. bl Ef t1.00'Std. Dev. 1.92 o Mean 2.10 -T- ll I -T-l-ll"lttl I r.se I I I s o ll I i r--ri rt I oJ o | | 1.94 I ll ll |llr,rll tr tt | | I tl 1.90 I Ï t1.96'Std. Dev. c l-l t'|.00'Std. Dev. B Mean MT. PELLYL. !âT. PELLYL ANDERSON B. L A.NÐERSON B. L 1992 1993 1993 f994 Figure 26. Acomparison of mean log (a) head depth (I{DD), (b) body depth @DD), and (c) pectoral fin length (PCL) among samples of Arctic char spawners from Mount Pelly Lake 1,992 and 1993 and Anderson Bay Lake 1993 and t994. 72 of all groups and those from Anderson Bay Lake had the largest body depth of all groups (Fig. 26b). Both Mount Pelly Lake samples had short pectoral fins while those from Anderson Bay Lake lgg4hadthe longest pectorar fins of all four samples (Fig. 26c). Orbital length contributed to discrimination in root 3 (not shown) with samples from Mount Pelly Lake 1993 having the smallest mean orbital lensth of all four groups. The relationships of the variables head depth and body depth for these groups is shown inFig.27. The Anderson Bay Lake 1993 sample appears to be the most distinct when compared with Anderson Bay Lù Lake and Fish Trap samples were similar with respect to body depth and head depth but the Fish Trap Lake sample had the smallest mean orbital length although the range of the values of this variable was wide (Fig. 29c). The relationship of the variables body depth and head depth for these groups is shown in Fig. 30. A discriminant function analysis of all twelve samples of spawners from across the study area was car¡ied out to identiff similarities/differences among the groups. All Chi-square values with successive roots removed (0, 1-6) were significant at p < 0.001, and root 7 removed at p : 0.01. The swnmary of the DFA (Table 10) indicated that 2.18 2.14 o 2.10 o ooo 2.06 oo oõ o o oB 2.02 "^€M*",'ooo oo 1.98 1.94 l-r o- 1.90 tUo 1.58 1.62 1.66 1.70 1.74 1.78 1.82 1.86 1.58 1.62 1.66 1.70 1.74 1.78 1.82 1.86 MOUNT PELLY L. 1992 MOUNT PELLY 1.1993 o 2.18 o o m Q%o o 2.14 o o o o \ì o 2.10 oo t oo UJ 2.06 o o o^og . t""'"n 2.02 " oo o 1.98 "i.o[æ o 1.94 o 1.90 1.58 1.62 1.66 1.70 1.74 1.78 1.82 1.86 1.58 1.62 1.66 1.70 1.74 1.78 1.82 1.86 ANDERSON BAY L. 1993 ANDERSON BAY L. 1994 LOG HEAD DEPTH Figure 27. A plot of log head depth (HDD) against log body depth (BDD) for Arctic char spawners from Mount Pelly Lake 1992 andl993, and Anderson Bay Lake 1993 and 1994. aa A a o tr tr tr o tr ^ aa C\¡ tr o tr tr Ë1 o-o ^^ {^ o o trtr trtrtr ^oï^4o o É. tr otr - F trn + ^û ôr a o tr ^"^;r.,oo -¡ "tr+ tr ** -1 tr tr o tr S;oo3olg o tr_o o ++ü o + -4 -5 -4 -3 ,2 -1 0 2 3 4 Root 1 Figure 28. Discriminant function analysis of morphometric meastuements of Arctic char spawners from Anderson Bay Lake 1993 and 1994, Char Lake and Fish Trap Lake. 75 Table 9. Summary of the discriminant function analysis of morphometric measurements of Arctic char spawners from Anderson Bay Lake 1993 and 1994, Chat Lake and Fish Trap Lake. STAT. Discriminant Function Arral_ysis Summary DTSCRIM. Step 7, N of vars in model_: 7; Grouping: GROUP (4 grps) .ANA¡YS]S Wil-ks' Lambda z .20956 apÞrox. F (21.t304)=10.502 p< .0000 lVil-ks I Partial F-remove l--ToIer. 1\:l- J_ O Lambda Lambda (3,106) p-1evel ToIer. (R-Sqr. ) LOGHDD ¿t455t 763804 ru . Y¿osz 000003 613 8 08 3861,92 LOGBDD JU / -LJO 682287 16.45326 000000 JYOVZZ 60397 I LOGOOL ¿o I 5ó6 I óJ!5¿ 9.'78461 00000 9 óo¿J¿5 LJ14I I LOG¡Ð(W 2501-7 6 837630 6.849L1 0002 91 824653 t7 5347 LOGTT], 249540 ö5vt6t þ. /41ö5 00033 1 /b/5rö ¿5¿4óZ LOGA-D], zJ>oo I 87 436I 5.07713 002526 I 87 057 172943 LOGCPD z5tJtó 882047 4.12500 003909 JO¿554 637 466 76 216 T:L Ltz lrll l,ll"l 208 o I f1 l.ll l+r aLu J -_l-t| |"tlttl l+ tl " I I L00 tltl | -T- 1.96 I r1-96'Std.Dev. a f-]- t1.00'Std. Dev. 1.92 o Mean 1.84 t.ad 1.76 ttz o? o 1.68 1.64 lE t1.96'Std. Dev. E= 11.00'Std. Dev. 1.60 o Mean 1.26 1.20 1.14 J 8 t.oe I 1.0? 0.96 11.96'Std. Dev. G f--l- tl.oo'std. Dev. 0.90 o Mean GHAR L FISH TRAP L ANDERSON B. L ÀNDERSON B. L 1991 1991 1993 1994 Figr:re 29, Acomparison of mean log(a) body depth (BDD), (b) head depth (IIDD), and (c) orbital length (OOL) among samples of Arctic char spawners ûom Anderson Bay Lake 1993 and 1994, Char Lake and Fish Trap Lake. 2.18 o 2.14 @o o 2.10 o"oo O9 oo 2.06 8n oo "d**oo o oo 2.02 o-% äo o ooo o 1.98 1.94 t-:E ù 1.90 olrJ 1.58 1.62 1.66 1.70 1.74 1.78 1.82 1.86 1.58 1.62 1.66 1.70 1.74 1.78 1.82 1.80 CHAR L. FISH TRAP L. o 2.18 o o c0 2.14 9oo o o., o -J o 2.10 o 3 \ì oo g oo 2.06 o o o¡Q g o ot?3"8" 2.02 ooo 1.98 'i.o[æ o 1.94 1.90 1.58 1.62 1.66 1.70 1.74 1.78 1.82 1.86 1.58 1.62 1.66 1.70 1.74 1.78 1.82 1.86 ANDERSON BAY L. 1993 ANDERSON BAY L. 1994 LOG HEAD DEPTH Figure 30. A plot of log head depth (HDD) against log body depth (BDD) for Arctic char spawners from Anderson Bay Lake 1993 and 1994, Char Lake and Fish Trap Lake. 78 Table 10. Summary ofthe discriminant function analysis of morphometric measurements of A¡ctic char from the twelve sarnples of spawners examined across the study aÍea. ST.A,T. Discriminant Function Aaalysis Summary DÏSCRIM. Step 12, N of vars in model: 1,2; Grouping: GROUP (12 grps) ANALYSIS V[ilks 1 ],ambda z .02989 approx. F (1"32,3225) =13.085 p<0.0000 hlilks I PartiaL f'-remove 1-Tol-er. 1\=q r 5 n-'l arza l Lanbda Lambda !It 5Y¿ Toler. (R-Sqr. ) ¡octDtw .041 99r 622860 2t 0 000000 8't 4414 12558 6 . 0512 60 ¿3 4751 I 0 0 0000 0 914888 08 51 12 11 LOGCPL .039549 7 55 825 II 5r_2 59 00000 0 806292 1937 0 I LOGBDÐ .040865 /Jr4ú5 -LJ 08160 0 0000 0 52078L 41921_9 !vg.ru .VJIJYY 7 99260 ö 0 0000 0 O O.L YJJ 338 0 67 TOGHDD .042494 1 03432 0243L 0 000 00 35Lr¿4 46887 6 !ULrtf.r(Ir .038763 I I LI.5ó 10 J/OJ4 00 0000 9031.72 09 682 I !tJ\f ur.| . vJoó¿ I örroYz I 267 44 0 00 000 53 594 6 464054 n?qÁ?-r LOGPCL OJõYJJ 6 84186 000000 77658s Z¿J'!IJ LOGANL . 0351 09 8514 05 6 000000 7 44690 ZCJS I- U LOGIOV{ . UJJYJ4 I 803 60 4 84294 000 001 584 1 99 415801 LOGLUL .v553¿C 891 655 4 3301-9 000004 I JA44L 79 orbital length (OOL) contributed most to the overall discrimination of groups, followed by maxillary width (lvlx\Ð and head depth (HDD) in that order. Spawners from Lady Pelly Lake had the largest mean orbital length of all groups (Fig. 3 1a), while those from Ferguson Lake, Mount Pelly Lake 1993 and Fish Trap Lake had the smallest mean orbital length. Analysis of variance (ANOVA) revealed significant differences Cr< 0.01) in mean orbital length between some groups. A Least Significant Difference (LSD) test provided probabilities for differences between all pairs of means (Table 1l). Spawners from Lady Pelly, Ferguson and Halovik (1987) lakes had the greatest maxillary width of all groups (Fig. 3lb) while those from Mount Pelly Lake 1993 and, Anderson Bay Lake i993 had the smallest maxillary width. Significant differences (ANOVA, p < 0.01) in mean maxillary width existed between some groups across the study area (Table 12). Spawners from Lady Pelly Lake and Anderson Bay Lake 1993 had the greatest head depth of all groups (Fig. 31c), while those from Kitiga Lake, Mount pelly Lake 1992 and 1993 had the smallest head depth. Significant differences in mean head depth (ANCOVA, p < 0.0i) existed between some groups (Table 13) across the study area. The dendrogram (Fig. 32), based on Squared Mahalanobis Distances (Dt) calculated from the discriminant function analysis of all twelve samples of spawners from across the study area (Table 14), reveals similarities among them. The samples from Char Lake and Wishbone Lake appear to be the most similar to one another. The samples from Anderson Bay Lake 1993 and Ferguson Lake are dista¡rt from the first eight groups. Halovik Lake 1987 and Lady Pelly Lake samples, although distant from one another, appear to form a group of their own, quite distant from all other groups. 80 1)q -T- 1a^ T-l- | T .- Itrl| I r-l-:-r\ -T| J--l- | I | -_r_l I | | | r-\l | | | { rà r l- | l.ll" llll" l- l" ll" ll-lÅ l" 4l I l.f,lLJLl+'\+J.fl"14 I | | t | | ll I J rrlolr -l ll"l I l-l"l oO rnc -L ï t--l*r -T- noq I tt.g€'Std. Dev. AI f---'l t1.oo'Std. Dev. 0.90 t Mean {ôq 1.00 T -rT noq Fl r[f l'lÅ- r -,- ÅI.- 0.90 ïËî1HÉÉür[]Fü ñÊq-'-- xts õ o.8o ? |'--.-*,| | | l-T-+r || --l- 4 q I IIÏ' - 0.75 lI t1.96'std.Dev. T--] r1.00'Std. Dev. b o Mean T 1.80 | - 1.76 t.trïtùlÅ.Ll tl tt tTTrl'll n.l- lJ-Å ' 1.72 ll "ll o *l'lLJlLil "ll "lÅ'l.lîl'lill "l T lLJl " ll" ll " l r I ll" ll 'l $ r.oe J 'LJ lrIffl TLJÇ l*l I l-r- I I 1.64 I-L ' I II -Ï- t1.96'Std. Dev. .ñ '\J T-1 t1.00'Std. oev. 1.60 o Mean ". (o äH ËÈËÈE $H:: ã JjiPgS::rirj=.:y6 r I q;; HH3==i'J#þÞ:ëI ="6 Ë d 3 3 tr * * i Ë Ë EEi # Figure 31. A comparison of mean log (a) orbital length (ool), (b) maxiliary v¡idth (IVD(W), and (c) head depth (HDD) among the twelve samples of Arctic char spawners examined across the study area. 81 Table i 1. A comparison of all pairs of means for the morphometric measurement log orbital iengfå (OOL) among the twelve samples of Arctic char spawners examined across the study are4 using the Least Significant Difference (LSD) test. (+ : minimum 0.05 significance level) STAT. LSD test; variable LOGOOL GENERAL Probabilities for post Hoc Tests MÃ,NOVA. MATN EFFECT: GROUP {1t I?T {3} t¿Il {s} {6} u.È(uur 1.127801 1.070281 1 . 1410 02 !. L¿t¿>¿5 L.131470 I.ADY PELLY L. l1I 000000* 0.000000* .000010* 000000* 00 000 0* WISHBONE L. t2t .000000* .000000* .¿JOq I r 041352* Áq?n1? FERGUSON L; t3l 0.000000* 000 000* .000000* 000000* 000000* HALOVIK L. 87 t4l .000010* ¿464 I L .000000* 469822 HALOVIK L. 93 t51 .000000* 04 1352* .000000* .ó9 t ro I 245687 KITIGA L. t6l .000000* .000000* .10YóZZ ¿456é I MT. PELLY L 92 t7l .000000* o04299* .000000* .48L694 37 4252 UþþÐÞZ MT. PELLY L 93 t8I .000000* 000015* . õJ-JU¿1þ .00001_7* 00 000 0* 000036* ANDERS. B. 93 | /lát I L tsl .000000* .000000* . 988 658 843583 37127 6 ANDERS. B. 1.94 10l * t .000044* 00090 0 .000000* .2L37 84 1 077 95 01?917* CHAR L. 111 t .000000* .000000* .ZUöI-bJ 03l_7 99* 57 0 635 FISH TRAP L. Í.12) .000000* 000015* .ö¿vYu I .000017* 000000* 000035* STAT. LSD test; variable LOGOOL GENERAL Probabilities for post Hoc Test,s MANOVA M¡,IN EFFECT: GROUP fRÌ i7) {e} { 10 } f11t I1)l GROUP 7.149444 L.07327 0 L.t40824 L.LJOöt¿ J..IZÐYO:) L.Vr3rt4 I.ADY PELLY L. t1l 0 0000 0* 0 00000* .000000* 000044* 0 00000* 0 00 000* WISHBONE L. t.21 Q04299* 00001 5* . I¿Ió IJ 000 900* I 05337 000015* FERGUSON L. t3l 00 0000* 815046 .000000* 000 00 0* 00000 0* 82 0907 HALOVIK qReÁqa L. 87 t4I 481,694 000017* 213784 2 0 8165 00001 7* HALOVIK L. 93 t51 37 4252 0000 0 0* . ð¿{J5öJ LU I IYJ 031 7 99* 000000* KITIGA 1., tçI 066562 0 0003 6* .JIL¿IO 0I7 917* 570635 000035* MT. PELLY 1.92 * q,co* 1.7 I 0 00000 nn? 0 0000 0* MT. PELLY L 93 t8l 000 00 0* .000001* 000 000* 0 0004 3* 995252 ANDERS. B. * 1.93 teI 0 00001 IUJöI-1 092989 000 001* ANDERS. B. L 94 I 101 4 r.8 935 000000* .IU5ðJ_1 000753 * 000000* CHAR L. 111 l 003559* 00 0043* .092989 000753* 000042 * FISH TRAP L. | 121 000000* YY J¿J¿ .000001* 000000* 000042* 82 Table 12. A comparison of all pairs of means for the morphometric measurement log maxillary width OÆffi) among the twelve sampies of Arctic char spawners exarnined across the study are4 using the Least Significant Difference (I-SD) test. (* : minimum 0.05 significance levei) STAT. LSD test; variable LOG¡,Ð(9,I GENER-âL Probabilities for Post Hoc Tests MANOVA MAIN EFFECT: GROUP f 1Ì t?l {3} {¿} fqÌ tol GROUP .944t499 862681 4 .9400857 . v¿1 0Jruo 8866708 .8491483 LADY PELLY L. l1l 000000* 64894L 000000* 00 00 00* WISHBONE L. 1.21 000000* 000000* 000000* 003910* ¿UþJ5J FERGUSON L. t31 64894t 000000* 6401_78 000000* 000000* HALOVIK L. 87 l4l öOI /:'J 000000* 640178 000012* 000000* HALOVIK L. 93 t5l 000000* 003910* 000 000* 000012* 000 653* KITIGA L. t61 000000* Z U OJ55 000000* 000 000+ 000 653* MT. PELLY L 92 t7| 000000* 032 450* 0 00000* 000000* 000003* MT. PELLY 1.93 t8l 000000* Q04'7 48* 0 00 000* 000 00 0* 000010* 09108 6 ANDERS. B. L 93 tet 000000* 000467* 000 000* 000 00 0* 000000* 088500 't ANDERS. B. L 94 t 101 000000* 00 647 3* 000003* 000132* 44052 0 00951* CHAR L. l11I 000000* 0249t2* 0 00000* 00 000 3* 5YIþU¿I 0 03438* FISH TRAP L. 112 ) 0000 00* 9L3944 000000* 00 000 6* r2r937 J¿IJYYõ STAT. LSD test; variable LOG¡Ð(W GENER.¡\L Probabilities for Post Hoc Tests I4ANOVA MAIN EFFECI: GROUP 4141 {7} fRt f1nÌ { 11} þltUUT .844r.069 .ó¿¿u03 I .828652t aonñ1 1? .8819304 .8642344 * * LADY PELLY L. 0000 00* 000 000 000 000 000 000* 000 00 0* .000000* l1l yJ-Jy¿l¿l WISHBONE L. t2l 032450* 0047 48* 0oo4 67* 00 6473* 024912* . FERGUSON L. t3l 000000* 000000* 0 000 00* 00 0003* 000 0 00* .000000* HALOVIK L. 87 t4t 000000* 000000* 000000* 000132* 00 00 03* .000006* HALOVIK L. 93 t5l 000003* 000010* 000000* 7 44052 . L¿LY3 I KITIGA L. t6l b555J r 09r_08 6 08 I 500 00 0 951* 00343 8* . J45v9U MT. PELLY L 92 t7l IJ¿l OqJ 000017* 000048* 1 11 1q-1 MT. PELLY L 93 t8l 134645 661234 0000 1 5* 0 00052* .023901* ANDERS. B. L 93 tel rJ 15Þv oo I ¿J4 000000* 000000* .020596* ANDERS. B. L 94 t 10l 0 000 17* 000015* 000000* 440019 CHAR L. 11l 000048* 00 0 052* 000 0 00* 440019 .¿¿t135 t q"6 FISH TRAP L. 1.12) Ltrt>r 023901* 02 0596* no? 227 453 83 Table 13. A comparison of all pairs of means for the morphometric measwement log head depth (HDD) among the tweive samples of Arctic char spawners examined across the study area, using the Least Significant Difference (LSD) test. (* : minimum 0.05 significance level) STAT. LSD test; variable LOGHDD GENERAT Probabilities for Post Hoc lests MA}TOVA MAIN EFFECT: GROUP f 1Ì t?l t 4l {s} {6} GROUP r. /qJl-/b I .707508 I. i JIqlJ I t//-14 L . I ¿1!ö42 L.693907 IADY PELLY L. t1l 000000* 0537 3 0 03 5952 * 003060* 000000+ WISHBONE L. t21 000000* 000499* I5böI-L 0 08 559* 110 0 21 FERGUSON L. UJJ / JIJ 0004 99* 4 | / I 19 34't399 000029* l3l * HALOVIK L. 87 t4l 035952 J-5bör1 4L27 39 I 2 9950 Qt'? 652* HALOVIK L. 93 tsl 003060* 0 08559* J4 I 5YY 82 9950 0004 04 * KJTIGA L. t6l 000000* 1 10021 00002 9* ot1 652* 000404* MT. PELLY L 92 l7l 000000* Ig't 42L 0000 0 9* 02802t* Q00225* ort- / 5b '7 q5q?* MT. PELLY L 93 l8l 00 0 300* 039I'7 n1 I7 3404 060249 46501 4 ANDERS. B. L 93 tst 049352* 000000* 000334* 000923* 000007* 000000* ANDERS. B. L 94 t 10l 0487 64* 0067''Ì'7 * ttStöJ StJto¿ 6o2lL7 00034 6* CHAR L. t 11l 000000* ö þJO¡{Z 001-7 97 * 2021I0 021_ 4 3 3* 09 60 9L FISH TRAP L. l 12l 008 559* 5234r9 r52057 584006 3 I 0877 r.01190 STAT. LSD test; variable IOGHDÐ GENERÀ.L Probabilities for Post Hoc Tests MANOVA MAIN EFFECT: GROUP {7} {8i ¡ vt {10} t 11] t1)l GROUP I hvña I a 1.703189 r.tovtzS L.'7290'17 I. /UðþJ / L. t L4 t 6I LADY PELLY L. I1l 000 0 00* 0 00300* 04 93 52* 0487 64* 00000 0* 008 559* WISHBONE L. Í,2t L87 421 I UJYT I 000000* 006777* tt þ3042 J¿J4 TY * FERGUSON L. t3t 000009* 0 15592 00 0334* I t 3 té3 0 0l_7 97* 152057 HALOVIK L. 87 t4l 02802I* 1/J4U¿I 000923* JtJtþ¿ 2027t0 584 00 6 HALOVIK 1.93 t5l 000225* 060249 000007* 602tr7 02L433* 380877 KITIGA L. l6l brt- i 5b 4650'1 4 00 00 00* 00 034 6* 096091 r.0r.190 MT. PELLY 1.92 Í,7 1 683890 000000* 000285* L62212 LO¿A¿4 MT. PELLY L. 93 t81 68 38 90 000003* 036257 * 638250 ¡TJJ 05J ANDERS. B. L 93 te1 000000* 0000 03* 000507* 00000 0* 0 00 t-7 9* ANDERS. B. 1.94 l 10l 000285* 036257* 000507* 01 4300* 245980 cl-lAR L. l11l I622t2 o5ðz JU 000000* 014300* 5997 0s FISH TRAP L. t12) LO¿O¿4 000179* 245980 qqqTn c LADYPELLYLAKE HALOVI(LAI(E-(1987) FERGUSOIILAKE- ANDERSON. BAY LAKÉ(1993). MOUNT PELLy LAKE{1992). KTIGA-LAKE- HALOVIKT"AKE-{19e3) MOr.rNr PELU LAKE- ( I e93). oo FISH.TRAP LAKE- ANDERSON. BAY LAKÉ(.I 994) WISHBONEI-AKE CHAR LAI(Ë 1,4 12 108642 SQUARED MAHALANOBIS DISTANCE Figure 32. Adendrogram of Squared Mahalanobis Distances showing morphological relationships among the samples of Arctic char spawners examined. Table 14. A comparison ol-Squared Mahalanobís Dístances among the tr,vélve samples of Arctic chat' spawners examined across the sfudy area. STAT. Squared Mahalanobis Dlstances DISCRIM. ANATYSIS LADY L GROUP PELLY WISHBONE L FERGUSON L HALOVIK L 93 HALOVIK L 87 KITIGA L MT PELLY L 92 MT PELLY L 93 ANDER.B L 93 LADY PELLY L 0. 00000 1 6. 69256 17.28539 L4.2209L 10.05363 23 .27 652 I 6, 65691 2s.35519 L9.9'1432 WISHBONE L 16.69256 0.00000 tL.49273 2.88604 15.84033 4 .77 493 5 .57 4r7 5.59719 9 .60t25 FERGUSON L 1?.28539 LL .49273 o. 00000 12.32170 15. 8854 6 18.06606 18.0L483 13.00419 27 .O9344 HALOVIK L 93 L4.2209L 2. S8604 12.32L70 0.00000 Lr.29992 7 .77827 7.36378 1 1 , 55359 LI.tO2B'l HALOVIK L 87 10.05363 15.84033 1s. 8854 6 tr.29992 0.00000 L7 .72tL5 20.15940 20.83342 18.18811 KITIGA L 23.27 652 4 .77 493 18.06606 7 .77827 t7.72LI5 0.00000 rL .47294 LO.24306 L4.59668 MT PELLY L 9i I 6. 65691 5.57 4L7 18.01483 7.36378 20.15940 LL.47294 0.00000 7.03996 L2.I652L MT PELLY L 93 2s.3551.9 s.59?19 13.004r.9 11 .55359 20.83342 r0.24306 ?. o¡sge 0.00000 10. 50451 ANDER.B L 93 L9.97 432 9. 60125 27.09344 11.10287 18.18811 14 .59668 12.L652L 10.50451 0. 00000 ANDER.B L 94 15. 45816 3.0?086 16.61037 7.05201 20 . 64 503 11.67989 6. 3834 1 9.82706 9.51104 .Ø CHAR L 14.03767 1.83869 t2.22598 4.4L722 14.79436 9.807L2 5. 1 5338 6. 3 6813 9.27134 FISH TRAP L 23.56573 4.30436 10.93082 5.?1?99 14.80188 8.67531 8.79704 3.86582 to.07'110 STAT. Squared Mahalanobls Dlst,ances DISCRII,f . ÀNAI,YSIS GROUP ANDER.B L 94 CHAR L FISH TRAP L LADY PELLY L 15.45816 L4 .O37 67 23. s6s?3 WISHBONE L 3.07086 1.83869 4 .30436 FERGUSON L I 6 . 6103? 12.22598 10.93082 HALOVIK L 93 7.05201 4 .4L722 5.71799 HALOVIK L 87 20 . 64 503 14.79436 14.80188 KITIGA L 11.67989 9.80'tL2 8. 6?531 MT PELLY L 92 6. 3834 I s. 15338 8.79704 MT PELLY L 93 9.82106 6.36813 3. I 6582 ANDER.B L 93 9.51104 9.27L34 10.077?0 ANDER.B L 94 0.00000 2.15584 9.2826L CHAR L 2 . r.558 4 0.00000 4 .37555 FISH TRAP L 9.28261 4.3?555 0. 00000 86 Examinations of Upstream Migrations Cluster Analysis Cluster analysis was performed on samples of Arctic char from thirteen upstream migrations (Table 15). Samples from two commercial fisheries were also examined in this way. The latter samples were taken from gillnets set along shore in July and captured char as they moved along shore feeding. Cluster analysis begins by linking the most similar specimens and proceeds in a stepwise fashion, linking the next most similar cases until all specimens have been linked. Linkage distance (Euclidean in this case) provides a measure of similarity/dissimilarity of specimens and groups of specimens. The shorter the linkage distance, the more similar are the specimens and the greater the linkage distance between gïoups of specimens, the greater the dissimilarity of those groups. None of the specimens were identical with respect to morphometric measurements so all were considered as individuals in the first step. As the steps proceed, individuals that are similar to one another are grouped together and so on. All samples will contain a certain amount of intra-group variation and this will be reflected in various clusters formed during the analysis. I was interested in examining these samples for evidence of group structure similar to that seen in the discriminant function analysis of spawners. Therefore, in order to establish a linkage distance that reflected inter-group rather than intra-group variation, I examined two known groups of spawners by this method. I used the samples of spa\ilners from Lady Pelly Lake and Ferguson Lake that were clearly different from one another with respect to morphometric measurements (Fig. 15). The cluster analysis of these two groups (Fig.33) shows the separation of an apparent outlier (A) from the main 87 Table 15. Location and year of upstream migration of Arctic char examined by cluster analysis. Location Year Ekalluk River 1988 Ekalluk River 1990 Ekalluk River 1991 Ekalluk River r992 Ekalluk River 1993 Ekalluk River r994 Halovik River 1992 Lauchlan River 1992 Lauchlan River r996* Paliryuak River t992* Freshwater Creek 1 988 Freshwater Creek 199r Freshwater Creek r994 Jayco River 1990 Ellice River 1990 *Commercial fishery along shore LADY PELLY LAKE SPAWNERS AND FERGUSON LAKE SPAWNERS Unweighted pair-group average Euclidean distances TWO KNOWN GROUPS co cð FhfþOæhOqqÞñdfNÈddqlqæ6tÞF6tOþO9tsh6ñóþ-hd-hæôçh6þ6ÞFtón6Nñoôh+è6+ñoøoóÉÈdNF6aaæÈ{ÈêhOóffæÞÉ Oñfñflla rþ€æ€ræþ€þFEñFFFþ9h9tt6óh!6FFþhÉ9hFFþhhF@F thn60666@óhóñh É66N@ó-óêôóOê@Oñ6ó6060 rÐr€FtOOæqó6qOrr Or t ÉÉÉ--r-È çnn +t{hrhhtt ç+ñnhhhhhshh+ñhThth thçtç tt6nn ç çhç tt tgnv h î¡N NNNN C¡N NN NNN CIN NNdNNNNNNNNNNNNN NNNNdNNN NNNNdohh6S 66No ñ4666h 6hhnñn hñh6onhn6h ñh hñ hh ôh h h bn ñSnh 6 nah .I !! !I ! 9 É9 ! qV!! VI !? q!ç! Vq !V ç9 çç9IççIççç!ççT çNNNNNCINTNNNNNNNdNNNdNNNNdNNdNNNNôINddNNNNNNNNNC¡NNNNN 'T FERGUSONLAKE LADYPELLYLAKE Figure 33. Cluster analysis of morphometric measurements from two known groups of spawners (Ferguson Lake and Lady Pelly Lake). Sample identification numbers along abscissa. 89 group (B) at a distance of about 7.2. Group B appears to separate into Groups C and D at a distance of about 6.6. Group D separates into groups E and F at a distance of about 5.g. Group E comprises most of the specimens from Ferguson Lake and Group F comprises all but 2 of the specimens from Lady Pelly Lake. I repeated this comparison with nine other pairs of known spawners from across the study area. Group separation was reached at an Euclidean distance of between 5 and 6 in all cases. I then used this range as a decision-making guide to decide whether group separation in samples of upstream migrants was likely due to inter- or intra-group variation. The cluster analysis of the 1988 upstream migration of Arctic char in the Ekalluk River reveals a distinct separation of two specimens at cluster A from the remainder of the cluster B at a distance greater than 8 (Fig. 3a). Cluster B separates into Cluster C and D at a distance of about 6.5 . Cluster D separates into Clusters E and F at a distance of about 5.7. A further separation of cluster E into clusters G and H occurs at a distance of about 5.5. A conservative interpretation is to consider that Group D represents group structure. Cluster D comprises the majority of the sample. On this basis, a DFA with this sample as one group, and the samples of Ekalluk River spawners from Lady pelly, Ferguson and V/ishbone lakes was carried out (Fig. 35). The 1988 upstream migrants appear as a separate group. Chi-square tests with successive roots removed (0,1 ,2) were signif,rcant (p < 0.001). Variables contributing most to the discrimination were orbital length (OOL), gill raker length (GRL) and maxillary width (MXSD in thar order (Table 16). The Ekalluk River 1988 nonspawners appear to have longer gill rakers (Fig 36a) and a shorter maxillary width (Fig 36b) than the three groups of spawners. They appear to Linkage Distance UJ S !,ì 27366 27345 27357 'H 273& .=' UV 27324 õF o 27362 u) 27323 È 27349 q no.c O 27356 27352 ËEEI*v-ê 27347 tsE S E o I.ä s¡ 27348 qÞãB 27365 m ^ã.Ð-F¡- s'< 27363 Ë= ã'yi g. x U)¡rÞ(,) 27371 r ot^rñù.4 eLH'ö 27330 t- {x:.3 27353 c \'A9JHA Ê. P v 27340 c^ --'êJ'-+9 õ 27360 ?Ð Þ)i+-YøE F 27361 fr3 Io Þi¡H\Y 27358 ^r ê'-="'Æ.ñ Ð (D:+=E' 27337 gõ'c ¡.(D ts (l 27342 oo. 4-r^*ã:ts 27338 fDE Cñ ã. -.' H 27335 iq)-{ :' Ë c)=hôo --:a E 27344 I '4) ÊlP aQ 27339 )j Ë g v-¿^x.x 27343 äE ¡J lT1 Ø Ð gË Ë : õ'a' 27328 ¿IJJO ã; P.ÈV''H Y -!l- 27368 Ø6a gvr¡{X o. =. 'Þ '1J a ci 27332 el 9 ö Ê. 27331 ,Ei 9ra¿"^VJH^ 5 s;9.o 27372 o= sc :¿- o. it 27346 o so< I P z Fe E i. 27370 J. i'"d T : 27350 CO äãäF æ i-caH(D Lt555 æ ã+g\oIil - 2735r oi oo 27367 oIAæ 27327 27369 27329 27325 27355 27354 27326 27359 27341 27334 zl Jz¿ 06 o oaa o ß a^Å^ ø ^ ^ ooSo^;%obo"o.J$"oo ^a aa^^^1frl c\¡ ;o , .u a ]^ l*l o og o o o goo" i a É. :#-# a o ++ -:;ï#"i-ö",o^oo -1 rJ + O_ a * flüFoï*n -2 't¡' +i'* Ho*ËE" a + '-E+ tr tr tr -3 ++ Ë tr -4 -5 -8 -6 -4 -2 0 2 4 6 B Root 1 Figure 35. Discriminant function analysis of morphometric measurements of Arctic char from three spawning aggregations (Lady Pelly, V/ishbone and Ferguson lakes) and the sample of nonspawning Arctic char from the 1988 upstream migration in the Ekalluk River. 92 Table 16. Summary of the discriminant function analysis of morphometric measurements of Arctic char from three spawning aggregations in the Ekalluk River system (Lady Peliy, V/ishbone and Ferguson lakes) and a sample of nonspawning Arctic char from the 1988 upstream migration in the Ekalluk River. STAT. Discriminant Function .Ana1ysis Summary DÏSCRTM. Step 13, N of vars in model: 13; Grouping: GROUP (4 grps) .ANAI,YSIS lViLks' Lambda: .022]-7 ìlpprúx. F' (39¡566):f6.040 r:r<0.0000 V{iIks' Partial- F-remove l-lô|êr / r\-¿ u Lambda Lambda /? 101L¿!t \ /Þ-Qn¡ \ \rt p-1evel Toler. \¡\ v\a¡. / LOG]\IXW . UJJJSY .6d49û0 32.087tJ4 . 000000 83709S r629Õ2 LOGOOL .039466 .3þI þöZ 49 .68328 .000000 857 991 r42003 n ?.4 qn.? .642489 ?5 ¿2?nO .000000 I9-? 044 1.nÁqq6 !vuru! . u¿ozó ! .843482 LI.81"407 .000000 oYvtSl 3 00243 !vg.ru .026196 . Õ40¿¿r .000001_ '778523 281477 !uuur! . vzoJ43 . 1'l oo?ol õ4I4JJ .000000 7 84229 ¿IJI II LOGBDD . U¿O3ZI . öJÞöZ ö 12 . 5052 I .000000 o¿Jo¿¿- Jt4Jtó !vuur- ÕaEaa ^ l-J..lUJ-LJ .000000 c^âtroô 1931L2 LOGANL .025617 .865338 o on?"1 .000004 320664 LOGLUL . v¿o¿5L . 84507 6 J_r-.o/_LÞy .000000 657 87 9 342L2I LOGTTL . U¿JY45 .854445 10.84560 .000001 6L4433 3 I 5567 LOGDOL .025302 o nn"^2 .876110 .000013 61 8028 sZLY | ¿ LOGTOW . uz4¿vv . vr5b4ö I Xh5 | | .000750 5 /¿154b 4Z5454 93 -Tr-l"l_.T-., J tt-l- ú. l¡-l J U.Èt Lll"ll. I lttll'lllll 0.7 :r_l_T I tl.96rStd.Dev. cl El t1.00'Std. Dev. u.o o Mean 1.06 1.00 l-T 0.94 l"llt"ltl B o.ae oã Jo 0.82 I lr.rt-r u./Þ Ï _l_ I t1.96*Std.Dev. b l-l È1.00'Std. Dev. 0.70 tr Mean 1.28 1.24 1.16 J ..tz o8 J, 1.08 1.04 1.00 lf t1.96'Std.Dev. t Ef t1.00'Std. Dev. 0.96 tr Meân *"r!51.t.. wsHB4oNE L. FERGUSoN L. EI(ALLUKR. Figure 36. A comparison of mean log (a) gill raker length (GRL), @) mæriilary \ ¡idttt G\ßU/), and (c) orbital length (OOL) among samples from three spawning aggregations in the Ekalluk River system (I-ady Pelly, Wishbone and Ferguson lakes) and the sample of nonspawning Arctic char from the 1988 upsüeam migration in the Ekalluk River. 94 have a small orbital length, similar to the spa\ilners from Ferguson Lake (Fig 36c). A comparison of maxillary width and gill raker length between samples is shown in Fig. 37. The sample from the 1990 Ekalluk River upstream migration appears to be comprised of one main group (Fig. 38), cluster G, separated from a number of individuals at a distance of about 5.7. Further separation at a distance less than this could represent intra- rather than inter-group variation. Cluster G comprises the majority of specimens in the sample therefore it was included in a DFA with the three groups of Ekalluk River spawners (Fig. 39). The Ekalluk River 1990 upstream migrants appear to be most similar to the spawners from Wishbone Lake. The cluster analysis of the sample from the 1991 Ekalluk River upstream migration reveals a number of possible outliers and one main group separated at a distance of about 5.8 (Fig. 40). Group F comprises the majority of specimens in the sample. It was therefore compared with the samples from the Ekatluk River spawning aggregations from Ferguson, Lady Pelly and Wishbone lakes by DFA (Fig. al). The 1991 Ekalluk River upstream migrants appear to be similar to the Wishbone Lake spawners. Cluster analysis of the sample from the 1992 Ekalluk River upstream migration appears to be quite heterogeneous and separates into six clusters at a distance of 5.2 or. greater (Fig. aÐ. Cluster J appears to be the main cluster with clusters C, F, I, H and B as outliers. Cluster separation at a distance less than this is likely to represent intra-group variation. Therefore, I did not consider cluster separation at a distance less than this as representative of group structure for that reason. This sample was then compared with the three Ekalluk River spawning aggregations that were taken in Lady Pelly, Wishbone and 1.15 1.00 0.85 .ro o d g,.o T ä se 'Bt.*$fu; o 1-- 0.70 #m" zo IU 0.55 É 0.72 0.80 0.88 0.96 1.04 0.72 0.80 0.88 0.96 1.04 I.Il V LADY PELLY L. WISHBONE L. E 1.15 J õ 1.00 O o ooo^ oo o }r.ei:d#". r o 0.85 o "** oo o "Js6"sry. 0.70 "3 Boo 0.55 0.72 0.80 0.88 0.96 1.04 0.72 0.80 0.BB 0.96 1.04 FERGUSON L. EKALLUK R. 1988 LOG MAXILLARY WIDTH Figure 37. Aplot of log maxillary width (MXSD against log gill raker length (GRL) for Arctic char spawners from three spawningaggregations in the Ekalluk River system (Lady Pelly, wishbone and Ferguson lakes) and the sample of nonspawning Arctic char from the 1988 upstream migration in the Ekalluk River. EKALLUK RIVER UPSTREAM MIGRATION 1990 Unweighted pair-group average Euclidean distances 6.5 6.0 5.5 5.0 o 4.5 oc ((t 4.0 o'.9 o 3.5 oo) l¿ jjc 3.0 2.5 z.o 1,5 cltt¡or\otr|$0o1r¡Þ-ôl$ìr|1"l or\f,0oÌ\11 ooÊHo\t-rÛÌ\oo\ortoN¡€\oô¡\oorôr-.oiôe.¡oÈ\oor.|1ôdoo\ c\¡()C'lc.|cQ(f| clc.ìFH(\dHQHOO(\lC.l(1 C)Oro\O\tlÉdOOrclôlOtOrO\cìdOôlcf¡clOÉaOôlOrOrOrOoo C.¡C.lCìC.lC.,¡C{Cìc.lC.lô¡C.¡c.¡NNNôlNCilCilC.lC.lÊHdC{C.lCr¡C.ldC.¡C..lÈdÈNC.lCìe.¡Cilc.le{.C.¡clc.¡c.ldFdc¡É tî G'ì Cô C.¡ Cl îô CA tî Cî Cô Câ Cî Cî 1ô (r¡ CA CA 11 (ft Cî tî ffl CO tî C.t Cl Cô (.t C.¡ Cl C"t Cl tA tô C.r Cf¡ C1 C.t Cñ Cî C.¡ Cî Cr| C.t Cî Ca CA C1 C1 tA cat.¡tacn11tñalcfitf¡cîtñtîcaîa(atîcf¡tîtô(1tîcît¡(n11ta(r¡t.¡(acamtlm(1c1c.¡c1mcîcatîcîmcîtococ.¡cacôca Figure 38. Cluster analysis of morphometric measurements of Arctic char from the 1990 upstream migration in the Ekalluk River. Cluster G is considered to représent ' a group in this analysis. Sample identification number along abscissa. I O LADY PELLY L. I I tr WTSHBONE L. | Ä FERGUSON L. | + EKALLUK R. 1sr9o aÁ, ,6\ ãA a ^î^j*\ä -o f^ , À lä:^uro * $o aRÂ-ff8*+ oo o o + o P."*^ . Ë$Ëm:h- o %'îo% to å. + \¡ €";,t* drn Étrt " tl+ +*+ :ód tr --s oÈËåþJ1.. o u % Jo";"; ++ "6-4-2024 Root 1 Figure 39. Discriminatrt function analysis of morphometric measurements of Arctic char from three spawning aggregations in the Ekalluk River system (Lady Pelly, Wishbone and Ferguson lakes) and the sample of nonspawning Arctic char from the 1990 upstream migration in the Ekalluk River. 5+ZJ t 34239 F 34236 0q 34207 õr¿. ?^r)) è 34224 ìo 3419s 34192 *-l,-l trt - 34220 m tÐ Edi,DE3ä 34196 ÞH¡r 34191 34212 (f ø) 34203 m arF-/. ^Ë' 86 O LADYPEL E WISI{BONIE L. A FERGUSON L. o + +'p+n trEl + + EKALLUK OO @ oo + o ;*furo;f: .gT"" o o + oo"& oo å ,"13 *4n ooo +* ïTo^nn ,Þ".' *^*o 4L  *Ï* f, 'À Å oh^* A 2 Root 1 Figure 41. Discriminant function analysis of morphometric measurements of Arctic char from three spawning aggregations in the Ekalluk River system (Lady Pelly, Wishbone and Ferguson lakes) and the sample of nonspawning Arctic char from the 1991 upstream migration in the Ekalluk River. Linkage Distance (¡) Þ À -È, 'O gr 'O .1.,r 35749 35742 35781 ñ' 35766 o 357& è 35758 I.) 35778 35751 acgOr-t Ft (-ê(,- 35782 Ëã6' 3s756 35783 il il Ê) 35786 H.9H m câ 35785 ç¡ YT='(< 9. 35754 -^ ÞÞøl 3s753 r 001 101 Ferguson lakes by DFA (Fig. 43).It appears to be most similar to the sample from Wishbone Lake, but group centroids differ. Cluster analysis of the sample from the Ekalluk River 1993 upstream migration reveals a number of individuals or pairs that separate from a main group at a distance of about 5.8 (Fig. 44). Cluster A, C and E appear to be distinct from cluster F, which comprises the majority of the sample. This sample was then compared with the spawners from Lady Pelly, Ferguson and Wishbone lakes by DFA (Fig. a5). The results indicate that the Ekalluk River 1993 sample is most similar in morphology to that from V/ishbone Lake, although a small number of specimens appear to resemble those from Ferguson Lake. The sample from the 1994 upstream migration in the Ekalluk River appears to be comprised of one main group and a number of outliers as shown by the cluster analysis (Fig. a6). Cluster F separates from clusters A, C, and E at distances greater than 6.5. Further separation of cluster F takes place at a distance of about 5.3. This distance is close to the lower level observed in the separation of groups of known spawners, therefore, cluster F was considered to be representative of group structure. It comprises most of the sample and was compared with the spawning aggregations from Lady Pelly, Ferguson and Wishbone lakes by DFA (Fig. aD. In the discriminant function analysis, the sample from the 1994 Ekalluk River upstream migration appears to be a distinct group, but appears to be most similar to the sample from'Wishbone Lake. A summary of the DFA analysis is presented in Table 17. AII Chi-square values for successive roots removed (0,I,2) were significant þ < 0.001). Morphometric measurements that O LADY PEI-LY L. tr WISI-IBONE L. Â, FERGUSON L. A + EKALLUKR.1992 åaS a. åù' f ^a a dêA A^ .r Ef å^^^ uo u ÂÏt**åo-t;T" o tr C\¡ o : E o a ¡' ã o () g ^ * a"o"qroo q. .'o o.. E_,# '* M -o * ,FH H; ++ NJ o T"{S.S'- ;"*".& +Ð-"1: {: ,+ o d. Fî'. +* o + ++ .r- + -6 -4 -2 Root 1 Figure 43. Discriminant function analysis of morphometric measurements of Arctic char from three spawning aggregations in the Ekalluk River system (Lady Pelly, Wishbone and Ferguson lakes) and the sample of nonspawning Arctic char from the 1992 upstream migration in the Ekalluk River. Linkage Distance 37786 37790 .H 37762 Ë' 37776 H .Fl 37779 (D. è 37750 È 37772 oecO 37766 - :3äHHr;-v-2 37761 €ã6. 37773 .Þilp¡ 37792 FH^T+Ð 37759 ¿ ¿ P F.9- m (rt. ^:'(< 37768 pYi 9. 37767 i{ .Þ Þ c,ì PL.A 37760 Uts^v 9 H. r lâi)A 37763 r a^F.t' C v¿H^ 377& rn'+ 5 C^ x.- 5 t¿ 37757 3-n 5 gä 37785 i- b.a 37774 37756 EE ñ 37788 '9XË F,i (Ì 37769' *gç h.4. F'ly ^r 37783 qE g ,,ã'á E ¿+ .' Ft 37781 Í1':o 377E7 ¿Þ'o $ g ; É.(D-.P 37765 äE Ëäã 37782 EË 8'"J;tt 37754 ãECNõQ : ä'P 37752 37793 t=F ve'd. ¡.¡. E.P O 37789 ,Ef uY. li. er ìË -{ 37758 o sÊã^ 37791 !¿2^4 X H. z s'Þ 37770 J ã' (O F ã+ 37755 (o 377tø- (, Htsã(D 377sl 'oHro \o 6r*, 37771 37747 37175 37780 37746 37777 37749 37748 37745 37778 37744 EOI LADY PELLY L. I WISIIBONE L. I FERGUSON L. I EKALLUK R. 1993 I a '+ ^l/t t ^ ^ a C\¡ 2 . Ttê ^ ^^^^ ++ *hri*l a o &1 + l+J,ç_b^ o od^€ ^çPFgg" oo ffi"Bo- À ondo *o o + o ;#*Fj+ ooo do Ë" tr ooo tr -5 -8 B 10 Root 1 Figure 45. Discfiminant function analysis of morphometric measurements of Arctic char from th¡ee spawning aggregations in the Ekalluk River system (Lady Pelly, Wishbone and Ferguson lakes) and the sample of nonspawning Arctic char from the 1993 upstream migration in the Ekalluk River. EKALLUK RIVER UPSTREAM MIGRATION 1994 Unweighted pair-group average Euclidean distances A B D F (r¡ ql)È rt (o (o o)$ co¡f, (ot o ç\¡o c{ ct, c{cOl> O¡ oÇt rA q9 Þ SqlO ( {¡ Q¡ rA(Ð Irr¡> qr!g A ç? r Q --E çr (! @ !'- ç! oì ö õ õ cö ñ ñ ñ ñ F ö õ qi õ, ñ õ ¡o ö Ñ Ñ ¡- õ õ ô ó õ õ ö ö o, O Ñ A Q ó @ co F € e e tq I Figure 46. Cluster analysis of morphometric measurements of Arctic char from the 1994 upstream migration in the Ekalluk River. Cluster F is considered to represent a group in this analysis. Sample identification number along abscissa. A aaA ara i^ la^ a ^ ^ A ^AA * o ^^ ^^^^$þn¿Ëru a oo A ¡ ooo E + t* o tr tr ^EB J +{'+ tîs gf_ogq_ trdt*++ ootr¡J qP*' Ë* f Jts {+ " oç- oo=Eo" + "*qud*"eBo þo H, l....j+ oovl trù'l+ ++ o trF+J+ o .6-4-2024 Root 1 Figure 47. Discriminant function analysis of morphometric measurements of Arctic char from three spawning aggregations in the Ekalluk River system (Lady Pelly, V/ishbone and Ferguson lakes) and the sample of nonspawning Arctic char from the 1994 upstream migration in the Ekalluk River. t01 Table 17. Summary of the discriminant function analysis of morphometric measurements of Arctic char from tbree spawning aggregations in the Ekalluk River system (Lady Pelly, Wishbone and Ferguson lakes) and a sample of nonspawning Arctic char from the 1994 upstream migration in the Ekalluk River. STAT. Discriminant Eunction .Analysis Summary DISCRÏM. Step 10, N of vars in model: 10; Grouping: GROUP (4 grps) AIüA],YSiS Wiìks' L¿rnbda : .A2682 approx. F (30,564):45.7i9 p<0.0000 Wilks I Partial F-remove 1-Toler. 'l I\:Z U J l,ambda Lambda (3, r92) n- or¡a I Tol-er. LOGOOL 058 04 0 4 6213 0 14 48e27 0.000000 I 55914 144086 LOG}4(W 0423L8 OJJ ðZ ð 97374 .000000 to¿t tJ 237227 LOGPCL 0-?6465 007 e2 .000000 þ5 i J1r Jet þð v LOGLAT 036808 7287 08 23 UZ Oþ4 .000000 581636 4L8364 LOGBDD 03 758 5 713650 25 6't982 .000000 533042 ¿{ ooyJö LOGANL 030846 ðb:r5b1 60038 .000006 I I ¿t I Or 225239 LOGHÐÐ 03 002 6 I 932 98 oqqb5 .000075 54 94 00 450 600 ô^1 C LOGCFI vLJWa2 Y¿JJ49 J L¿O J . vvrJf ' v^ 90l_ 973 vJovz I 1 LOGTOW 029772 90093 6 VJIZO .000163 47 3L7 4 526826 LOGID(Ï, 029372 YI-JIö b 6 0842'l .000563 40t267 108 contributed to this discrimination of the four groups were orbital length (OOL), maxillary width (MXW), and pectoral fin length (PCL) in that order. The sample from the Ekalluk River 1994 upstream migration had relatively short pectoral fin length (Fig. 48a) and narrow maxillary width (Fig. a8b) compared with the spawning aggregations. They had a small orbital length (Fig. 48c), similar to those in the sample of spawners from Ferguson Lake. The relationship of maxillary width and pectoral fin length for each group is shown in Fig. 49. A discriminant function analysis of the three spawning aggregations frorn the Ekalluk River (Lady Pelly, Wishbone, Ferguson lakes) and the two distinct groups of upstream migrants observed in the 1988 and 1994 samples reveals discrimination among all five groups (Fig. 50). The summary of this DFA is presented in Table 1S. All Chi- square values with successive roots removed (0,1,2,3) were signifîcant þ < 0.001). The variables that contributed most to this discrimination were orbital length (OOL), gill raker length (GRL) and maxillary width (MXUD in that order. The samples from the 1988 and i994 upstream migrations had a small orbital length similar to the Ferguson Lake sample (Fig. 51a). The sample from the Ekalluk River 1988 upstream migration was distinguished from the other four samples by a relatively long gitl raker length (Fig. 5ib). The samples from the 1988 and 1994 upstream migrations had a narïow maxillary width, similar to those from Wishbone Lake (Fig. 51c). The relationship between maxillary width and gill raker length for these five groups is shown in Fig. 52. A discriminant function analysis including the six Ekalluk River upstream runs, the three spawning aggregations from the Ekalluk River system (Ferguson, Lady Pelly, 109 2.O0 -i- -j- T 1.96 nl" lt-lT l'lLJl"l I J I r.gz o t---J-lllt+ 9 1.88 -ü 't.u IL t1.96'Std.Dev. - a E tt.oo'std. Dev. 't.80 I _Mean_ 1.05 1.00 0.90 3 o.æ (,Ë q - 0.80 0.75 It 0.70 lf t1.96'Std.Dev. b tll tt.ofstd. Dev. 0.65 'o Mean 1.28 122 1.16 oJ 9 r.ro 1.04 lI t1.96'Std.Dev. c 11 t1.OO'Stcl. Dev. L80 o 'Mean LÂDYPELLYL TI'ISHBONEL FERGT'SON L EKALLUKR. ts87 19s.. 19S 1994 Figure 48. A comparison of mean log (a) pectoral fin length (PCL), (b) mædllary \¡¡idth (ND(W), and (c) orbital length (OOL) amotrg sâmples fromthree spawning aggregations in the Ekalluk River system (Lady Pelly, Wishbone and Ferguson lakes) and the sample of nonspawning Arctic char from the 1994 upstream migration in the Ekalluk River. 2_06 oo^ a o o 2.00 oo o ood "ffi"" o .hkå"" 1.94 o o B Jgo* F- (t 1.88 z ti-l 1.82 z 0.68 0.74 0.80 0.86 0.92 0.98 1.04 0.68 0.74 0.80 0.86 0.92 0.98 1.04 U- LADY PELLY L. WISHBONE L. É 2.06 C) þ- c) 2.00 % LJ-l o OO o- 8o9( o o o o od o,þ o 1.94 bo fffig(@ ÐB o %oo b BB"o *3" 1.88 %ooå;";?; 1.82 0.68 o]4 0.80 0.86 o.sz 0.98 1.04 0.68 0.74 0.80 0.86 0.92 0.98 1.04 FERGUSON L. EI(ALLUK R. 1994 LOG MAXILLARY WIDTH Figure- 49. Aplot of log maxillary width (MX\Ð against log pectoral fin length (PCL) for Arctic char spawners from three spawning aggregations in the Ekalluk River system (Lady Pelly, Wishbone and Ferguson lakes) and the sample of nonspawning Arctic char from the 1994 upstream migration in the Ekalluk River. o LADY PELLY L. 5 tr WISHBONE L. A FERGUSON L. A ¡ EKALLUK R. 19BB a tr + EKALLUK: R. 1994 A A al^^^^ tr¡\o^ot + ru ^ {;q,r^.^{T" *Ê* + A ^ c{ oa ^^o o u . o o^o ^ Ëå* - *+..r Ji,,. M. o o...,o "ÏH..{""ff=o r% É** o- ooooo 4 ,- oË o þo^8&o _:^.ro Ëî"J-ur i****'ir.r -?. oBoo ,=*rl"r.t. ^ o o +- o- oo o -3 o n"gt ¡l -4 -5 -8 -6 -4 -2 4 6 Root 1 Figure 50. Discriminant function analysis of morphometric measurements of Arctic char from three spawning aggregations in the Ekalluk River system (Lady Pelly, Wishbone and Ferguson lakes) and the samples of nonspawning Arctic char from the 1988 and 1994 upstream migrations in the Ekalluk River. t12 Table 18. Summary of the discriminant function analysis of morphometric measurements of Arctic cha¡ from three spawning aggregations in the Ekalluk River system (Lady Pelly, Wishbone and Ferguson lakes)'and samples of nonspawning Arctic char from the 1988 and 1994 upstream migrations in the Ekaltuk River. ST.A.T. ÐiscrimÍnant Function Aaalysis Summary DTSCRÏM. Step 1-3, N of vars in model: 13; Grouping: GROUP (5 grps) .Aì.ïAIYSiS 'rtil-ks' Lanbda: .01838 approx. F (52,927)=32 . ¿¿J p<-v. uuuu Wil-ks I Partial F-remove 1-ToLer. /Þ-(ar I N:256 Lambda Lambda (4,239) p-IeveI Toler. \t\ vY!. / LOGïD(W 0254 0 1 I ¿JJCY 22.82907 000 00 0 800304 199'69 6 LOGOOL 03311 0 5550 I 0 47 .892t'l 0 0000 0 ÞcvIcz 140848 LOGGRL 0-?2230 51 0242 45.0_?006 n nn nnn 907 92 0 092 08 0 LOGPCL 022420 8197 48 I-J.IJöZJ 000000 598491 4 01 503 I.OGANL 02 1 905 83902 3 11.46380 0 0000 0 7503 94 249606 LOGLAL 02325r 1 90452 LJ.ó5962 000000 601 490 5V¿Ð IV LOGBDD 02347 9 Ió¿IÐO l_o. Jðzör 000000 4]-0439 LOGHDÐ 02L026 O B 6C595 'AIUA . 0c00 02 536418 163582 LOGCPD 0207 40 886138 1 .6'7'7 44 00 000 I 504 907 4 95093 LOG¡D(L o2021,'l 90907 2 00 0l_34 ¿¡I-JJIö 5e4682 LOGIOlT 020471 89'7196 6.801_89 000034 49t466 50 853 4 LOGLU], 019956 92 0 958 5.L281,t 000557 IvJOtZ 206328 LOGCP¡ 0 1 9793 YZö55J 4.5y | 43 001 35 6 ö bbv-L u r5.5VóZ 113 1.24 à 120 l"l -r 1.16 i. j.r- J :r 1.12 o8 I "l-l_ [lrl 9 r.æ 1Èl"lL:l.l 1.U IL ¡^ g -T- 11.96'Std. Dev. u.t o Ef t1.ocStd. Dev. o Mean 1.1 0.9 J 9 0.8 0.7 lI t1.96'St Figure 51. A comparison of mean log (a) orbital length (OOL), (b) $11 raker length (GRL), and (c) mærillary \¡/idth (t\Ðffi) among samPles from three spawning aggregations in the Ekalluk River system (Lady Pelly, Wishbone and Ferguson lakes) and the samples of nonspawning Arctic char from the 1988 and t994 upsteam migration in the Ekalluk River. 1.15 1.00 o oa^oo o 0.85 {dffi' ,.ffi. "#& t-'- 0.70 f oz Bo, UJ 0.55 & 0.68 0.74 0.80 0.{}6 0.92 0.98 1.04 0.68 0.74 0.80 0.86 0.92 0.98 1.04 0.68 0.74 0.80 0.86 0.92 0.98 1.04 IU V LADY PELLY L. WISI{BONE L. FERGUSON L. 1.15 M (, 1.00 è C' C) 0.85 .ffioo do ^% 0.70 }r:"ffi; o 0.55 0.6ft 0.74 0.80 0.86 0.92 0.98 1.04 0.68 0.74 0.80 0.86 0.92 0.98 1.0rt EKALLUK R. 1988 EKALLUK R. f994 LOG MAXILLARY WIDTH Figure- 52. Aplot of log maxillary width (MXW) against tog gill raker length (GRL) for Arctic char spawners from three spawning aggregations in the Ekalluk River system (Lady Pelly, Wishbone and Ferguson lakes) and the samples of nonspawning Arctic char from the 1988 and 1994 upstream migration in the Ekalluk River. 115 V/ishbone lakes), and the other spawners from the V/ellington Bay area (Halovik Lake 1987, Halovik Lake 1993 and Kitiga Lake) was caried out. A comparison of Squared Mahalanobis Distances indicates that all six samples of Ekalluk River upstream migrations are more similar to the samples of Ekatluk River spawners than to those from the other samples of spawners (Table 19). The Ekalluk River 1990, I99l and 1993 samples appear to be most similar to the Wishbone Lake spawners while the Ekalluk River 1988, 1992 and 1994 samples are more distant. There was a similarity between the Ekalluk River 1991 and 1993 samples of upstream migrants and spawners from Halovik Lake 1993. A cluster analysis of the upstream migration of Arctic char in the Halovik River in 1992 suggests that it was comprised almost entirely of one cluster (Fig 53). Outlier A separates from the remainder of the specimens at a distance of about i0.8. The pair represented by cluster C separate from cluster D at a distance of about 5.8. Further separation of cluster D occurs below 5.5, which could represent intra- r'ather than inter- group variation. Therefore, cluster D was considered as representative of group structure. This sample was compared with the samples of spawners from Halovik Lake 1987 and 1993 by DFA (Fig. 5a). The three samples appear to be distinct from one another in terms of morphometric measurements. A summary of the DFA is shown in Table 20. The variables that contributed most to the discrimination were body depth (BDD), caudal peduncle depth (CPD) and maxillary width (MXVD, in that order. All Chi-square values with successive roots removed (0,1) were significant þ < 0.00i). Halovik River 1987 spawners were characterized by small body depth (Fig. 55a), relative to the 1993 spawners and the 1992 upstream migrants. The Halovik River 1993 spawners ll6 Table 19. A comparison of Squared Mahalanobis Distances among samples of Arctic char spawners from the Ekalluk River system (Lady Pelly, Wìshbone and Ferguson lakes), Halovik Lake 1987 and 1993, and Kitiga Lake, and the six samples of nonspawning Arctic char from the upsheam migrations in the Ekalluk River (1988, 1990,1991,1992,1993 and lgg4). STAT. Squared MahaLanobis Distances n1 cap TM ÀIÌATYSÏS þ¡1UUr PELLY L WISHBONE -ADY L FERGUSON L HALOVIK L 87 HALOVIK L 93 KITIGA L CJ) 11 lr LADY PELLY L 0. 00000 6 r.093 t8 .7 4642 !L.VJ¿O¿ l-J 010 05 23.01470 .uJ WISHBONE L 1?.61093 0 00000 rr.. ¿J.yÞ5 .t.ö¿>éJ z -'18 L6.26840 2 3 FERGUSON L .7 4642 11 ¿ TJOJ 0.00000 17.65114 L¿ ¿rJró Lt. t¿J3L HALOVIK L 87 77.03262 IÞ 26840 I /. ÞÞtl.{t 0.00000 10 4924'l J. /. / /Ð5y (L yöõöl_ o HALOVIK L 93 13.01005 ¿ L¿ . ¿TJLó t0.49247 0 00000 /.þ/u5ö KITIGA L 23.01470 4 82983 17 .72597 t - / /-ì5V 670?n o onôon Ø R 88 33 . 3 6045 95907 ¿q . ¿rJ>J J{ . ÐÐyJI 17118 ¿ö.otLL¿ É. =KALLUK R 90 25.6L927 591 69 t4.09t22 ¿o. Jq I 59 11 t! =KALLUK 26628 rþ.cbzu/ z :KALLUK R 91 22 .48420 '7 52t0 t¿. t>vto 20.89145 49061 14.L9243 3 :IGLLUK R 92 26.r235L 10 2944I 21 .31739 22.83909 11 7q1 ?1 ¿Þ.Þy/l/ :KALLUK R 93 n o- 29.46458 0351 9 15.43286 03257 1 6. 941 64 Ø :} Ltl HALOVIK L. 1987 HALOVIK L. 1993 HALOVIK R. 1992 trtrtr ^lr trtr trEI t] q m tr E-trtrt ¡A f ÀA Hn _ftoo uE A¡ tr* trtrn -o trtr a c{ tr ta /A^ ^ õ0 tr uEE ârr44 o A !r r¡r M. nEtr é^^ 4 gtr n AA -! tr AAA A g oo o ooo -2 o oo o o ^ o -3 o À ¡, -¿l -5 Root 1 Figure 54. Discriminant functign analysis of morphometric measurements of Arctic char from spawning aggregations taken in Halovik Lake 1987 and Halovik Lake 1993 and a sample of nonspawning Arctic char from the 1992 upstream migration in the Halovik River. ll9 Table 20. Summary of the discriminant function analysis of morphometric measurements of Arctic char from spawning aggregations taken in Halovik Lake 1987 and 7993, and a sample of nonspawning Arctic char from the 1992 upstream migration in the Halovik River. STAT. Discriminant Function Änalysis Sunmary DTSCRIM. Step 5, N of vars in modeL: 5,' Grouping: GROUP (3 grps) -Aì'IÂ],YS i S w*ilks I Lanbda : . 1i 64 4 aÞÞTox . F (LO,22A):42.411. p<0.0000 I 9'liIks Partial- F-remove l- l ol-er . T -*Li- I I N=1 l- 7 !atuua La¡nbda (2, rto) n- o¡ro Toler. (R-Sqr. ) LO@,D(W I47 97 0 1 86932 14.89170 00ü002 828 675 171_325 LOGBDD 2]-8290 5334 3 0 48.t0629 000000 600 82 6 399r'7 4 LOGCPÐ I bU3J5 20.82635 00 00 00 q qqn? 6 440964 LOGCPL I Y¿5JY 74 .41296 0000 03 957 7 07 o42293  n 1^^a LOGHDD 12s1 50 YJUl¿Z .}.IL¿JI 018941 661 850 JJõI5U r20 2.16 2.12 208 r-à o I z.ø It|l rT :R | r zæ I l"l----T---- - 1.96 I -T- t1.96'Std. Dev. a E t1.00'Std.Dev. 1.92 tr Mean 1.64 1.6¿ 1.60 1.58 o 1.56 o P r.s¡ J fi 1.52 r.50 1.Æ IE t1.96'Std. Dev. b E t1.Ofstd. Dev. ' 1.46 r o Msan - r.06 1.00 T 0.94 l^l-T- 3 j o.ea +l-riioiT o lti I T rll 0.76 _:r Ï t1.96'Std. Dev. c Ef t1.00'Std. Dev. 0.70 El Mean HALOVIK L HALOVIK L. HALOVIK R 1987 1993 1992 Figtue 55. A comparison of mean log (a) body depth @DD), (b) caudal peduncle depth (CPD), and (c) mæ 1992 upstream migrants had a narrow maxillary width (Fig. 55c) relative to the two samples of spawners. The relationship between body depth and maxillary width for each group is shown in Fig. 56. The cluster analysis of the sample from the 1992 upstream migration of Arctic char into the Lauchlan River suggests that it was comprised almost entirely of one group, based on morphology (Fig. 57). With the exception of one outlier, A, that separated from cluster B at a distance of about 13.4, the rest of cluster B shows separation at a distance of 4.6 or less. Therefore, cluster B was considered to have comprised a single group. There were no spawners from this system with which to compare this sample. The cluster analysis of the sample of Arctic char from the commercial gillnet fishery at the Lauchlan River in July 1996 (Fig. 58) suggests that it was comprised primarily of one group, based on morphology. Specimens A, c, and F separate from cluster E at a distance of about 5.3 or greater. Further separation within cluster E occurs at a distance ofabout 5 or less. Therefore, cluster E is considered representative ofa group. The sample of Arctic char taken in the commerciat gillnet fishery at Paliryuak River in July 1992 appearc to be comprised of one main group and a number of outliers (Fig. 59). Cluster L comprises about 70 percent of the sample. The other specimens separate from this group at a distance of about 5.3 or greater. Further separation of cluster L into two groups occurs at a distance of about 5.1. However, this separation could represent intra- rather than inter-group separation. There were no samples of spawners from this system with which to compare this sample. 1.10 1.05 oo o 1.00 o o 0.95 oo o% 0.90 ooo j'dffi.# o 0.85 0.80 o t-l: 0.75 c) 0.70 ;3 0.65 1.94 1.98 2.O2 2.06 2.10 2.14 2.18 1.94 1.98 2.02 2.06 2.10 2.14 2.18 É. HALOVIK L. 1987 HALOVIK L. 1993 1.10 1.05 E 1.00 N) (, 0.95 NJ o 0.90 0.85 0.80 .'å,.þ.f o o.75 0.70 o 0.65 1.94 1.98 2.02 2.06 2.10 2.14 2j8 HALOVIK R. 1992 LOG BODY DEPTH Figure 56. A plot of log body depth (BDD) against log maxillary width (MXW) for Arctic char spawners from Halovik Lake 1987 and Halovik Lake 1993 and a sample of nonspawning Arctic char from the 1992 upstream migration in the Halovik River. LAUCHI-AN RIVER UPSTREAM MIGRATION 1992 Unweighted pair-group average Euclidean distances 14 l2 l0 gB'o) o .9, o Ut.) oo o) (I' .Y 54 2 o ñün3**HxHHnHR*snä6ñHEHãËäBBä88È$ät8ä8$8ää8sä8ä6EEË68h8ãË$.r.rr.f.+.+\r.rsr(fs$.+\ftûrtlfltisSt-+++i:fÍ-iiilîîifËlfË$:tîl Figure 57. Cluster analysis of morphometric measurements of Arctic char from the 1992 upstream migration in the Lauchlan River. Cluster B is considered to represent a group in this anaþsis. Sample identification number along abscissa. 427t5 -r> 42120 o 427t4 42100 42101 42099 qrl o- (Jt 42097 90 42t12 42108 ctt X l-i |1Þø: 42741 ¡;Eõ' 42139 oo'- 42131 tsxP 42t40 0a- < 42142 ã u,:. g. 42126 êrvr 'F5a:-(DÉ. 42t18 câ*|J 42t06 42121 c H;iYP ä.N :f 'd oc 42t35 m Ér o.4 õ 42107 42138 11]3'È e;E 42t24 F=o Ê ã i-.i. - 42133 =oO.O-r R['3 42t05 gE z o3.È låã tí 42737 42t43 o-,I Ð !JHdJ 42123 ßÞ 42129 ñ F- l-. )i n EEã 42r27 oor.ãõ S) *.O 42111 (Í, 42736 o(o Ð =r 42t28 (oõo) ark å 42lro ï, o I Po 42116 ø'õ Ë 42r25 42109 ts-( 42103 u)à (!+ 42117 42732 H(D 42130 o 42144 r¿ 42119 42098 42134 42122 42104 42113 42102 42096 42095 Þzl PALIRYUAK RIVER COMMERCIAL FISHERY. JULY 1992 Unwe¡ghted pair-group average Euclidean distances i.¡or c.ì x tfr o ôl oo 0o \o oo ôl tîo o cñ l+ o\ o ch r r- \o r\ 1ô\o\o 0o rû F- d o\ ôl ôl Ê \f.?¡ o rr¡ \4' É \f c.l ï F- tn æ r\ c.¡ or clOOrc.lOO\cñxl--O-cldôldc.¡ôlñÉôlOÌ-.Cì-O\ô¡OrOrc¡rc,c¡\O\c'Éc>c)c)c¡Tc)cl\r\e'lc.¡-r-c.¡r-C.l;C.¡oo -.û C\F\OÌ..Ì\\OC-Ì*o'rt\f\f\f-f-Ft-Ì-f\f-F-l-f\o|tF-r'\\OÌ\\O\O\Or\\O\Of\f\f\t\F\Or-\Oo|rtia.-î-olrF-o'\¡--l,rt.-\O i¿.¡rr¡ralV¡rfrrôi^rr.lltlr r.¡r |'lrô¡ra¡rrrhrñl rnVlrôtôr Vìrr¡it¡rôr^qlrôi¡îratø¡r^(ñrôl hrrìrr¡rnVìrr¡r¡hVtrrì./tV¡r/l t.| (n (.) cl (fì cñ cî (.¡ ('l c.¡ ct¡ c1 ('l õ1 ca a1 cî câ cl añ c?¡ c'¡ c.r c.¡ cî cft cñ cl cî (?¡ c.¡ (a cf¡ ca cî c.t c1 c.¡ c?t cl cñ cî cr¡ fa câ c'¡ c?¡ cî cl a.r (.¡ cr¡ Figure 59. Cluster analysis of morphometric measurements of Arctic char from the commercial gillnet frshery at Paliryuak River in July 1992. Cluster N could represent a group. Sample identification number along abscissa. 126 A discriminant function analysis comparing the samples of nonspawners from paliryuak River 1992,Halovik River l99Z,Lauchlan River t992 and Lauchian River 1996 with the samples of spawners from the Ekalluk River system (Ferguson, Wishbone, Lady Pelly lakes) and spawners from Halovik Lake 1987, Halovik Lake 1993 and Kitiga Lake was carried out. The Squared Mahalanobis Distances (Table 21) suggest that the Halovik River 1992 andlauchlan River 1992 nonspawners were most similar to the Wishbone Lake spawners. The Paliryuak River 1992 nonspawners appear to be similar to the Wishbone Lake, Halovik Lake 1993 and Kitiga Lake spawners. The Lauchlan River i 996 nonspa\ilners do not show the same degree of similarity with any of the samples of spawners as the previous three samples did. There appears to be considerable heterogeneity in structure within the sample from the upstream migration of Arctic char into Freshwater Creek in 1988 (Fig. 60). Clusters E, G, J, M, N, O, P, D and B separate at a distance of about 5.5 or greater. Cluster O comprises the majority of the sample. This sample was compared to the samples of spawners taken from the Freshwater Creek system (Mount Pelly Lake) in I99Z and 1993 by discriminant function analysis (Fig. 61). Only a few specimens appeared to be simiiar morphologically to the samples of spawners. Individual clusters were compared by DFA with the two samples of spawners (Fig. 62 a,b,cd). Only a few specimens from Cluster O (Fig. 62c) appeared to be similar to the 1992 and 1993 samples of spawners. The ciuster analysis of the upstream migration of Arctic char into Freshwater Creek in 1991 (Fig. 63) reveals three possible clusters based on morphology. Clusters C and D separate from one another at a distance ofabout 6.1 and cluster D separates into 127 Table 21. A comparison of Squared Mahalanobis'Distances among samples of Arctic char spawners from the Ekalluk River system (Lady Pelly, Wishbone and Ferguson lakes), Halovik Lake r987 and 1993, and Kitiga Lake, and the samples of nonspawning Arctic cha¡ that were taken at Palir¡rak River lgg2, Halovik River 1992, Lauchlan River 1992 andlauchlan River 1996. STAT. Sguared Mahalanobis DisEances DISCRIM. AI.IA¡YSIS GROUP I-ADY PELLY L WISHBONE L FERGUSON L HALOVIK L 93 KITIGA L HALOVIK L 87 Ø É LADY PELLY L 0. 00000 ¿t. J tvLI 18.86604 18.17392 27 JþIUZ 10.56732 IIJ WISHBONE L-. 21 .3701.1 0 .00000 13.47847 3 .78007 4 87 48'l ¡ð. oyy /J z FERGUSON L 18.86604 L3 .4'1847 0.00000 14.02393 ¿JUIÞ 18.17439 HALOVIK L 93 LO. L t J>¿ 3 .78007 14.02393 0.00000 4- ?. I 027't2 12 -9964€j KITIGA L ¿ t .JoLv¿^ ^^ 4 .8'7 487 U) 19.25016 8.027'72 0 00 000 19.78512 HALOVIK L 87 1 0 q67?2 1n 1?d?o 1t o6â,10 1ô ìôcra Ø HALOVIK R 92 JI..J/YUÞ 8.24780 ?1 7qq?1 L3.25572 14.02908 28. 63830 É. 30 . 93 624 9.75078 19.55601 'z r¡J I..AUCHL R 92 14.80345 15. 92375 28.I36L7 o z PALIRYU R 92 28.07032 5.88160 20.24806 6.28965 7.79344 18.27318 z I-AUCHL R 96 38.12983 L6 .7 6287 18.47163 17.05565 ¿J. /JI /I 14.86516 o- Ø FRESHWATER CREEK UPSTREAM MIGRATION 1988 Unweighted pair-group average Euclidean distances b.) oê ËRRRËtRFNFÊRËHHËËf;RÈHRFFFÑFRÊËeßeÉEËÊRÊËËFFHËÊßRRFFËRRÊÊÊËÊRËRFFFNNFFEFFËEFgRRREeHÊËRËËgFËgRFRËNNNneFFf;ÊËFFFfFfHcÈßËfnÊËÊHFR Figure 60. Cluster analysis of morphometric measurements of Arctic char from the 1988 upstream migration into Freshwater Creek 1988. Cluster O couid represent a group. Sample identification number along abscissa. 4 ^ atll AAA .: tr a^ o oa- u3rä e{ trn tr tJ o !.-¡ 1 os o O A ô o trl -rl -^ - M. tr ED r-rtr rr ox d toð^o ooo^åi tr: tr o qÆÞog u H tr tro oôo o-o ^ 9 o o oo""po8"t"gä%8 o t\) -! E fuf ñ,' oo o tr oE"'tr tr ooo"-oo=o- o o.,3 oÔo u trF oto tr tr -4 -6 -,4 -2 0 2 4 6 Root 1 Figure 61. Discriminant function analysis of morphometric measurements of Arctic char from spawning aggregations taken in the Freshwater Ceek system (Mount Pelly Lake 1992 and 1993) and a sample of nonspawning Arctic char from the 1988 upstream migration in Freshwater Creek. 6 6 5 O FRESFÍWATER CK.1988 5 O FRESTM'ATER CK.1988 I] MT. PELLY L.1992 o MT.PELLYL.1992 4 o MT. PELLY L.1S93 4 o MT.PELLYL.1993 3 3 t' aa f a atr 2 a' 2 .& tt ug t rt N tlo. E Ë1 o ó1ó oÛooooo o oos go fr ooo É, 0 O9 0 oBoo oo" d o oo o tr oo -l -1 o o " =r:'T+ "sF"doiq Ê oo -2 -2 dttr -3 -3 a þ 4 012 -8 € --4 -2 0 Rool I Root I 6 a O CK.1O88 5 FRES}M'ATER CK.1988 FRESTTWATER MT. PELLY L. 1992 o MT.PELLYL.IO92 4 MT. PELLY L.1093 l. r MT. PELLY L.1993 tro 3 tt .' o t l, 2 .o a Õo O O tto . a. oooo oE (! N ^ ^ ^ oJo o^ Ë1 " fo.s3.""T^ oo 8' t o odíó uo -+ 8o f #c o 0 - o "î:.þ'}i'-xî;onoo . I "- -"t": or" 8ocr" oþ" s E %r-o"_" {,r.f "" -t ø o ^o- E E_u o"t¡ "" .)oo9trtrEo 6O -2 ooqu .3 d 4 0 -5 -3-2-101234 -4 -3 -2 -1 12 Root I Rool I , Figure 62. Discriminant function analysis of morphoT.!{. measurements of Arctic char from spawning aggregations'taken in the Fréshwater Creek system (Mount pelly iake tggZ Ma 1993) and different clusters (Fig. 60) of the 1988 upstream migration. The comparisons are: (a) Cluster J, (b) Cluster K, (c) ClustérN, and (d) Clusters E, G, O, D and B. FRESHWATER CREEK UPSTREAM MIGRATION 1991 Unweighted Pair-grouP average Euclidean distances ÊRËHËFRaãsÍHRËFñänËFEËËÊËÊEËËËËEËËË$F58äã*$8ËËËääEEEË5EEê$$ãåäRã:;RåFËilñxFËÈEnEËEË&EÈEËf åxJ.ÍHsssxxxxxxxxssàrxsxsxssxxiixäxx¡iiiHä:*iÍHHHxHxilslir*i¡($xxãxxxrF.åxÃÃxåxr;sãEF.xs;xHxÃãsx;; of Arctic char from the 1991 Figure 63. Cluster analysis of morphometric measurements C, E and F could upstream migration intã Freshwater Creek. Clusters along abscissa' represent difierent gloups. Sample identification number clusters E and F at a distance of about 5.5. On this basis I considered clusters C, E, and F as having group structure. A discriminant function analysis comparing each of these groups with the two samples of spawners (Mount Pelly Lake) taken in 1992 and 1993 revealed no similarity between cluster C and the spawners (Fig. 64a) but some similarity with cluster D and the spawners (Fig. 64b). Cluster D was further divided into clusters E and F. Cluster E showed no similarity in morphology with the two samples of spawners (Fig. 64c) but cluster F appeared to be indistinguishable from the spawners (Fig. 64d), particularly those from i993. The cluster analysis of the upstream migration of Arctic char into Freshwater Creek in 1994 reveals the presence of two possible groups and a number of apparent outliers (Fig. 65). Separation of clusters M and N from the remainder of the specimens occurs at a distance of about 5.5 and they separate from one another at a distance of 5.4. The discrimnant function analysis comparing this entire sample with the samples from the spawners taken from Mount Pelly Lake in 1992 and 1993 showed that the groups appeared to differ (Fig. 66). The cluster analysis of the sample of Arctic char taken in the upstream migration into Jayco River in 1990 reveals the presence of one main group and a few outliers (Fig. 67). Cluster D separates from the outliers at a distance of about 5.3. No samples of spawners were available from this system with which to compare this group. However, the mouth of the Jayco River is only 8 km from the mouth of the river system that drains Char and Fish Trap lakes (Fig. 7,8). Local residents of Cambridge Bay suspect that Jayco Lake Arctic char may overwinter and spawn in this system. Therefore, a discriminant function analysis of the samples of spawners from Char and Fish Trap lakes and the 4 'O FRES}M'ATER CK.199f CK.1991 O o FRESTMIATER 3 MT.PELLYL.T992 o MT.PELLYL.1992 o MT.PELLYL.1993 . MT.PELLYL.1993 o 2 'ooo c a OE o qo oo o +tr.' I o. oQo ooo oooo o oo ¡fto ..o.ool 'Ëo oo ,& o ooo oo iio É, .oô _oo É. .: o o Ert 0 o:' . "do {o -1 o O¡ tr '; "]"þ_þ-. tr "" :: :t " ""* -2 o o o ooooo oo a a -8 Root 1 3.5 r I O 1901 (^) O 3.o FRES}M'ATER CK' UJ FRESN¡'ATER GK.I99I I O MT. PELLYL.'1992 o MT.PELLYL.1992 I o 2.5 + Il'lT. PELLY L,1993 r MT,PELLYL.1993 o 2.O E¡fD o D ¡,O 1.5 o t gtr 1.0 a g I o-D (\ o f! o 0.5 o aa Ér¡o o ¡oooo3 o.tr,,R Ëlö o É oa É, o^ tlñoo o.o o I ooo o- o "o o Ç " o o" f to Þ 4" o oooo o -0.5 oa f O^ o o rl ooloo o "o -1.0 o oÉ tro o i aoo o ooo os"Iu Ú -1.5 o tro tr 6 -2.0 d C -2.5 -3 4-?-2-10 -4 -202 . Root t Root I of Arctic char Discriminant function analysis of morphometric measurements Figure 64. (Mount fro* rpu*ing agþregations taken inihe Freshwater Creek system pelly Lake lígzáialggl)and different clusters (Fig. 63) gf the 1991 C, (b) Cluster D' (c) upstream migration. The comparisons are: (a) Cluster Cluster E, and (d) Cluster F' FRESHWATER CREEK UPSTREAM MIGRATION 1994 Unweighted Pair-group average Euclidean distances BA J K N (r) Þ of Arctic char from the Figure 65. Cluster analysis of morphometric measurements M and N could upsrream migration into Freshwater creek lgg4. clusters along abscissa' reprer"ni ãifi.r.nt groups, Sample identification number 5 l- o FRESHWATER cK. 1ee4 I I u MoUNT PELLY L. 1992 | | n¡ourur PELLY L. 1e93 ooo tr o tr-Eitr tr frr nntr-d o oo8i.""*".;Ëp:a Ë oo* c{0 Etr;"u () Crl E ()-4 :*{:urltrþ d É. F u oo A ttr (}J -2 (t oooo ^ A t¡t a -3 -4 -5 ^ ,6 2 4 6 -6 -4 -2 0 Root 1 measurements of Arctic char 66. Discriminant function analysis of morphometlic Figure Creek system (Mount ,pu*rrìrrg aggregations taken in ihe Freshwater fro* Arctic char from the pelly Lake tgigZ and a sample of nonspawning ^¿iqq:) Creek' 1994 upstream migration in Freshwater Linkage Distance (, t, t-rr N) }J Þ È h ! r¡ h (',t (J¡ 33096 33092 33131 H 33124 '- 5J L¿L t_t (D 331 19 ^ 33239 :J 33 138 *.r- ô 4H Ë 33r25 \vr-u^V¿ 3) LZ¿ 4Eæ9Évt -.(D o 33133 Eì F¡ ''r C)Þo) 33128 c- ^t99 :+-Ë.9F ri AJ- 33126 x -ir. \< 33136 I - u-q øl o ¡-Ê' 33135 Ë Êlsììi.^ o 30Èi= 33127 çn ä:.8 33723 -t I J V 0 Þ q"l 33134 AÞF 33120 F x< x r,EC= VYAH 33137 v / d¡isFÞ -(D 33130 H <'?i' 33t29 *gü |f,r3 33098 Þ a(D 33115 . \.1 ol i+ffi ¿va Ø=Èe 33112 =(ogõ= EE 33108 33101 ä€ v}] 331 18 ö") 331i3 ltPe È* 33102 PL (o$t, (D=-¡'lÈ 33093 -: H\J oo r-t Li. 33106 CD() z 33097 .J 6s 33 i04 (o ÊPPX (o 33103 '+ o 33107 0aE9 :' AH YH 33099 -.P HvË + 5) tJZ uDo 33114 Êl- H V 33117 V Hv 33109 Êv ^ (D 33111 33105 'l 331 16 33100 33095 33094 331 l0 33091 9EI It I sample from the Jayco River 1990 upstream migration \¡/as carried out. The Jayco River 1990 sample appears to be a separate group from the Char and Fish Trap lakes samples (Fig. 68). All Chi-square values with successive roots removed (0.1) were significant (p < 0.001). The variables that contributed most to the discrimination were head depth (HDD), trunk length (TTL), and body depth (BDD) in that order (Table22). The Jayco River 1990 nonspawners were characterizedby large mean head depth (Fig. 69a), long mean trunk length (Fig. 69b) and small mean body depth (Fig. 69c), compared with the spawners from Char and Fish Trap lakes. The relationship of trunk length to head depth for these three samples is shown in Fig. 70. The cluster analysis of the sampie of Arctic char taken by the commercial gillnet fishery at the mouth of the Ellice River during the 1990 upstream migration reveals the presence of one main group and a few outliers (Fig. 71). Cluster F separates from the outliers at a distance of about 5.5. Further separation of cluster F occurs at a distance of about 5 but may reflect intra-group variation at this level. This is the only sample of Arctic char that I was able to obtain from the mainland. I was not able to obtain a sample of spawners from this system. However, I wanted to compare a sample of Arctic char from the mainland with samples from Victoria Island. Therefore I carried out a discriminant function analysis between the Ellice River 1990 sample of nonspawners and the geographically closest samples of spawners from Victoria Island. The latter inciuded the samples from Mount Pelly Lake 1992, Ãnderson Bay Lake 1993, and Anderson Bay Lake 1994 (Fig. 2). Results show that the Ellice River sample is distinct from these three samples of spawners (Fig. 72). The variables that contributed most to the discrimination were head depth (HDD), body depth (BDD) and pectoral fin length (PCL), in that order JAYCO R. 1e90 CHAR L. 1991 5 FISH TRAP L. 1991 ^ ^ A 3 o ^ ^ o A c{ o tr () tr C)Á ooo o E tr É.r oo oo gs oo tr 9O Añ trEI tr oooo o oo o o Htrh o o ocD tr; o A tr OO o o o oÐ i*; trE o tr u" 4 Otr ,foo o o rt u tr 2 3 4 5 -5 -4 -3 -2 0 Root 1 of morphometric measurements of Arctic char Figure 68. Discriminant function analysis and Fish Trap Lake in 1991 from spawni ngaggregations taken in btrar Lake the 1990 upstream migration and a röiããrí"tsiawning Arctic char from in JaYco River' t39 of morphometric measurements Table 22. Summary of the discriminant function anaiysis and a sample of of Arctic char spawners from Char Lake and Fish Trap Lake, in Jayco River' ' nonrpu*oirrg Arctic char from the 1990 upstream migration Crl1ÃT Discriminant Function Ãlalysis Summary g, N of vars in model: 8; GrouPing: GROUP (3 grPs) DTSCR]M. étep (1'6,192j p< .0000 ¡ìI'IAI,YSÏS wifï*'Lanì: r.80 I --|- 1.76 I I --l-, ? t.n I o L__J[*ll " o J :rL__l 1.68 [--] IT T t1.96'Stct. Dev. a cl EI t1.00'Std. Dev. 1.60 o Mean 224 Ir,ll 220 J F o -t ?-16 HÜTI :r L__1 I I 2.12 r+ E t1.965td- Dev. b E t1.00'Std.Dev. 2.08 -l- o Mean 2.18 2.14 L10 o Ê z.oo o o zo2 1.98 Ï *1.96'Std. Oev. C l-] t1.O(rstd. Oev. 1.94 o Mean rïr"r? * FTSHTRAP L. "Tâ$.. (a) (b) trunk lengfh (TTL), and Figure-.-Þ-- --69. Acomparison of mean log head -d.pt GDD), char spawners from Char (c) body depth iBDD) among samples of Arctic Lake andFitn ttup Lake in 1991 and a sample of nonspawning Arctic cha¡ from the 1990 upstream migration in Jayco River' 1.86 1^82 o oo o o a 8oo oo o 1.78 -o o o oo g@3$o6> o 1.74 öp "ã t¡n'''v oL' oo ä-òo o 1.70 o o % Bq. CD oo ""o o go ^o&" e l: 1.66 o F. Uoo fL 1.62 UJ 2.06 2.10 2.14 2.18 2.22 2.26 2.06 2.10 2.14 2.18 2.22 2.26 Él o JAYCO R. 1990 CHAR L. 1991 <( 1.86 UJ o 1.82 o o 1.78 o 1.74 o oo o 1.70 o o o 1.66 oo 1.62 2.06 210 2.14 2.18 2.22 2.26 FISH TRAP L. 1991 LOG 1-RUNK LENGTH Figure 70. Aplot of log trunk length (TTL) against log head depth (HDD) for Arctic char spawners from Char Lake and Fish Trap Lake in 199L and a sample of nonspawning Arctic char from the 1990 upstream migration in Jayco River. 33185 33t77 33t43 33164 33162 0a 33180 oõ 33156 \) 33152 - 33t82 oq -O 33186 :9ã 33157 f, eXà YQfi 33154 (f 33r87 m l- E5Êl 33 160 Þ ¿1 K r ocjË' 33183 o ¡. i'-' 33 181 m iD -:- 33 155 üoq;' 33r59 çn F¡5 g R qË 33188 =(õm 33 158 TI mõ'n x sl ã JJ IOJ aìir-ÞJ :6õ 33184 =OrrO. O. tÁ iI^.oÉr¿ I. 33161 R€ 33r79 = g tÎ]õ 33151 =P.nTM P ts.(, 33171 =(o b 9¿iH 33153 * õ ? dõ 2cË 33167 Ê¡ 33142 i 33165 33 139 7bl ___l ELL¡CE RI"O MOUNT PELLY L. 1992 I I ANDERSON B.1.1993 I ANDERSON B. L. 1e.s4_l n EE o En -tr tr o tr o ó) oo !EnËS- oo o o ."ts ä';-"ålBg.++ ooo o oo I ntr -.* o o-ô O c{ 5 o ro +t {+ oQ d,o ooOO E0o trA oLÞìo M.4 ++ oo +l* A o o oo o I ^ À a^ Ào (! ^^" â o + å ia ^^^ Aâ ^ A ^ ^ ^o^ -,4-20:¿ Root 1 char Figure T2.Discriminant function analysis of morphometric measurements of Arctic from spawningaggregations taken in Mount Pelly Lake 1992 andAnderson Bay Lake in tégj and ßgq, and a sample of nonspawning Arctic char taken byihe 1990 commercial gillnet fishery at Ellice River' r44 (Table 23). The Ellice River char had a large mean head depth (Fig. 73a) and mean body depth (Fig. 73b) and short mean pectoral fin length (Fig. 73c) relative to the others. Only the Anderson Bay 1994 sample had a mean body depth similar to the Ellice River sample. The relationship of head depth to body depth for the four groups is shown rnFig.74. Comparison of Samples of Spawners and Nonspawners Using Meristics Discriminant function analysis using meristic variables was carried on the same comparisons of Arctic char spawners as those using morphometric variables. The first comparison was among samples of spawning Arctic char from Ferguson, Lady Pelly and Wishbone lakes. Although there is evidence of group separation (Fig. 75), there is also considerable overlap. All Chi-square values with successive roots removed (0,1) were significant (p < 0.001). The meristic counts that contributed most to the discrimination were anal fin ray count (ARC), pelvic fin ray count (VRC) and pyioric caecacount (PYL) in that order (Table24). Those were the only variables selected in the discriminant analysis. The sample from Lady Pelly Lake was charac terized,by a higher mean anal fin ray count (Fig. 76a) and higher mean pyloric caeca count (Fig. 76c) than the samples from V/ishbone and Ferguson lakes. The sample from Wishbone Lake had the lowest mean pectoral frn ray count (Fig. 76b) of the three samples and the sample from Ferguson Lake had the lowest mean pyloric caeca count (Fig. 76c) of the three samples. The discriminant function analysis of meristic variables for the remaining comparisons of spawners revealed less discriminating power than the above comparison. In three of the other comparisons, only two variables were selected, and in one, only one variable was selected. Anal fin ray count (ARC) was selected as the most effective 145 Table 23. Summary of the discriminant function analysis of morphometric measurements of Arctic char spawners from Mount Pelly Lake 1992, Anderson Bay Lake 1993 and Anderson Bay Lake t994, and a sampie of nonspawning Arctic char taken by the 1990 commercial fishery at Ellice River. STAÎ. Discriminant Function Analysis Summary DISCRÏM. Step 8, N of vars in model: 8; Grouping: GROUP (4 grps) A¡¡ALYS I S Wilks'lambda : .04380 approx. F (24,412) =33.346 p<0.0000 WiIks' Partial F-remove 1-1oIer. N=153 Lambda Lambda (3,142) p-Ieve1 Toler. (R-Sqr. ) LOGHDÐ r43L92 107.4037 0.000000 507'702 492298 LOGPCL voo¿Lt¿ .66L235 24.2499 .000000 797301 ¿v¿oY> !UtröUU 067435 .649538 25.5390 .000000 422499 577 50 1 LOGPOL 05 64 98 . I IJ¿öJ 13.7195 .000000 510440 4 8 9560 LO6,D(W 052001 .842323 ð-Ëbu5 .000020 84477 4 155226 I ô¡/:aÞn o47'196 .9t6429 q. JIþq .006030 4q3 t qJ 554251 LOGTTL 060681 '. t ¿LóJO t8.2402 .000000 5t44},t .IZÞ5U J LOGDOL 0551 I 1 .7 9317 8 12.29'7r .000000 Ðru/ol q¿YzJ9 t46 r.86 1-82 T- - U^ 1.78 o 1 I l--r-I r-t-l" lt-_l o 1.74 I | | | ll o I 1.70 ' Irr:L lr-L-l 1.66 Frl E t1.96'Std. Dev. e E t1.005td. Dev. 1.62 o Mean L20 2.16 2.12 l- r,ll"l o 208 o zu L-JL_l J --T--lflL-J . I | | 2-AO T T t1.96-Std. Dev. b E t1.00'Std.Dev. 1.92 o Mean 2.O8 ..--f-T 2.U i-r 2.æ nl"l J r.s6 T,l'll I Io o I f-- J + 1.92 *l"l+-T-I ll | | Itrl--.----..]-l ^ lll 1.88 - ri.96*st¿. Dev. ñ :r E r1.oestd. D€v. T, 't.u o Meen ELUCER. MT,PELLYL. ANDERSON ANDERSON 1990 1992 BAYLI993 BAYLí994 Figure 73. Acomparison óf mean log (a) head depth (ID?)' @) body depth @DD)' and (c) peJtoral fin length (PCL) among samples of Arctic ðhar from spawning aggregations taken in Mount Pelly Lake 1992 aúA¡derson Bay Lake in 1993 atd,l994,and a sample of nonspáwning Arctic cha¡ taken by the 1990 commercial gillnet fishery at Ellice River. 2"22 o 2.14 o 2.06 ""rhå#*8'J" '*g.M;: o L98 t- 0- 1.90 1.76 1-82 1.88 UJ 1.58 1.64 1.70 1.76 1.82 1.88 1.58 1.64 1.70 É) ELLICE R. 1990 MOUNT PELLY L.1992 ocl 2.22 01 o (t {À o 2.14 o . -J ^þ"; oo ooo g 2.06 o o^09 o ot?8"8" oi.oftd ooo 1.98 o 1.90 1.70 1'76 1-82 1.58 1.64 1.70 1.76 1.82 1.tì8 1.58 1.64 BAY L. 1994 ANDERSON tsAY L. 1993 ANDERSON I.OG HEAD DEPTH samples of Figure 74. Aplot of log head depth (HDD) against log body depth (BDD) for Aictic charlrom spawning aggregations taken Mount Pelly Lake 1992 and Anderson Bay Lake in 19Þ3 aod9gq,and a sample of nonspawning Arctic char taken by the 1990 commercial gillnet fishery at Ellice River. 5 @ | * wrsHBoNE L. Li L_l_ElqtrsoN L. q o o al ^a¡¡r+J.A + '^ ^ +B c{ +a o 4^t * *Tgtr òo o + { À 4+-.o o gor o t aa* a o ge o - n_,at o &.0 f^** t+t É o + S,c, *, j'o o è + + : ]^t "^ o oo -1 +À+tQo+ od o +++b o ++'Fd + .2 + + + .3 + =¿l 4 4 -4 -.3 -4 -1 0 ? 3 Root 1 Figure 75. Discriminant function analysis ôf meristic counts from samples of Arctic char spawners from the Ekaltuk River system (Ferguson, Lady Pelly and Wishbone lakes). t49 Table 24. Summary of the discriminant frrnction analysis of meristic counts of Arctic char sparilners from the Ekalluk River System (Lady Pelly, Wishbone and Ferguson lakes). STAT. Discriminant Function Analysis Surnmary DTSCRTM. Step 6, N of vars in model: 6; Grouping: GRoUP (3 grps) ANAIYSIS Wil-ks I Lambda: . 6l- 6? I approx . F (12 ,296) =6.1476 p< . 0000 Wil-ks I Partial F-remove l--Tol-er. N=156 Lambda Lambda (2,148) n- ì ar¡o l Tol-er. \¡\ eYr. / .ARC 7 27 853 847 404 l_3 32555 0000 05 ybt-J¿I / 038 653 \rÞ¡/- 684543 901 0 17 I LZYS I 000447 97'7342 o22658 PYI Y5óO¿ö öJö4 b 009216 o06267 UGR 645875 954 9 60 490L4 033 030 Y ¿Oóö I U / JI.IY BRC 621 048 Yö J bJJ 1 231.34 29487 4 97 2640 v¿ I JOU DRC 625668 98 58 02 t_ 06578 347 08 9 9 687 01 o3]-299 150 120 11.5 11.0 T 10.5 O l"lT _r < 10.0 9.5 9.0 +[1tri'-I- i I 8.5 - r1.96'Std.Dev. dl r1.005td. Dev. . tt.u - o Mean 112 10.8 T-T' 10.4 ll 10.0 I s.6 l"l-lE 92 lll"lltl 8.8 8.4 IÏ T t1.965td. Dev. b l-] t1.00'Std. Dev. 8.0 tr Mean 56 TT l,T 50 J o- HEË 38 IÏ:T lI t1.96'std.Dev. G E t1.00'Std.Oev. o Mean LADY PEELLY *ill8*t FERGUSoN Figure 76. Acomparison of (a) anal fin ray count (ARC), (b) pelvic fin ray count C/RC), and (c) pyloric caeca count (PYL) between 5amFles of Arctic char spawners from the Ekalluk River system (Ferguson, Lady Pelly and Wishbone lakes). 151 discriminator in two of the comparisons as was pyloric caecacount (PYL) for two others. Upper gill raker count (UGR) was selected as the most important discriminator in one comparison of spawners. A comparison of means of these three meristic counts for the twelve samples of spawners examined in this study is shown in Fig. 77 . The samples from Lady Pelly Lake, Anderson Bay Lake 1993, andFish Trap Lake had the highest mean anal fin ray count (ARC) of all groups (Fig. 77a).The samples from Anderson Bay Lake 1993 and Anderson Bay Lake 1994 had the highest mean pyloric caeca count (PYL) of all the samples (Fig. 77b). The sample from Halovik Lake 1987 had the lowest mean upper gill raker count (UGR) of all the samples (Fig. 77c). Analysis of variance of these three variables across all 12 samples together revealed significant differences in mean values G < 0.00i) for each variable. All pairs of means were compared using the Least Significant Difference (LSD) test. Results of the comparison of mean anal f,rn ray count are shown in Table 25, those for mean pyloric caeca count in Table 26, andthose for mean upper gill raker count in Table 27.The mean upper gill raker count for the sample from Halovik Lake 1987 was significantly different from that of all the other samples of spawners. A pattern was evident when the samples from the six Ekalluk River upstream migrations of nonspawners were examined for meristic variation. The sample from the 1992 upstream migration showed the greatest variation in six of the eight meristic counts taken when compared with the other five samples (Figs. 78,79). Also, the 1992 sample had the lowest mean anal fin ray count (Fig. 78a), the lowest mean upper gill raker count (Fig. 78b) and the lowest mean lower gill raker count (Fig. 78c) compared with the samples from the other five upstream migrations. As well, the 1992 sample had the H fi' tstç (D { ARC ìJ UGR PYL b in J4ÈÞ JfD foP n l.) s E È È à s. s I I 3 fi E 3 3 E äs (¡ (rl oqr o(,r træ ÉaB(D ö,1-- -'c' LADY PELLY L 1987 äE H r-r--:F E' WISHBONE L. 1994 G *ÈÈ'rÞ q FERGUSON L. 1996 t-B E.EX-a Èajg/ HALOVIK L. 1987 i Gt (DËí c;g HALOVIK L. 1993 G vh èþ. L. 1994 # KITIGA IJP Lì Ê t_l aÊ) NJ '< MT. PELLY L.1992 # '-t ^C) 1993 G e,É MT. PELLY L. 6 Þl ANDERSON B. L. I993i # õ>H^ ÐF ANDERSON B. L. 1994ì # uq i-l F-l-T--H trI ìJ CHAR 1.1991 (l z-r r+ (t. Fæ 5v FISH TRAP L.1991 íd ¡c, ã:1(Do øÞ. . . IH Þc) " IH IH Fls gHu() FF5 seE (Dc) ã55 sqE u, (n GaÞ sqq (1, (t PP oc) (na CL ÉI oo |+¡O cL cl. oo bboo ss ÞÉ (D(D;b ä:+ fs d^ c)Yts.H o l'f Hv r53 Table 25. Pair-lvise comparisons of the mean values of the meristic variabie anal tin ra,v count (ARC) among the twelve samples of A¡ctic char spawne¡s examined across the study area. using the Least Significant Difference (LSD) test. (+ = minimum 0.05 sisnificance level) sT.åÎ. LSD Eest,'variable .¡s,c u¿r\ ¿¡1-'\.¡.r Þ-¡lr¡!.ìlilisc F,rr Pas t, licc Te (l) t?l i3) {4} (6i L]KUU f 10.29412 9.535424 9.644{14 9.500000 9 . 63{ 615 9.954545 I.ADY PELLY L. t1j 000000* 000054+ 000000+ .029742+ WISHBONE L 000000+ 894759 341{74 . uu+õ)or l.2l r'ìqnôÁ. FERGUSON L. t3l 000000* 46391 4 HALOVIK L. 87 t4l 000051* 894759 ¿lþJy /.{ qðùo>1 .037402+ HALOVIK L. 93 tsl 000000* 314474 qððovr I¡ 1X / | q. KITIGA L. t6l 0281 42+ 004856* UJUUÞO 037 402* 038719* 111 t1 MT. PELLY L 92 l,.lf--r 1 000001* 704190 MT. PELLY L 93 t8l 05 690 6 uJrt / yö 1v:zð) T /J¿{OU ql ANDERS. B. L.93 tel 000003* nllntoÁ* 001 450* nnnl r . ¿¿¿rJo ANDERS. B. L 94 [10] 000002+ 557455 /vÕ-tou ÞUð:'{I 846871 .01505q+ CHAR L. [ 11 j 000002* 1?4043 þOUJJU FISH TRAP L. l.12'. 915567 000202* nn??1q* 002424* 001641* . lao¿v¿ STAT. LSD test; variable ARC GENER.A¡ Probabilities for Post Ënn To t rl fRt fq] flnt tar/tl l ì Lr¡(UU I o oôono r LV. LOLZ> >.ovlL.t¿ LV.¿t¿tJ LADY PELLY L. t1l 000001* 000002* 000002* WISHBONE L. t2J LYO¿JU 0547 98 000003+ L1 4043 000?02* '198 FERGUSON L. t3l 71147 4 .,|.YJ¿ö¡ 000296* 460 I ZöJJ¿ 0022L5* HALOVIK L. 87 1 nÁo1 ? 001450* 608941 ??q?qq 002424* t4l ''lo4L90 HALOVIK L. 93 tsl I'JqOU 0 0 0151r þ þUfJU 0 016 41* KITIGA L. t6l éJ>¿t> 222736 04 5054* 093026 LJO ¿V ¿ MT. PELLY L 92 I7I 000821* OIUÕ¿J 004061* MT. PELLY L 93 t8l ¿ oþvð.L t62514 rol nq,q 160481 ANDERS. B. L 93 tel 000821* nnn qôo* 000921 * 600897 ANDERS. B. L 94 [ 10J oLvó¿J !o¿J t I 000509* 002 1 85* CHAR L. I11l z ð tuÞ5 000921 * 004432" FISH TRAP L. 112) 004061* IþU¿{öI þUUö Y / 002185* 004432* t54 Tabie 26. Pair-lvise comparisons of the mean values of the meristic variable pyloric caeca count (PYL) among the twelve samples of Arctic char spawners .xámined across the study area. using the Least Significant Difference (LSD) test. (* : minimum 0.05 signifrcance level) STAT. LSD tesÈ; variable (¡E l\ Ë fvìtr Prcbabili.ties for PoS E fJnc To f I I (2Ì (4) {6} GROUP ¡{ú.ou/ù.{ 46.05000 ¡l{-/þ/¡{¿{ 4 9. 00000 4l | \ | /â 45.30435 <1+ I.ADY PELLY L. t1I 00b99b' 000207* tt>vLz ^^^,t 0082,17+ WISHBONE L i/ln:oo:+ VJ¿¿öJ { t 1Y/tl qlq?10 121 ñôô.)¡1.ì+ FERGUSON L. 00't240+ . / I.U þUJ þ / )uJ5 Lrl * HALOVIK L. 87 t4l 0072{0* .0t24T 1 03215{+ HALOVIK L. 93 .000451+ /LõouJ 0t2471 * O >J¿Jõ t5l qd+ KITIGA L. l6l .008217+ n??1 . ô/t?á,)ô* MT. PELLY L 92 t7I ^n^tì11+ 5 0 0190 0017 02* 326244 MT. PELLY L 93 l8l .114087 Y rJqÞJ 46L926 Lqv r¿ó .600650 7 018 71 ANDERS. B. L 93 tel 000201* 000005* 478448 nônñ11* 000411* ANDERS. B. L 94 [10] 000388* 000012+ 5058 4 0 .000025* 000631* f 11' CHAR L. I t¡l .400940 u/ð/ö1. 004616* +¿o¿>ó nôqc¿ 1 * 052864 FISH TRAP L. 1.121 . qJUJõ.{ u I Y / átl L2r6'Ì2 4?0531 - t / / t þþ 25?485 t1l t,, i8) l¿ t (10 ) t¿r, I L¿ I qô 1 Á1 En 1^?1 À', \JÈTUU .E 4 4 .04 651 4 6.00000 to JV. ÀV tr .l. l.lovót . JOJO¿{ ' ' L.ADY PELLY L. t1l 000011* 114087 .400940 4 5038 4 y/JqoJ Lt /ÚISHBONE L. t2l 043620* 000201* 000388* .078781 !> ¿öv =ERGUSON L. t3l 500190 qo L> ¿o 0 0 0005* 0000L2* . 004 61 6* L¿LO I ¿ TALOVIK L. 87 t4l 001702* I40L28 47 8448 50584 0 . Lt¿o¿Jo 420537 IALOVIK L. 93 tsl ¿OOLJL þUU ÞJU 000011* 000025* .009541* I/rloo {TIGA L. t6l 326244 70L87L 000411* 000631* .052864 257 485 VIT. PELLY L 92 t7l 243864 000000* 000001* . 0004 5 6* 048186* VIT. PELLY L 93 t8l ¿cJö oq 01714 6 " 020306* .¿>v¿vL ).t ðvzÞ C.NDERS. B. L 93 000000* 01714 6 * ña1 IUöJOl- tsl ^1'1* \NDERS. B. L 94 [10] 000001* 020306* .048843* L¿V'1,LL ]HAR L. f 111 2 qo) o'l â,11* 000456* ^1.1 048843* 8Lt29L =ISH TRAP L. 1,12J 04aLa6* I204!L H | | /Y I t55 Table 27. Pair-r,vise comparisons of the mean values of the meristic variable upper sill raker count (UGR) among the t',velve samples of A¡ctic char spawnèis examined across the study area. using the Least Significant Di-fference (LSD) test. (* = minimum 0.05 significance level) J I}\I . ILSD iest,' uariabLe UGR (:¿N C..Vì.i,r l9rcbabiliEies for pcst l.ícc TesËs ItfÀ¡.fOV¡. I }L\IN EFFECT: GRCUP tr) I tzl t3) I tql {s} tel GROUP | 11.07843 | tO.eoooo 10.s8140 | g.gz:orr I 4 nnr 1Á?* I .002203* . 000003 l'trl1 ? .Ji.Jqyð .000849" .Þ¿{Þ/1J . 058 '11Q?ôn 453 . TL¿J>¿ .000913* . 9 YÞUJö .648148 ANDERS. B. L 93 ..iruo¡{õ .38234'7 ôn1 STAÎ. LSD test; variable uutl GENERAL Probabilities for PnçÞ I{oc Tests MA¡TO\ß. MAIN EFFECT: GROUP t?) (8) (e] {10¡ alt¡ GROUP 1 0 t ta ¡^^ . 75000 11.00000 10.?4194' LV.^ t L\¿t 10.45652 11.00000 + I-ADY PELLY L. 0 41137 . t o¿L>v 058 623 047591* ,000102* . t þ¿IJV t1l 11R?nn WISHBONE L. t.21 JJ¿þ¿> 410648 521941 J.l I >q¿ FERGUSON L. t3l 313498 . LL¿J' ¿ JÓ ¿Jq I 482847 450338 . LL¿J>¿ HALOVIK L. 87 t4l 000848* .000813* nn1 1 1.5 1 1.0 10.5 zF 10.0 I s.s É s.o ï= 8.5 Í t.3 T t1.96'Stcl Dev. t-"1 11.00'Stc[ Dev. o Mean 13.5 12.5 É. t¡l $ rr.s z I ro.s É, J 6 s.s 3 B.s t1.g6:SE. De¡/. t.c 11.005td. Oev. Meân 18.5 17.5 t¡¡ 16.5 = z 15.5 ul 14.5 J o É 3-t¡¡ l3.s J 't2.5 I t1.9€'Std.Oev. 11.5 Ef t1.00'Std. Dev. EI Figure 78. Acomparison of (a) anal fin ray count (ARC), (b) upper gill raker count (UGR), and (c) lower gill raker count (LGR) among the six samples of nonspawning Arctic char taken in the upsteam migration in the Ekalluk River (1 988, 1990, 1991, 1992, t993, t994). 157 12.5 12.O l{ < zF 11.0 {^ q z L J 10.0 U) -T- +1.96'Std. Dsv. l---'l t1.00'Std. Dev. tr Mean 13.4 12.8 zt- o 1t) tt.o ul6 Þ v) $ r.o z -E lo.¿ --T-- *1.96'Std. Dev. f---'l r1.oo'std. Dev. o Mean aÊ z ^ 3 r¿.s é 14.o z tr 13.5 J $ rs.o oF H rzs 12;0 lI *1.9eStd. Dev. f---l 114 *1-oo'std. Dev. tr Mean EI(ALLUK EI(ALIUK EKALLUK EIqILUK EKALLUK E}(ALLUK 1988 1990 1991 19C2 t993 1994 Figure 79. A comparison of (a) dorsal fin ray count (ARC), (b) branchiostegal ray count (BRC), and (c) pectoral fin ray count (PCR) among the six samples of nonspawning Arctic char taken in the upstream migration in the Ekalluk River (1988, 1990, 1991,1992, L993, lgg4). t58 lowest nlean dorsal fìn ray court (Fig. 79a) of the six samples. The mean bra,nchiostegal ray count of the 1992 sample \.vas similar to that of the other five samples but agai'. the variation in this count was the largest of the six samples (Fig. 79b). The lgg2sample also had the lowest mean pectoral fin ray count of the six samples (Fig. 79c). Genetic Analysis Electrophoresis Five samples of spawning Arctic char and nine samples of nonspawning Arctic cha¡ from the study area were examined by electrophoresis (Table 28). Electrophoretic patterns for the enzymes superoxide dismutase (SOD) and phosphoglucomutase (pGM) were invariant across all sample locations while those for esterase (EST), phosphoglucose isomerase (PGI) and isocitrate dehydrogenase (IDH) showed very little variation across all samples. Therefore, these enzymes were excluded from further analysis. Electrophoretic variability was detected among samples when malic enzyme (ME) phenotypes were examined. Malic enzyme is tetrameric with a model of two duplicated loci proposed to account for observed variation in brook char (Salvelinus fontinalis) (Stoneking et al. 1979). For this species, one locus (ME-2) is fixed and one locus (ME-1) is variable with three electrophoretically distinct alleles designated ME-l (100), ME-1 (50) and ME-1 (0), based on the greatest to least mobility, respectively. Andersson et al. (1983) conducted an electrophoretic survey of 33 enzymes of Arctic char from 10 Swedish localities. Their results revealed 52 detectable loci, 37 of which were considered useable population for studies. One of these enzymes was malic enzyme. These authors found two anodal zones of activity for this enzyme in Arctic char. The less t59 Table 28. Samples of Arctic char spaumers and nonspawners examined by electrophoresis. Location Spawners / Nonspawners N Lady Pelly Lake 1987 (Ekalluk R.) Spawners 51 Ekalluk River Upstream 1988 Nonspawners )l Ekalluk River Upstream t 990 Nonspawners 50 Ekalluk River Upstream l99l Nonspawners 50 Ekalluk River Upstream 1992 Nonspawners 51 Palir¡rak River i992 Nonspawners 52 Halovik Lake 1987 Spawners JU Lauchlan River 1987 Spawners 29 Mount Pelly Lake 1992 Spawners 45 FW Ck. Upstream 1988 Nonspawners 120 FW Ck. Upstream 1991 Nonspawners 70 Char Lake 1991 Spawners 46 Jayco River Upstream Nonspawners 49 Ellice River Upstream Nonspawners 50 160 anodal zone, froltt tltuscle extracts, was represented by three bands and was assumed to rcpresent the expression of a duplicate pair of loci (ME-l and ME-2) fìxed for different alleles.This deviation fiom the expected fìve-banded pattern w'as observed in brook char and was assumed to be caused by reduced expression of protein products specified by tlie ME-l locus relative to those of the ME-2 locus (Stoneking etal.1979). Partington and Mills (1988) found a th¡ee-banded electrophoretic phenotype for malic enzyme from liver tissue in Arctic cha¡ from ten British lakes. Two loci were assumed to be involved but no variablilty was foutd at either one. Andersson et al. (1983) observed no variability for malic enzyme among Arctic char samples in their study. Analysis of electrophoretic phenotypes of malic enzyme for Arctic char from this study suggests that the variable zone is a duplicated pair of loci, one being invariant, and the other variable for two alleles (J. Reist, pers. comm.). In this study, three distinct three- banded electrophoretic phenotypes predominated in all samples that i examined (Table 29). The phenotype with the symmetrical band pattern was assumed to be the heterozygote, based on a banding pattern expected for a tetrameric enzyme (May 1980). Two other phenotypes, not shown in Table 29,were observed occasionally in some of the samples. These may be due to possible variation at the presumptive invariant locus, a third allele of low frequency at the variant locus or variable activity resulting from uneven sample treatment such as differing freeze-thaw regimes (J. Reist, pers. comm.). Therefore, I ignored these phenotypes. The phenotypic patterns I observed are consistent with an inheritance pattern based on a single variable locus with two alleles. These phenotypes could be synonymous with ME-l (100/100), ME-l (100/50) and ME-l (50/50) phenotypes reported by Stoneking et al. (1979) for brook char, given that the r6l Table 29. Results of electrophoresis of lvlalic Enzyme. Phenotypic frequencies and gene frequencies are shown as well as a test for Castle-Hardy-Weinberg (CFIW) equilibrium. (* = 0.05, ** = 0.0i significance levels) IVÍALIC ENZYME PHENOTYPES o AA AB BB I ¡-¡ I 'GfI I¡|EE IEEEEE I v æt GENE FREQ. + N a b T2CIIW Lady Pelly L. (SP) 17 17 2 36 0.71 0.29 1.29 ns Ekalhi< R.88 (NS) 10 l) 6 31 0.56 0.44 0.04 ns Ekalluk R.90 G{S) T2 16 5 33 0.61 0.39 0.04 ns Ekalluk R.91 CNS) 10 24 t2 46 0.48 0.52 0.19 ns * Ekaliuk R.92 (NS) 18 13 t3 44 0.56 0.44 6.74 * Palir¡rak R92(NS) 11 11 t2 34 0.49 0.51 336 Halovik L. 87 (SP) 9 11 TÀ 24 0.60 0.40 0.11 ns Lauchlan L.87(SP) 6 15 4 25 0.54 0.46 1.41 ns Freshw. Ck 88(NS) 25 46 16 87 0.55 0.45 0.24 ns Freshw. Ck 91CNS) 19 3T i0 60 0.58 0.42 0.32 ns Mt. Pelly L.92 (SP) 5 15 9 29 0.43 0.57 0.24 ns Jayco R. 90 (IIS) 9 2l 7 37 0.53 0.47 0.94 ns CharL 9i (SP) t3 l6 7 36 0.58 0.42 0.27 ns Ellice R. 90 (NS) 19 12 5 36 0.69 l.3g 0.27 ns 162 electrophoretic mobility of ME-1 (50) is intermediate between the ME-1 (100) and ME-l (0) brook char alleles, I theret'ore present these data based on this model. All five samples of spawners examined by electrophoresis satisfied Castle-Hardy- Weinberg equilibrium as did seven of the nine samples of nonspawning Arctic cnar (Table 29).The samples of nonspawners from the Ekalluk River 1992 upstream migration and the Paliryuak River 1992 commercial fishery did not. Both of these samples showed a heterozygote deficiency. it is interesting to note that within the Ekalluk River 1992 sample, the subsample of morphologically similar Arctic char in cluster J (Fig. a2) satisfied Castle-Hardy-Weinberg equilibrium Otr:27, X2: L 96, 1 dÐ. Similarly, when the subsample of Arctic char in cluster N (Fig. 59) of the Paliryuak River 1992 sample was examined, it satisfied Castle-Ha¡dy-'Weinberg equilibrium (Ì.tr : 14, Xt : 0.28,I df ) as well, with respect to phenotypic ratios of malic enzyme. Comparisons of gene frequencies between samples of spawners revealed a significant difference (p < 0.05) between those from Lady Pelly Lake and those from Lauchlan Lake 1987 (Table 30). The gene frequencies for the Lady Pelly Lake sample were signif,rcantly different (p < 0.001) compared to the sample of spawners from Mount Pelly Lake in the Freshwate¡ Creek drainage. Lady Pelly Lake spawners were marginally different (p : 0.05) when compared with the spawners from Char Lake. Spawners from Halovik Lake 1987 and Mount Pelly Lake showed a marginal difference (p: 0.05) in gene frequency. I63 Table 30. A comparison of gene frequencies of lvlalic Enzyrne among samples. (* : 0.05, ** :0.01, i'{'* :0.001 sigruficance levels. ns : not signif,rcant, mar: marginally significant) SPAWNERS: Lady Pelly L. Halovik L. (87) Lauchlan L. Mt. Pelly L. (92) Halovik L (87) ns Lauchlan L. * ns Mt. Pelly L (92) *** mar ns Char L. mar ns ns ns SPAWNERS AND NONSPAWNERS : LadyPellyL. Spawners vs EkallukRiverNonspawners 1988 mar LadyPellyL. Spawners vs EkaliukRiverNonspawners 199i :i'* Lady Peily L. Spawners vs Jayco River Nonspawners 1990 {< Mt. Pelly L (92) Spawners vs Ellice River Nonspawners 1990 t:F 164 Within river systems, Arctic char spawncrs from Lady Pelly Lake were significantly different (p .0.01) in malic enzyme gene tiequencies compa¡ed rvith the sample of nonspawners from the Ekalluk River l99l upstream migration. Lad-v- pelly Lake spawners were marginally different in malic enryme allele frequencies (p: 0.05) when compared with the sample of nonspawners from the Ekalluk River 1988 upstream migration (Table 30). Between river systems, the Lady Pelly Lake spawners were signifìcantly ditTerent (p < 0.05) from the sample of nonspawners in the Jayco River 1990 upstream migration. The spawners from Mount Pelly Lake in the Freshwater Creek drainage system were significantly different (p < 0.01) from the sample of nonspawners taken from the Ellice River commercial fishery in 1990 (Table 30). The model of a single variable locus with two alleles that I used to explain phenotypic ratios observed in this study is reasonable. All samples of spawners satisfied Castle-Hardy-Weinberg (CHW) equilibrium. The two samples of nonspawners that did not satisfy CHW equilibrium both showed a heterozygote deficiency, consistent with genetically mixed samples. Satisfaction of CHW equilibrium of a subsample of morphologically similar Arctic char (cluster analysis) from within each of these mixed samples further supports the model. Mitochondrial DNA (mt DNA) Thirty-nine specimens of Arctic char were examined for sequence variation in the mitochondrial DNA (mt DNA) control region (352 base sequence adjacent to the tRNA Proline gene). Specimens consisted of spawners from Halovik Lake 1993 (N=11) and r65 Auderson Bay Lalie 1991(N-:5), as u,cll sunplcs of nonspawners from thc upstream migrations at the Ellice River 1990 (N:5). the Elcalluk River 1993 (lrt=1¡ and the Ekalluk River 1994 (NI:17). Tluee hundred and fìfiy-trvo bases were examined. One valiable base position was fouud at sequence position 99 (Fig. 80). The reference specimen, from the Ekalluk River 1994 upstream migration (specimen No. 40271), had Thymine at the variable base position and was designated as Haplotype 1. Haplotype 2 had Guanine at the variable base position and Haplotype 3 had Adenine at the variable base position. Thirty-five of thirty-nine char examined were Haplotype i, three were Haplotype 2 and one was Haplotype 3 (Table 31). Table 31 . Mitochondrial DNA haplotypes found in samples of Arctic char spawners and nonsoawners durins this studv. Location Haplotype 1 (T) Haplotype 2 (G) Haplotype 3 (A) N Ellice R. 1990 5 5 Ekalluk R. 1993 1 1 Ekalluk R. 1994 ITl/1 2 ïl Halovik L.1993 t0 1 11 And. Bay L.1994 5 5 Given the lack of variability observed among these samples and the resources I had available to me, no further investigation of mitochondrial DNA sequencing was undertaken. t66 ATTÀA.TAGGA TGATtrTGAA AGTTffiTGGG TAJq.r{GACGGA trCCGTGTTA * GTTGGAGTTT TGTTAA.TGTA GCAATTATCT AGGTTêrrAJÂ\r{C AACCTAGTTG Haplotype 2 AACCTAGTGG Haplotype 3 AACCTAGTAG GTTATTATCA CGTGTTTAGC TTATGT,A,rq¿'T CTTGGGTTTA TGCTGATATA TGAGGCICTTA AATTCACTTA TGTTGATAAT ACATATGATG TACTACTCAT CATACAGGTA TTGTATATAT GGGTAAATAC ATAATATGCA ATATTATACA TAGATGTATT ATGACACTAA TTIGTTGAGA TACAATATTC ATTATTGTAC ATATTAGTGG CTCGTCAGAGG GTAGTTTAAC TTAGAATCTT AGCTTTGGCT GC Figure 80. The 352 base sequence of the mitochondrial DNA control region adjacent to the tRNA Proline gene for Arctic char examined in this study. Haplotype i is displayed with an asterisk indicating the variable base position. The short segment (10 bases) indicates the difference with Haplotypes 2 and3. 167 Stablc Isotope Annlysis Stable isotope analysis was carried out on seventy specirnens of Arctic char during this study (Table 32). Table 32. The range of values of the stable isotopes of carbon ('3C), nitrogen ir5N), and sulfur (rrS) found in Arctic char examined during this study. The number of specimens examined is in brackets. Stable Isotooe ttc o/oo t'N o/oo o/oo Location 'os Jayco R. 1990 -26.0 to -18.8 (2s) 7.5 to 14.7 (24) -1.7 to 14.1 (1s) Char L. 1991 -22.2to -19.1 (1s) 12.7 to 14.9 (15) 10.6 to 15.3 (15) Ellice R. 1990 -24.r to -21.1 (10) 72.2to i4.9 (10) Halovik R. 1992 -24.3 to -2 1 .8 ( 1 0) 9.7 to 12.4 (10) Ekalluk R. 1992 -23.6 to -21.4 (10) 9.8 to 11.7 (10) The carbon and nitrogen isotopes of nonspawning Arctic char from the upstream migration in the Jayco River 1990 showed a wide range of values (Fig. 8ia) compared with those from the Ellice River 1990 (Fig. 81 b), Char Lake 1991 spawners (Fig 8lc) the Halovik River 1992 (Fig.81d,) and the Ekalluk River 1992 (Fig. 81e). The char from Jayco River 1990 appear to be feeding at three trophic levels whereas those from the remaining samples appear to be feeding at one trophic level. Arctic char in the Ellice River and Char Lake samples appear to be feeding at a higher trophic level than those o o E o oo&oo B oo "Yobs ñ ñ-Cr-O- o- vv^o o uo o(f b c o 6 -18 -27 -24 -21 -18 -27 -24 -21 -18 -27 -24 -21 z CHAR LAKE 1991 ro JAYCO R.1990 ELLICE R.1990 16 l-J 14 6 ouJ 12 o8o o o o Otso 10 8o oo d e 6 -18 -27 -24 -21 -18 -27 -24 -21 HALOVIK R.1992 EKALLUK R.1992 DELTA 13 C O/OO migration Figure 81. Carbon and nitrogen isotopes in Arctic char taken from the upstream in (a) Jayco Rivei 1990, 6) Ellice River 1990, (c) Char Lake spawners 1991, qa¡'tú. upstream migration in the I{alovik River 1992, and (e) the upstream mígration in the Btattut River 1992.The solid lines denote trophic levels as per Hesslein et al. (1991). t69 from the Halovik River and Ekalluk River samples. The sulfur isotopes of the Jayco River sample also shorved a wide range of values compared with those of the Char Lake spawners (Fig.82). Jayco River Arctic char appear to be feeding at several trophic levels and may be feeding on fbod soruces from different areas. Char Lake fish appear to be feeding at one trophic level and apparently from a food source from a single location. Micro-PIXE Analysis of Otolith Strontium Concentrations Strontium concentrations in water samples taken from the spawning locations were compared with mean strontium concentrations in the early growth zones of otoliths 2: of spawners captured there (Fig. 83). There is a strong linear correlation (r 0.86) between the two. Micro-PIXE line scans were carried out on at least some specimens from each of the spawning aggregations examined (Table 33). Four distinct patterns of line scans \¡/efe observed (Fig. 8a). The typical anadromous line scan (Fig. S4a) shows a relatively low strontium concentration in the early growth years that appears to remain constant until the char goes to sea for the first time. Seaward joumeys are indicated by the marked spikes in strontium concentration. The strontium concentrations do not retum to baseline levels between successive peaks. However, a return to baseline levels was observed in some specimens that apparently did not go to sea in successive years, based on otolith annuli. The second type of anadromous pattern observed (Fig. 8ab) shows a relatively high strontium concentration in the nucleus of the otolith followed by a decline in the early growth period. The strontium concentration then remained relatively constant until 15.5 a b o o 14.5 o OO o o o & o 13.5 ooo o o oo s o o o 12.5 z oìc r.c) 11.5 o l- J -J [rJ o 10.5 9.5 o 8.5 4 4812 16 20 -4 0481216 20 JAYCO R.1990 CHAR LAKE SPAWNERS 1991 DELTA 34 S O/OO Figure 82. Sulfur and nitrogen isotopes in Arctic char taken from the upstream migration in (a) Jayco River 1990 and (b) Char Lake spawners 1991. The solid lines denote trophic levels as per Hesslein et al. (1991). OTOLITH Sr = 39.526 + 5.1242* WATER Sr Correlation: r = .93 200 180 ANDERSON BAY L. 160 E o- o- 140 L U) T MOUNT PELLY L. t- 120 oJ \¡ l-- o LADYPELLYL. O -/ 100 -a'' O WISHBONE L. BO 60 6 10 14 1B 22 26 30 WATER Sr (ppm) Figtrre 83. The relationship between strontium in water samples taken at the spawning grounds and strontium in the early growth regions of otoliths of Arctic char spawners capturecl there. The clashed Iines represent the 95olo confrdence limits. 172 Table 33. A suinmary of lv[icro-PDC line scan analysis of strontium in the otoliths of A¡ctic char spawners exarnined. Location Line Scans Anad.' Non.' %NÍat. Dist. to Sea ,lñ 4.i/ < ,1 t-- Lady Pelly L. )i +7 r4(2) 3s(2) v'/o JÌ ÃTTI no/ rìo 1- Wishbone L. 60 58 52(1) 6(0) 70 l\lll À 1 /a^\ 1/^\ ¿.no/ < l-_. Ferguson L. +'^c 43 +t\L2) z\v) vt /o J ttlll f r^1^--:1- T Ot ,.t/1\ 1/^\ a^o/ /l < 1-- r1i1IUVIIr. L. O / 13 t T\r,, r\v., LV 70 ÎJ l\lll Halovik L. 93 JL &tO^o 1s(3) 3(0) 6% JU l\._lll f.r:¿-^ f ôô ôô /(\ r\ru5.1 L. LL ¿L\J ) 23% lf i(m /l (/^\ 1 /^\ 1À1--. Mt. Pelly L.92 1I'l 6 J\v,, r\v,, ^o/v/o rr ítll .rr /f¿ Tì^11-. T ô1 1l l1 I'l //1n\ i1 0/ 1A1-- lvr-r. .F çil) L.7J ll II r r\rv,, 7L/O l1 Älll And. Bay L.93 31 .lll 4(0) ^o/v/o 0.3 lan ôo a< 1tl^\ a\//^\ r\Il-- And. Bay L.94 LO LV r / \u,, 7\v/ ^ñ/v/o u-J lt_llr ,t¿ a Char L. 4tU J 3( 1) 33% 12 km T 11 a 1n 1--. I'rùuTr: -L "l--^-rrilP L. ll t 3( 1) 33% tv Ätu Number in brackets indicates the number of line scans showing a matemal effect. * Anad. indicates the number of Arctic char in the sample that displayed an anadromous profile. Non. Indicates the number of Arctic char in the sample that displ ayed a nonanadromous profi I e. Sr concentration in Raw X-ray counts (ppm : Raw X-ray count x 5.2304 - 5.575) È o E o o ñ' tsl å È ä g âeÊ.F Ñi+dqsiãEÉ H É äFä, tl +ã *Ë;.* =-' õãõp¡6"91 F tre¡1çlOH.ÞflËËB*ä I *F*ïËä ä F*trH B g 3 g \¡ iIi.Þõr --)-- (,) E'B Ë'ã ã ä ã -<---.'s *ã*{.È9 .o ËË[Éiåä F €rn€:n q a q 8qsË ã g g Ë ? ä'Ç s F SH ÉH,ES G- H E Þ P Hä E õ Ë õ Ë =ä __-..-_- ã H' âa'e T=¡=--L'_ Eì1äÊ i -::- E PH F ã' : -\.:- >Ë õ -È-- f{ P C F+(D-¡o '=-_-d+ gÊ'3õä .: ã. FE ã g 9Ft9 ä'q T õË oÞF õÞF É. \Y 174 tlle char first went to sea, as observed in rhc typical line scan of Fig. 8a(a). The initial high strontium concentration in the nuclear area of the otolith is believed to be a caused by tlte female making a short excursion to the sea to feed during the summer prior to spawning (see Discussion). This so-called "maternal effect" was observed more fiequently in samples from some locations than in others (Table 33). The third pattern observed from the line scans was the typical nonanadromous pattern (Fig. Sac) whereby the strontium concentration in the otolith remains relatively constant from the nucleus to the ed_ee. The fourth pattern (Fig. Sad) is that of a nonanadromous A¡ctic char that shows the "maternal effect" in the nuclear portion of the otolith. Anadromous Arctic char were captured at every site (Table 33). Nonanadromous Arctic char were also found in some of the samples. Most of the spawners from Lady Pelly Lake were nonanadromous. All the specimens examined from Kitiga Lake, Mount Pelly Lake 1993, Anderson Bay Lake 1993, Char Lake and Fish rrap Lake were anadromous. Most of the specimens examined from Wishbone Lake, Ferguson Lake, Halovik Lake 1987, Mount Pelly Lake 1992, and Anderson Bay Lake 1994 were anadromous. The pattern of the line scan provides evidence of anadromy. The incidence of char showing the "matemal effect" appears to be related to the distance of the spawning ground from the sea (Table 33, Fig. 85). A total of sixty-seven percent of the samples from Ferguson Lake showed this effect. This spawning ground is only 5 km from the sea. In contrast, only one of the specimens from Wishbone Lake, 98 km from the sea, showed this effect. Interestingly, none of the specimens from Anderson * % MATERNAL EFFECT = 53.791 - .6715 DISTANCE TO SEA (km) Correlation: r = -.69 100 C MOUNT PELLY L. 1993 t- BO uC) l! LL [rJ J z 60 É. t-tlJ 40 -l (, FISH TRAP L. z g g CHAR L. o :tr= o KITTGA L. (î) 20 o HALOVIK L. 1e87 s LADY PELLY L. o o HALOVTK L. 1S93 WISHBONE L. o 0 0 20 40 60 B0 100 DISTANCE OF SPAWNING LOCAT¡ON FROM SEA (km) Figure 85. A cornparison of the percent of spawners clisplaying the "maternal effect" of strontium concentrations in the otolith primorclia with the distance of the spawning ground from the sea. 176 Bay Lalie showed this effect even though the outlet of this lake to the sea is only 0.3 km long. It is, however, very shallow and may not allow passage of fish at times. In order to remove the "maternal effect" so that the otolith strontium concentration that is cha¡acteristic of the rearing waters can be measured, an average of the strontium concentration over a distance of i00 pm, starting at a distance of 200 pm from the centre of the otolith, was taken. The "maternal effect" was generally not observed beyond this distance. The diameter of the otolith is about 500 ¡rm post-hatch (J. Babaluk pers. comm.). The mean strontium concentration in the early growth portion of otoliths of spawners examined varied among locations (Table 34). It ranged from a high of 182 ppm in Anderson Bay Lake 1994 spa\ilners to a low of 66 ppm in Halovik Lake 1987 spawners. In marked contrast, the sample of nonspawners from the Ellice River on the mainland had a mean strontium concentration of 1040 ppm. The mean strontium concentration in samples of spawners was compared by analysis of variance (ANOVA). Group differences were signifrcant þ < 0.001). Pair-wise comparisons of group means (Table 35) revealed that all were significantly different with the exception of Halovik Lake 1987 and Halovik Lake 1993, Kitiga Lake and Ferguson Lake, and Mount Pelly Lake 1993 and Kitiga Lake. The strontium concentration in the early growth regions of the otoliths of spar,vriers was plotted against age (Fig. 86). In each case, strontium concentrations did not vary with age within each sample, whereas means differed among samples. The sample 177 Table 34. A sunmary of mean strontium concentiation in the early growth region of otoliths of A¡ctic char spawners examined. Location Mean Sr (ppm) Standard Dev. Range (ppm) T T)^1I-- T /to 1A ¿1 Li;tLry^J-- .cçlrJ L. .tO 10s.5 LlJ.VL 78.7 - 138.7 \I7J.LL^-^ T r-O 1 ll YV lSlluulrtr t-. JO 96.4 La.1)'lf\ 69.0 - i39.0 /11 1¡ ô^ 11/l0 110^ Ferg:uson L. 1 12.8 rLL.()-zro.v n Halovik L. 87 5 66.3 t.2+^,1 fi.a - n.7 TT^t^-il- T ô,) ,ln ,t.rF7 r1atuvüt r-. 7J .tl -1I t-v 1t^ ^ 13.67 r L.v - I J- l f./:L: 1 aF, 11C\ r\rrr5¡1 L. LZ I T'.V II.\JU1/l - ^ ^¿ 73.9 - 218.0 l1 1ao A 14 <^ 1^t 1 1trÀ,l lvft. Peiiy L.93 LLO.+ LlJ.J ) rvl.r - -tJr.î a¿ 101 1< an Ard. Bay L.9,1 LV LOL.V^ LJ.L I 156.2 -2i3.3' rllli^^ T):--^- ñ^* /rì r lt 1^Pr^ 101ôã !:llrr-ç l\lvgr 2v 't7 lv.tv.v^,.1^ ^ ^¿zg.t.7+ ^A LZ I .V - LOLL- I ' Eliice River is a sample oinonspawning Arctic char but is inciucied for comparison. Table 35. A comparison of mean strontium comcentrations (ppm) among all samples of Arctic char spawners, using the Least Significant Difference (LSD) test. (* : minimum 0.05 significance level) STAT. LSD testi variable MEAN SR GENERAL ProbabiLitiès for Post Eoc Tests MÃNOVA MAIN EFFECT: GROUP (11 l2l {3} {4) {s} {6} {7} (8Ì GROUP 105.5132 96.35517 L72.78L4 70.98312 66. 33334 118.9536 128.4309 L82.O23L . .001145* 000022 * 0. 00 0000 * I-ADY PELLY L. t1l .003392* 03007 0* .000000* .000000* * * 00000 0 * 0. 00 00 00* WISHBONE L. Í21 . 003392 00000 1 .000000* .000066* .000000* \¡ 0. 000000 * oo FERGUSON L. .030070* .000001* .000000* .000000* . r.39065 003829* t3l 000000 * U. 000000* HALOVIK L. 93 14l .000000* .000000r. .000000* .533874 .000000* 0 * 0. 000000* HALOVIK L. 87 t5l .000000* .000066* .000000* .533874 .000000* 00000 1 07 033 o: 000000* KITIGA L. t6l .001145* .000000* .139065 .000000* .000000* .000000* .107033 000000* MT. PELLY L. 93 l7l ,000022* .000000* .003829* .000000* * ANDERS. B. L.94 t8l 0.000000* 0. 000000* 0. 000000* 0.000000* 0.000000* 0.000000* 00000 0 179 ARCTIC CHAR SPAWNERS MEAN Sr vs. AGE 22 - aî 20 ¡1 .,:l 18 GTD co ñ 16 C@ u!\.''wA^ñ 14 \l_:!- \\J \l-,\J t^l-- al 12 cco 10 8 20 80 140 200 260 20 80 140 200 260 20 80 140 200 260 LADY PELLY L. WISHBONE L. FERGUSON L. 22 20 rì 18 16 al tt LU 14 \i-!/ v î14't-, O 12 arv-î\ 10 @ I 20 80 140 200 260 80 140 200 260 20 80 140 200 260 HALOVIK L. 1993 KITIGA L. MOUNT PELLY L. 1993 22 al 20 o 18 16 (J L' 14 12 /-fTl 10 I 20 80 140 200 260 ANDERSON BAY L. 1994 MEAN Sr (ppm) Figure 86. A plot of mean strontium concentration in the early growth region of the otolith against age for samples of Arctic char spawners. 180 frorlr Fc¡tgusou Lakc shotvs the greatest variatioH u'ithin each age group, but was still consistent among age groups. It is interesting to note that few spawners over the age of fourteen years were observed in the samples from Halovik Lake 1993 and Mount Pelly Lake 1993. The frequency distibutions of strontium concentrations for the different spawning aggregations (Fig. 87) appear, for the most part, to have obvious modality and narÏow range. The range of values of otolith strontium concentrations by age group in samples of spawners is limited and clustered around the mean value compared with those in samples of nonspawners (Fig. 88). However, samples of nonspawners from each of the upstream migrations in the Ekalluk River show a greater range of strontium values within each age group compared with those of the spawners. There appear to be some "clumped" values amongst the samples from 1990, 1997, 1993 and 1994, whereas those from 1 988 and 1992 appear to be spread out within each age group. l8t DISTRIBUTION OF OTOLITH Sr BY SAMPLE 40 30 10 40 100 160 220 40 100 160 220 40 100 160 220 LADY PELLY L. WISHBONE L. FERGUSON L. 40 Ø o30z É. 20 u-l CN o10co oTL o0 z 40 100 160 220 40 100 160 220 40 100 160 220 HALOVIK L. 1993 KITIGA L. HALOVIK L. 1987 40 100 160 220 40 100 160 220 MOUNT PELLY L. 1993 ANDERSON BAY L. 1994 OTOLITH Sr (ppm) Figure 87. A comparison of frequency distributions of strontium concentration in the early growth region of the otolith among samples of Arctic char spawners. 182 EKALLUI( RIVER SPAWNERS AND UPSTREAM RUNS MEAN Sr vs. AGE 22 rTì 20 ,IR O ccc co 16 l.-ILL]J ^ævuw 14 ¡^ñ c@(o 12 ,. oæ 10 ñ 20 80 140 200 260 20 80 140 200 260 20 80 140 200 260 LADY PELLY L. (SP) vvfsHBoNE L. (sP) FERGUSON L. (SP) 22 2t 18 o l't (JU 16 /l a'ì a\ô ,^ vvv ^^ 1+ a\ al ñ'a \J \J \.J ^?,.nvw LU 12 lrY'\ l^rar ¡'^l CI L' \-¿ ^ ¿-1¡'1 ,/-tl 10 \J \J \J L\J \., \J oco I a\ ,'ì ,.ì o 2t 8t 140 20fr 280 20 80 140 2ût 2e0 2t 80 14t 200 zea EI(ALLUK R. 1988 EKALLUK R. 1990 EKALLUK R. 1991 22 20 o 18 16 \J U' o 14 f-"\ i/a fì ooo wvffi^ ñ oo vv 12 ^v ^^vv w co ooo co ooo ooo o oo o 10 ^^ \_,¡J I fffì o 20 80 140 200 260 20 80 140 200 260 20 80 140 200 260 EKALLUK R. 1992 EKALLUK R. 1993 EKALLUK R. 1994 MEAN Sr (ppm) Figure 88. A comparison of mean strontium concentation in the early growth region of the otolith against age among samples of Arctic char spawners from the Ekalluk River system and samples of A¡ctic char from the six upstream migrations into the Ekalluk River (1988, 1990, 1991 ,1992,1993,1994). 183 DISCUSSION Evidence of Stock Structuring Morpholog.v Life history studies of the freshwater form of Arctic char have revealed significant morphological differences among populations. Differences are found between and within lakes (Frost 1965; Johnson 1980; Hindar and Jonsson 1982; Jonsson and Hindar T982; Nordeng 1983; Gardner et al. 1988; Partingfon and Mills 1988, Venne and Magnan 1989; Reist et al. 1995; Alekseyev et al. 1997; Alekseyev and Pichugin 1998; Alekseyev et al. 1999; Alekseyev et al. 2000). Few studies, however, have focussed on differentiating stocks of anadromous Arctic char based on morphology. Dempson and Misra (1934) identified seven stocks of anadromous Arctic char along the northern Labrador coast using a multivariate analysis of meristic data. Pectoral fin ray and upper gill raker counts were the most effective stock discriminators. Their samples were taken during the return migration from the sea into fresh water and not from spawning assemblages. Reist et al. (1991) found morphological differences among anadromous Arctic char over a broad geographic range in the central Canadian Arctic. I present evidence that anadromous Arctic char spawners from geographically adjacent locations within the study area can be differentiated from one another on the basis of significant morphometric, and to a lesser extent, meristic differences. These differences are apparent between geographically adjacent river systems, and in a number of cases, within river systems. They can be distinguished from one another by at least one definable character difference and in most cases. by a number of such differences. 184 Therefore, they meet the criteria for discrete phenotypic stocks as defined by Booke (1e8 1). All morphometric and meristic characteristics have a genetic basis. However, because the expression of genes that code for some of these characteristics can be environmentally modified (Martin 1949; Svärdson 1952; Lindsey 1954; Loch l9j4; Bodaly 1977; Balon 1980; Todd et al. 1981) some researchers consider these characteristics as unreliable for stock identification (Clayton 1981). In fact, they can be as valuable for stock identification as other, more genetically related features. A set of quantitative characters, such as morphological measurements may contain more information than an equal number of "directly genetic" characters (Thorpe 1976). Their utility for stock identification depends upon the stock behaving as a cohesive unit whose members exhibit common responses to environmental conditions within their respective geographic boundaries (Casselman et al. i981). Clayton (1981), in a discussion of the relationship between organismal and molecular evolution as it relates to the stock concept, recommended that a combination of molecular and organismal data be used for stock identification pu{poses. However, he points out that there are situations where one or the other would suffice. Stock discreteness can be obscured by spatial overlap during various seasons of the year (Casselman et al. 1981). That is why it is crucial to obtain samples for stock identification from spawning aggregations. Sampling spawning aggregations increases the likelihood of a homogeneous sample. Coupled with this is the necessity to include as many year classes in the sample as possible. If morphological characteristics particular to a sample are consistent within the sample over many successive generations, this is 185 evidence of environmental anÜor genetic similarity from generation to generation. The morphological characters that I observed to be useful discriminators between stocks in this study showed this consistency between year classes within each sample. This is evidence that similar environmental/genetic influences have affected successive generations within each sample. The meristic characters that I examined in this study did not provide the level of stock discrimination that the morphometric measurements did. Ihssen et at. (1981a) recornmend that the two types of data be treated separately in multivariate analyses because the former are discrete variables and the latter are continuous variables. I examined the two types of data separately and found that where the meristic data showed group segregation, the results were identical to the group differences based on morphmetrics, especially for the three samples from the Ekalluk River system. The phenotypic stocks identified in this study are allopatric, because the spawning grounds are separated geographically. At least three stocks of Arctic char inhabit the Ekalluk River system, including those that spawn in Ferguson Lake, Lady Pelly Lake, and Wishbone Lake. The minimum distance between the three spawning grounds is about 45-50 km and the maximum distance is about 100 km by water. There is possibly a fourth phenotypic stock utilizing the Ekalluk River, based on the morphological differences evident among the sample from the 1994 upstream migration and the three samples of spawners just discussed. There are at least two discrete stocks that spawn in the Halovik River system, including those sampled in 1987 near the outlet of Halovik Lake and those sampled in 1993 upstream of the 1987 sample. The minimum distance between the two sampling 186 locations is about 2.5 krn. The 1993 sample was a pooled sample consisting of Arctic char taken from two areas approximately 13 km apart. However, the 1993 sample appeared to be morphologically homogeneous (Appendix II). Discrete phenotypic stocks of Arctic char inhabit Fish Trap Lake and Char Lake, both of which are part of the same river system that drains into Albert Edward Bay. The Char Lake sample was taken from two locations about 3 km apart and pooled. It appeared to be morphologically homogeneous (Appendix III). The Fish Trap Lake sample was a minimum of 2.5 km from the nearest Char Lake sample. The nonspawners from the Jayco River upstream migration appear to be morphologically distinct from the spawners from Fish Trap and Char lakes even though the mouths of both rivers are within 8 km of one another bv water. The samples of spawners from Mount Pelly Lake (Freshwater Creek system) taken in 1992 and 1993 were similar in all but three of the morphological characters. The differences indicate that they are discrete phenotypic stocks. The 1993 sampling location was within 500 m of the closest 1992 grllnet set. The considerable morphological heterogeneity observed within the samples of nonspawners from the 1988, I99l and 1994 upstream migrations in Freshwater Creek when compared with the spawners from Mount Pelly Lake suggest that a number of morphologically distinct stocks inhabit this system as well. With the exception of a small cluster (cluster F) from the 1991 upstream sample that appeared to be morphologically similar to the Mount Pelly Lake 1993 spawners, none of the other samples showed any morphological similarity to the two samples of spawners examined from this system. t87 At least two discrete phenotypic stocks inhabit Anderson Bay Lake, including those sampled in 1993 and those sampled in 1994. Although the precise location of the i993 sample is not known, it was not taken at the same location as the 1994 sample and Anderson Bay Lake is only 6.5 km in maximum dimension. Nonspawners from the Ellice River commercial fishery on the mainland were morphologically distinct from the closest samples of spawners (Mount Pelly and Anderson Bay lakes) on Victoria Island, over 100 km away. Clearly, phenotypic stock structuring within the study area exists on a broad geographic scale. However, it also appears to exist on a very fine geographic scale (< 1 km) as evidenced by the two samples of spawners from Mount Pelly Lake. The two samples of spawners in this study that are morphologically most similar to one another are those from Char Lake and Wishbone Lake. Interestingiy, these two sample locations are the two that are most widely geographically separated at present. Although the two lakes are only 18 km apart in straight-line distance, each is in a separate drainage system. Wishbone Lake flows west via the Ekalluk River system into Wellington Bay whiie Char Lake flows east into an unnamed river that empties into Albert Edward Bay. However, this was likely not the case during the time that Arctic char colonized this area after the last glacial period. Wishbone Lake is at a present elevation of about 25 m above sea level (asl). Less than I km northeast of Wishbone Lake lies an unnamed lake in the Char Lake drainage basin that is also at a present elevation of about 25 m asl. These lake basins would have risen above sea level at about the same time. between 1250 and 2500 years ago, based on a rebound rate of 1-2 m per 100 years (Johnson 1962). Perhaps the morphologically similar Arctic char stocks which inhabit 188 Wishbone and Char lakes today are remnants of an ancestral stock that colonized this area when suitable freshwater habitat became available. If that is the case, the morphological similarity of these two stocks appears to have endured and could be the result of similar environmental/genetic influences acting on both stocks since separation. The two samples of spawners that are most distinct morphologically from all of the others are those from Lady Pelly Lake and Halovik Lake 1987. The lake from which the Halovik 1987 sample was taken was apparently not inundated by seawater since glacial melt (Dunbar and Greenaway 1956; Wilson et al. 1958). Halovik Lake is at a present elevation ofabout 105 m asl, and could have been one ofthe first lakes in the study area to be colonized by Arctic char following deglaciation. Lady Pelly Lake is at a present elevation of about 30 m asl. Anderson Bay Lake, at an elevation of about 3 m asl, could have been one of the most recently colonized lakes within the study area. Clearly, the process of isostatic rebound is the force that determined when the land in different parts of the study area rose above sea level. The development of suitable freshwater habitat to support Arctic char followed. Given the present elevations of the different lakes involved, some would have become available for habitation before others. However, attempting to draw conclusions about present-day morphological similarities or differences based on different times of colonization is speculative at best. What exists today is likely due to a combination of the reshuffling of char stocks that occurred at the end of each glacial period (l.Iyman 1989) and the effects of thousands of years of natural selection for adaptation to local conditions. Power (1981) has attributed the formation of over 500 stocks of anadromous Atlantic salmon (Salmo salar) in Newfoundland and the Quebec-Labrador peninsula to such local adaptation following colonization. 189 The Arctic char exhibits extensive morphological and ecological plasticity across its range (Johnson 1980; Behnke i980). Nyman (i989) attributes this not so much to its wide geographical distribution but to the fact that it has lived and evolved near the margins of ice sheets. He maintains that this environment, where habitat change is pronounced, favours geographical isolation and the primarily lacustrine habitat occupied by Arctic char has augmented isolation between stocks. Genetics Genetic distinctness between two groups is evident if consistently significant differences in allele frequencies at one or more loci can be demonstrated between samples from the two groups (Ihssen at al. 1981a). Genetically distinct populations of freshwater forms of Arctic char have been reported throughout the geographic range of this species (Saunders and McKenzie 197I; Nymarì 1972; Henricson and Nyman 1976; Child 1977; Johnson 1980; Kornfield 1981; Ryman and Stahl 1981; Andersson et al. 1983; Hindar et al. 1986; Magnusson and Ferguson 1987; Partington and Milts 1988). These genetic differences were found among both allopatric and sympatric populations. However, little information is available on the genetic distinctness of anadromous Arctic char populations. The significant differences in allele frequencies for malic eîz¡iimethat I found among samples of spawners from Lady Pelly Lake and Mount Pelly Lake 1992 is evidence that there is genetic distinctness among anadromous Arctic char stocks within the study area. This suggests that there is reproductive isolation between those stocks. Unfortunately, I could not compare all samples of spawners in this study for genetic 190 distinctness because of limited resources. However, the genetic data that I present complement the putative stock structuring based on morphology. The significant differences in allele frequencies that I found when I compared the Lady Pelly Lake spawners with the sample of nonspawning Arctic char captured during the 1991 upstream migration into the Ekalluk fuver provides evidence that at least one other genetically distinct stock utilizes this freshwater system. Although this sample was most similar morphologically to the spallmers from V/ishbone Lake, I do not have evidence to prove that the Ekalluk River is its "home " stream. The most conservative interpretation is that at least two genetically distinct stocks of Arctic char (Lady pelly Lake and this sample of unknown origin) inhabit this region of the study area. The two samples of nonspawners that did not satis$r Castle-Hardy-Weinberg equilibrium provide additional, although indirect, evidence of genetically based stock structuring within the Wellington Bay area. Non-satisfaction of CHW equilibrium is evidence of non-random mating. A common cause is that the sample is comprised of an admixture of individuals from two or more populations that differ in allelic and genotypic frequencies (Ferguson et al. 1995). These mixtures are often characterized by a deficiency of heterozygotes (V/ahlund i928). This information is very useful if it is based on samples of non-spawning fish because it indicates that at least two genetically distinct stocks reside in the area of investigation (Utter and Ryman 1993). Indeed, the sample of nonspawners from the 1992 upstream migration in the Ekalluk River was characterized by a heterozygote deficiency. This sample also showed a high degree of morphological heterogeneity. A portion of the sample, whose members were mo{phologically similar (Cluster Analysis), satisfied CHW equilibrium when examined by itself. This is evidence 191 that Arctic char from at least two genetically distinct stocks migrated upstream in the Ekalluk River in1992. Andersson et al. (1983) concluded that the non-satisfaction of CHV/ equilibrium for esterase (est-2) based on a significant heterorygote deficiency from a sample of Arctic char from a Swedish lake (Västra Trollsvattnet) was a genetic indication of more than one population of A¡ctic char inhabiting that lake. The 1992 sample I obtained from the Paliryuak River, although not taken from an upstream migration, appears to be comprised of an admixture of Arctic char from at least two genetically distinct stocks feeding in Wellington Bay as well. This sample also did not satisff CHV/ equilibrium because of a heterozygote deficiency. Once again, a morphologically similar portion of this sample did satisÛr CHW equilibrium when examined alone. The genetic differences observed between the Mount Pelly Lake spawners and the nonspawners from the Ellice River 1991 commercial fishery, paralleled by morphological differences, are evidence of stock structuring between stocks on Victoria Island and the mainland. Interpretation ofputative stock structure based on differences in allele frequencies must be done with care. The implicit assumption is that allozyme markers are selectively neutral and that genetic drift is responsible for stock differentiation (Ward and Grewe 1994).If they are not, then a single panmictic stock with different selection pressures in different areas could be incorrectly identified as a number of genetically distinct semi- isolated stocks with restricted gene flow. On the other hand, two stocks that are truly isolated, but subject to similar selection pressures, might appear genetically uniform, and therefore incorrectly considered as parts of a panmictic stock. One way to avoid the former error is to shift to non-coding DNA markers, discussed later, which are less iikely 192 to be affected by selection (Ward and Grewe 1994). Another method is to ensure that the sample is comprised of spawners from a number of successive year classes. Homogeneity of genotypic/phenotypic characteristics among year classes within a sample is evidence of homing, the behaviour necessary to restrict gene flow. If homing can be proven, gene frequency differences, regardless ofwhether or not they are affected by selection, provide evidence of stock structuring When allozyme frequencies do not show evidence of differentiation, and thus there is insufficient evidence to reject the null hypothesis of a panmictic stock, it cannot be concluded that the samples represent portions of a panmictic stock although they may (Ferguson et al. 1995). Evidence from other lines of investigation, such as tagging and morphometric and meristic variation, should be used in conjunction with the genetic data to assess likely population structure (Ward and Grewe 1994). Such was the case in this study. Whereas I found no significant difference in allele frequencies of malic enzyme among spawners from Lady Pelly Lake, Halovik Lake 1987 and Char Lake, morphological differences among these three samples were evident. Morphological differences often reveal stock structuring on a finer scale than allozyme electrophoresis. Such was the case in studies of lake whitefish (Coregonus clupeaformls) in Lake Winnipeg (Kristofferson and Clayton i990). Two stocks could be separated based on significant differences in glycerol-3-phosphate dehydrogenase (G-3- PDH) allele frequencies. These differences were parallelled by morphometric and meristic differences. Further population discrimination was possible within each genetically similar group, based on morphological differences. Casselman et al. (1981) found better stock discrimination of lake whitefish in Ontario waters of Lake Huron usins r93 tagging data, population parameters and morphometrics, than with allele frequencies examined by electrophoresis. The electrophoretic data identified two large groups, within which further stock discrimination was possible with the other methods utilized. The study by Partington and Mills (1988) of nonanadromous Arctic char populations from ten British lakes focussed on growth, morphology and electrophoretic analysis. Significant differences were found among twelve groups of char from these lakes for each of 13 morphometric and two meristic variables. Distinctions could be made not only between allopatric populations, but also between some sympatric populations. Significant differences in allele frequencies for malate dehydrogenase (Mdh-4,5 (130)) and esterase (Est-l (115)) were found which clearly separated spawners from two basins of the same lake (Windermere). Canonical analysis of morphometric measurements showed a clear distinction between these spawning groups as well. In another study, Kipling and Le Cren (1984) found a high degree of f,rdelity (99%) to spawning sites in Windermere over consecutive years, based on tagging studies. Homing behaviour of this nature contributes to reproductive isolation within the lake, resulting in genetic differences over time. Genetic stock structuring on a small geographic scale has been demonstrated for Dolly Varden (5. malma) and brook char (S. fontinalis), two species closely related to Arctic char. Reist (1989) observed significant differences in allele frequencies for the enzymes superoxide dismutase (SOD) and glucose phosphate isomerase-3 (GPI-3) among anadromous samples of putative Dolly Varden from four adjacent river systems along the Yukon north coast and western Northwest Territories. Subsequent analysis has since confirmed that the species in question is Dolly Varden (Reist et aI. 1997). Meristic 194 differences were also noted between samples from these locations. The samples compared were anadromous spawners and all allele frequencies met Castle-Hardy- V/einberg equilibrium. However, when he examined anadromous spawners from two different locations within one river system (Firth River), Reist (1989) found no significant differences in allele frequencies for these enzyme systems. Jones et al. (1996) used alloryme analysis to detect high levels of population differentiation in brook char in Fundy National Park, New Brunswick, and eastern Canada. Most differentiation occurred among populations in different branches of the same river drainage. This genetic differentiation on a local scale is thought to be a product of small numbers of founders and subsequent population bottlenecks, and random genetic drift in combination with restricted gene flow between river branches. They concluded that little present-day gene flow exists among most of these populations. Angers et al. (1995) used microsatellite analysis to examine intra- and inter- population genetic diversity among samples of brook char from five lakes in close proximity to one another (maximum distance apart:22I{rrr) in Quebec. Microsatellites are a class of nuclear loci that consist of variable number tandem repeats or VNTRs (Bruford et al. 1996), thought to be selectively neutral (Ward and Grewe 1994). Strong inter-population diversity was detected with highly significant differences in allele frequencies in all but two pairwise chi-square permutation tests between populations at all loci. As well, numerous population unique alleles were found in all five lakes. I was not able to utilize microsatellite analysis in my study because the technique had not been fully developed for use with Arctic char at that time. However, Bernatchez et al. (1998) applied this technique to the analysis of gene diversity in anadromous Arctic 195 char from Labrador, Canada, using primers developed for other closely related species. They prefaced their study with a statement that predicting population structure of anadromous Arctic char may be complicated by their complex migratory behaviour and the lack of clear information about the extent of their homing behaviour. They analyzed six loci among 257 anadromous Arctic char taken from six locations along the Labrador coast and one sample from an inland lake in Newfoundland. The latter sample was used as a reference sample because it was not connected to the others by gene flow. Their samples were not taken on the spawning grounds. Their results indicated that all six loci were moderately to highly polymorphic. Significant genetic structure indices (Frr) and differences in allele frequencies were observed among most samples, as well as heterozygote deficiency (Wahlund effect) in all but one sample. Based on this, tirese authors rejected the null hypothesis of absence of genetic differentiation among the Arctic char samples, implying the existence of genetically differentiated populations with restricted gene flow on a microgeographic scale (< 10 km). They concluded that the observed heterozygote def,tcency \¡/as an indication of population admixture, because their samples were taken during upstream migrations. They reported that their results reinforce the view that anadromous Arctic char may possess strong homing capability. The high levels of polymorphism of microsatellite loci that Bernatchez et al. (1998) observed in their study was in marked contrast to low levels observed in studies of this species using alloryme and mtDNA analyses. Indeed,I found mtDNA sequence analysis of no value for stock identification within my study area and limited stock differentiation based on allozyme analysis. These authors suggest then that microsatellite 196 analysis potentially offers more sensitivity than allozyme and mtDNA analyses for the examination of fine-scaie stock structuring of anadromous Arctic char. Stable Isotopes Isotope ratios in substances can change due to various chemical and physical reactions. This "isotope fractionation" occurs in predictable ways as elements cycle through the biosphere (Peterson and Fry 1987). This fractionation reflects reaction conditions and thus provides process information. Stable isotope distributions also provide information about the origin of samples, or source information. The source is an isotopic baseline that can subsequently be shifted by fractionation (Peterson and Fry 1987). Stable isotopes can therefore provide information on diet and trophic level (Gu et al. 1996; Hobson and Welch 1992,1995). This information, in turn, can provide evidence of stock structuring (Welch and Parsons 1993). In animals, isotopic compositions of carbon and sulfur are a direct reflection of 0/oo diet but nitrogen values average 3 to 5 heavier than dietary nitrogen, mainly due to excretion of isotopically light nitrogen in urine (Peterson and Fry 1987). Therefore, 0/oo nitrogen isotopic values increase 10 to i5 in many food webs due to an increase in 15N 0/oo content of 3 to 5 per trophic level (Minagawa and Wada 1984). No change with increasing trophic level is evident with sulfur (Mekhtiyeva et al. 1976; Peterson et al. 1986) which makes it a good indicator of the plant or bacterial food source of the consumers. Carbon is intermediate between N and S, increasing between 0.0 and 1.0 0/00 per trophic level. While overall isotopic composition of animals is controlled by diet, 197 both long-term and short-term diets are reflected in slow and fast tumover tissues (Peterson and Fry 1987). r3C, Stable isotopes, such as'oS and which provide source information, may be used to identiff different stocks of fish if the food sources differ in isotopic ratios, provided that the tumover time in the tissue examined is sufficiently slow so as to preserve such differences. The carbon isotopic composition of the whole body of an animal is directly related to its diet but the relationship of the carbon isotopic ratio of the tissue relative to that of the diet depends upon the type of tissue and the nature of the diet (DeNiro and Epstein 1978). The chemical and isotopic compositions of muscle, the tissue that I examined, reflect the diet that the fish has consumed over probably several months (Estep and Vigg i985). Four of the five samples that I examined for stable isotopes were from Arctic char that were returning from a summer of feeding in the sea at the time of capture. The similarity of ô'3C values (about - 2l0looto -24010ù for three of the four samples (Ellice, Halovik and Ekalluk rivers) provided little food source information that might contribute to stock discrimination among these samples. The fourth, from the Jayco River, showed a 0/ooto wider range in ôt3C values (about -19 -260loo), indicating that these char were feeding on a wider range of food source than the other three. I was not able to examine organisms at all trophic levels in the various food chains and thus could not determine the category of food item for each putative trophic level. However, I compared my data with that from Hobson and V/elch (1992) who studied the trophic relationships within a high Arctic marine food web. These authors 198 found that marine amphipods had a ôrsN range of about 10 0/00 rolz.5 o/oo while ôttN 0 0 5N values for marine fishes ranged from about I2.5 I 00 to 17 I oo. The ô' values for all four samples of sea run retumees that I examined provide some insight into stock differentiation based on the trophic level(s) at which they were feeding. The Arctic char fromtheHalovikRiver 1992andEkallukRiver lgg2samples(ôtsNof 90/ooto 12.50100) appeared to have been feeding on marine amphipods. Amphipods have been observed on a number of occasions in stomachs of Arctic char captured as they entered the Ekalluk River in autumn. The Arctic char in the sample from the Ellice River (ôtsN of I2.5 0looto 0/00) 15 appeared to have been feeding on marine fishes. The sample from the Jayco River 0lo'to 0/00) (ô'5N of 7.5 i5 appeared to have been feeding at two trophic levels, possibly including both amphipods and fish. The four samples were from widely separated geographic areas. These data suggest that Arctic char stocks in the Cambridge Bay area may frequent separate summer feeding grounds that offer different prey items. Tagging data (Dempson and Kristofferson 1987) indicate that Arctic char from the Halovik and Ekalluk rivers feed mostly in Wellington Bay and Jayco River Arctic char feed mostly in Albert Edward Bay. Ellice River Arctic char most likely feed in nearshore areas along the mainland coast. Welch and Parsons (1993) were able to identify a trophic hierarchy amongst five species of Pacific salmon along the west coast of Canada and Alaska, based on differences in õ'5N values. Chinook were at the top, followed by chum (Oncorhynchus. keta), coho, sockeye and pink (O. gorbuscha) salmon. They were also able to differentiate one stock of sockeye (Chilko) from four others (Adams, Early Stuart, Takla, Iliamna) 199 based on differences in ôrsN values. The Chilko stock had much lower ôr5N values than the other stocks. One explanation offered was that the Chilko sockeye stock feeds in regions of elevated nitrate levels. The alternate explanation is that the Chilko stock feeds at a lower trophic level. 0/ooto 0i00) The ô34S values (10 16 for most of the Jayco River Arctic char that appeared to be feeding on marine f,rsh were similar to those in the sample from Char Lake. However, the latter were spawners, captured in fresh water. Char Lake is one of the lakes that is very close to the sea, and the Sr prof,rles that were done on the otoliths of these char suggest that some may go to sea the summer prior to spawning. It is possible that the Arctic char spawners captured in Char Lake had gone to sea earlier in the sum.mer and had been feeding on marine fish in Albert Edward Bay. Homins As stated earlier, the two behavioral characteristics fundamental to the formation and maintenance of discrete stocks of fishes are homing of spawners to natal spawning sites and imprinting during early life history stages to the natal site (Honall 1981). Anadromous Arctic char in the Cambridge Bay area home to natal spawning grounds with a high degree of fidelity. This has manifested itself in the establishment of discrete spawning stocks that are readily distinguishable from geographically adjacent stocks on the basis of differences in morphometric measurements and, to a lesser extent, differences in meristic counts. There is a genetic component to this stock structuring as well. Reproductive isolation is evident, based on differences in allozyme frequencies between 200 some stocks. I present evidence of homing based on the direct relationship between strontium concentrations in the early growth zones of the otoliths of Arctic char spawners and the strontium concentrations in the surrounding waters of the spawning grounds where they were captured. The consistent similarity of the otolith strontium concentrations among all age groups within each sample of spawners provides evidence of philopatry over many generations. Therefore, I reject the null hypothesis that anadromous Arctic char in the Cambridge Bay area comprise a panmictic stock and accept the alternative hypothesis that anadromous Arctic char in this region are comprised of a number of discrete populations. Trace elements found in mineralized tissues of fishes have proven to be useful for stock identification (Edmonds et al. 1989, 199I,1992; Kalish 1990: Gunn et al. 1992; Campana and Gagne 1994).It is known that fish have the ability to concentrate chemical elements from the environment. Therefore, this approach is based on the premise that geographically distinct populations will reflect the chemical constituents of the water in which they reside (Simkiss 1974; Lapi and Mulligan 1981; Mulligan et al. 1987). The element strontium (Sr) has the same valence (2+) as calcium (Ca) and similar ionic radius (Ca, 0.99 Â, Sr, 1.13 A), hence it substitutes readily for calcium in the mineralization process, particularly in otoliths (Simkiss 1974;Radtke i989). The relative degree of the substitution of Sr for Ca depends largely on the relative concentrations of Ca and Sr in the ambient environment (Kalish i990). The uptake of strontium and its subsequent incorporation into hard tissues of fish has been confirmed by laboratory studies. Strontium can be incorporated into fish hard tissues through diet (Ophel and Judd 1968; Behrens Yamada et al. 1979; Beherns 201 Yamada and Mulligan 1982) and passively from the surrounding waters (Behrens Yamada and Mulliganl9ET; Schroder et al. 1995) and is localized in the area of the tissue that is being formed during uptake.. Schroder et al. (1995) demonstrated that detectable levels of strontium were taken up by newly emerged chum salmon fry when immersed in a solution of strontium chloride for as little as 24 h. Elevated Sr levels were detected by bulk Inductively Coupled Plasma Mass Spectrometry (ICPMS) in the otoliths (sagittae), vertebrae and opercula compared with control fish. The elemental composition of scales and vertebrae has been used with some success for stock identification (Lapi and Mulligan 1981; Gausen and Berg 19gg; Mulligan et al. 1983). Scales are useful structures to examine for trace element composition because they are relatively easy to obtain without killing the fish. However, Mugiya and Watabe (1977) summarize a number of studies that indicate that scales are resorbed under certain physiological conditions such as starvation (Ichikawa L953; Yamada 1956;), sexual maturation (Ouchi et aI.1972), and severe exhaustion due to spawning migration (Chrichton i935) and diet (Wallin 1957). According to Simkiss (1974) there is no resorption of otoliths although Mugiya and Uchimura (1989) were able to show evidence of calcium resorption in the otolith of the goldfish induced by anaerobic stress. They concluded that otolith resorption occurred in very rare cases only. Thus, the otolith is the preferred structure to use for stock identification purposes due to its relative resistance to resorption compared with scales and bone. The life history stage at which trace elements are incorporated into fish hard tissues has a direct bearing on the value of these elements for stock identification. A spawning ground may have a particular trace element "signature". This signature will be 202 most accurately reflected in the fish's hard tissue if it is incorporated from the spawning waters during the fish's early developmental stages (Campana et al. 1994). For this reason, Campana and Neilson (1985) recommend examination of the perinuclear region of the otolith. I examined both the nuclear and perinuclear regions of the otolith and, in most cases, found similar strontium concentrations between both regions. However, there \¡/ere some cases where the strontium concentrations in the nuclear region were higher compared with those in the adjacent growth regions. The reason for this appears to be related to the behaviour of the female just prior to spawning. Kalish (1990) has shown that the environment that the female occupies during vitellogenesis can affect the elemental composition of the nucleus of the otolith of its progeny, particularly with respect to strontium concentration. The process takes place during the formation of the oocyte in the female whereby the calcium moiety of vitellogenin, a phospholipoprotein-calcium complex yolk precursor (Mommsen and Walsh 1988), is substituted for strontium (Kalish 1990). Seawater contains about 8 ppm of Sr whereas fresh water contains about 0.1 ppm (Rosenthal et al. 1970) and, because the development of the ova in anadromous salmonids is virtually complete before these fish enter fresh water, their ova should contain higher levels of Sr than those of their nonanadromous counte{parts. Kalish (1990) found that the ova of anadromous Oncorhynchus mykiss contained five times more Sr than their nonanadromous conspecifics. The otolith nuclei are formed very early in the ontogeny of fishes and well before yolk utilization is complete (Brothers 1984; Kalish 1990). Therefore Kalish (1990) hypothesized that the higher levels of Sr in the yolk of anadromous females should 203 contribute to higher levels of Sr in the nuclei of the otoliths of their progeny compared with those of nonanadromous conspecif,rcs. He used an electron microprobe to examine transects across otoliths from the nucleus to the otolith edge and observed higher Sr/Ca ratios in the nuclei of sagittal otoliths of anadromous Salmo salar and S. trutta compared with nonanadromous Oncorhyncus mykiss and anadromous O. mykiss reared from freshwater broodstock. He confirmed this hypothesis in a controlled rearing experiment using sea-farmed and freshwater O. mykiss. Rieman et al. (1994), using a wavelength dispersive microprobe, found significantly higher Sr/Ca ratios in the otolith nuclei of anadromous sockeye salmon (O. nerka) compared with those of nonanadromous conspecifics. In both of the above studies, otolith Sr/Ca ratios in the growth zones formed subsequent to yolk absorption were lower than those observed in the nucleus. The Sr concentrations in these ratios were directly related to Sr concentrations in the freshwater spawning environment in the latter study (Rieman et al. 1994). The elevated levels of Sr in the nucleus of otoliths of some Arctic char that I observed in this study were similar to those observed by Kalish (1990) and Rieman et al. (1994) in the progeny of other anadromous salmonids. While most Arctic char in this study area do not go to sea the summer prior to spawning, I explain this elevated Sr concentration in the nucleus on the basis that the female parent went to sea for a short period of time during the summer prior to spawning. The greater frequency of occurrence of this Sr pattern in samples from spawning grounds close to the sea suggests that some Arctic char go to sea for a period of time during the summer prior to spawning, provided that the migration distance is relatively short. A feeding opportunity just prior to spawning may provide significant benefits to these char in terms of energy uptake and 204 may result in improved spawning success, and perhaps increased frequency of spawning events. Moore (1975a) observed both sexually mature male and female Arctic char in the sea near Baffin Island during the summer prior to spawning. Some Arctic char spawners have been observed in counting weirs as they returned from a surnmer trip to the sea (Kristofferson unpublished). Spawning events are energy dependent and the number of spawners in a given year appears to be related to feeding success during the summer of the previous year (Johnson 1980). For most Arctic char that do not go to sea the summer prior to spawning, the energy lost due to overwintering alone can be significant. Dutil (1986) observed that nonspawners from the Nauyuk Lake system, nearby my study area, experienced a30%;o loss in condition over the 1O-month overwintering period. Postspawners contained as much as 460/o less energy than nonspawners after spending two winters and a summer in fresh water. Postspawners were not able to recover this lost energy in one surnmer at sea, thus preventing them from spawning2 yr in succession (Dutil 1986). The Sr pattern in the otolith nucleus indicative of a summer feeding migration to the sea prior to spawning was seldom observed in Arctic char utilizing spawning grounds distant from the sea. This is likely related to energy as well. The cost of migrating to sea in terms of time and swimming energy expended may be more than the energy gained during a short feeding foray in the sea the summer prior to spawning. The direct relationship between the Sr concentration in the otolith nucleus and that of the waters of the respective spawning ground suggests that the female parents of these char spent some time on the spawning grounds prior to spawning. The Sr concentration in the early growth zones of the otolith, formed after the yolk sac was 205 depleted and exogenous feeding had begun, also reflected that of the respective spawning ground. At this stage of development, otolith Ca, and most likely Sr, originate from ions taken up by the gills (Simkiss 1974) and are thus a reflection of the Sr concentration of the surrounding environment. These young char are not very mobile and likely confine their movements to the spawning grounds themselves. Many of the Sr profiles of these spawners show a remarkable consistency in otolith Sr concentration from the nucleus almost until they make their first migration to the sea. This suggests that they remain for a relatively long time (years) in waters with a Sr concentration similar to that of the spawning grounds. The Sr concentrations in the early otolith growth zones of Arctic char that displayed elevated Sr concentrations in the nucleus were lower than those in the nucleus and matched the Sr concentrations in the waters of the spawning grounds. Therefore, a more reliable measure of the relationship between otolith Sr concentration and Sr concentration of waters of the spawning grounds can be made by examining the early otolith growth zones formed just after yolk absorption. Indeed, this is what I measured for all spawners in this study. The phenomenon of homing to natal spawning sites has great adaptive significance Qrlorthcote 1918; Horrall 1981) and is widespread among both freshwater and marine species (Leggett 1977).It (i) maximizes reproductive success by synchronizing the retum of mature individuals to proven spawning grounds that provide optimal conditions for egg and larval development; (2) regulates the number of adults using the spawning ground and thus prevents over- or under-utilization of a given area; and (3) facilitates reproductive isolation that contributes to the development of stock- specific adaptations to a particular habitat (Leggett 1977). Homing to natal spawning sites 206 for reproduction is well documented among salmonid fishes (Quinn 1993, and references therein). Homing of nonanadromous Arctic char to the natal site is also well documented (Alm 1951; LeCren and Kipling1963; Frost 1963;McCleave etal.1977). As Johnson (1980) points out, it seems unlikely that these nonmigratory char evolved the capacity to home since their isolation after the last glacial event. Most likely they inherited this behaviour from their anadromous ancestors. Homins has been documented in other closely related anadromous chars as well. Anadromous Dolly Varden are known to home with a high degree of fidelity to their natal stream to spawn (Armstrong 1974; Arrnstrong and Morrow 1980; Bernard et al. 1995). Straying can be def,rned as the migration of mature individuals to spawn in locations other than their natal site (Quinn 1993). Straying is important because it allows for the exploration of new environments (Johnson 1980) and the colonization of new habitats (Milner 1987; Milner and Bailey 1989). Straying can be influenced by events that affect the water quality of the home stream (Quinn 1993). Stream blockages, including very low water levels, are obvious barriers that can affect the spawners retum to natal spawning grounds. Pollution is another factor that can influence the degree of straying and there appears to be a positive correlation between the amount of straying and age, as has been observed in chinook salmon, Oncorhynchus tshawyfscåa (Quinn and Fresh 1984). Natural stream blockages in the study area do not appear to be common due to the low-lying nature of the surrounding topography. However, lowering water levels as a result of isostatic rebound over a long period of time, have the potential to increase the incidence of straying. No doubt this phenomenon has led to the coionization of new river systems since the retreat of the last glaciation. Pollution can be a problem, particularly in 207 some of the streams and rivers that are located near cortmunities. However, given the evidence of stock structuring presented here, it appears that straying among anadromous Arctic char stocks in the study area in recent time has not been significant. Two additional observations based on Sr concentrations in the early gro\ /th regions of otoliths of spawners are the incidence of nonanadromous Arctic char in the spawning sample, and the relative young age of spawners from two locations. First, nonanadromous Arctic char composed 71 percent of the Lady Pelly Lake spawners and 35 percent of the Anderson Bay Lake 1994 spawners. Access to the sea from both of these lakes is difficult, particularly in low water years. It is possible that both of these stocks are in the process of becoming landlocked. Second, few spalvners over the age of 14 years were observed in the samples from Halovik Lake 1993 and Mormt Pelly Lake 1993. This could be a reflection of stock-specific overexploitation, particularly for the Mount Pelly Lake stock, discussed later. Evidence of Mixing During Overwintering The Upstream Misration The fall upstream migration into freshwater is primarily a migration to suitable overwintering areas. However, it is also a spawning migration for those char that will spawn that autumn or the autumn of the following year. Diadromy, the movement of fishes between fresh and marine waters, evolved because the gain in fitness (reproductive success x survivorship) from using a second habitat minus the migration cost of moving between habitats exceeded the fitness of staying in only one habitat (Gross 1987). According to Gross (1987), the most important biological factor explaining the presence 208 and direction of such migrations is the relative availability of food in marine and freshwater habitats. In temperate zones, the sea is more productive than freshwaters (Gross 1987), thus anadromy is cornmon, particularly among the Salmonidae (McDowall 1987). Amongst the North American Salmonidae, Rounsefell (1958) classified the Arctic char as optionally anadromous and at the low end of the scale in degree of anadromy compared with the others. This is based not so much on salinity tolerance Q.{ilssen et al. I99l) as on the short Arctic summer. In the middle and high-Arctic, including the study area, Arctic char are limited to a marine residence of only 4-8 weeks (Johnson 1980; Dempson and Kristofferson 1987; Gulseth and Nilssen 2000). In the presence of ice, Arctic char are able to resist freezing down to a temperature of -0 .99 " C, and in the o absence of ice to a temperature of -1 .2 C (Fletcher et al. 1988). However, winter o seawater temperatures below -LJ C, such as those reported off the coast of Labrador CNutt and Coachman 1956), would likely be lethal to Arctic char. Therefore, they must return to fresh water to avoid freezing (Johnson 1980). Heterogeneitv in Genetics. Morphology and Otolith Strontium Concentrations in Samples from Upstream Migrations I present evidence that the upstream overwintering migrations of anadromous Arctic char in the study area are comprised of an admixture of char from different stocks. This evidence is based on genetics, morphometric heterogeneity and variation in the Sr concentrations of otolith nuclei of the returning migrants. Consequently, I reject the null hypothesis that the upstream migration of anadromous Arctic char in river systems within the study area is comprised of individuals from a single homogeneous population. I 209 accept the alternate hypothesis that this upstream migration is comprised of individuals from an admixture of more than one discrete population. The nonsatisfaction of the Castle-Hardy-Weinberg equilibrium when allozyme analysis was conducted on a sample of the upstream run in the Ekalluk River in 1992 is indicative of an admixture of stocks with different allele frequencies. Bernatchez et al. (1998) found nonsatisfaction of Castle-Hardy-V/einberg equilibrium of microsatellite gene frequencies within samples of upstream migrant anadromous Arctic char from a number of systems along the Labrador coast. They concluded that their samples represented an admixture of char from different populations that interchange among rivers for overwinterins. The 1992 Ekalluk River sample discussed above also showed considerable heterogeneity in meristic counts when compared with the other samples of the Ekalluk River upstream runs examined here. As well, evidence from the cluster analysis indicates that some samples of the upstream migrations I examined are comprised of Arctic char that differ in morphology. In many cases, the majority of the sample appears to form a morphologically similar cluster, although outliers are present in most of these samples. Most of these samples were taken in one or two days of fishing and could have consisted mostly of members of a single stock. This would suggest a temporal structure to the retum migration of each stock. However, samples from the upstream run taken over a period of 16-30 days (Freshwater Creek 1988, i991 ,1994) appear to be composed of a number of morphologically different groups. For example, the Freshwater Creek 1991 'When upstream migration contains three morphologically distinguishable clusters. these individual clusters \ /ere compared (discriminant fi,rnction analysis) with the 1992 and 210 1993 samples of spawners from this system, only one cluster appeared to be morphologically similar to the 1993 sample of spawners. The greater variation in Sr concentrations in the early growth region of the otoliths in the samples of retuming migrants is obvious when compared with that seen in the samples of spawners. This indicates that the upstream migrant sample is comprised of an admixture of Arctic char from spawning grounds that differed in water Sr concentration. Advantages of Mixine Durinq Overwinterinq The heterogeneity apparent in these upstream migrations is caused by a number of factors. The presence of at least three discrete stocks of anadromous Arctic char in the Ekalluk River system means that members of each of these stocks will participate in the annual upstream migration. Spawners will be obligated to return based on their homing behaviour. Their migration timing may overlap, resulting in a mixing of stocks during the run. This will take place in all rivers that are home to more than one spawning stock. Nonspawning Arctic char from each of these stocks will also be returning to fresh water and the timing of their migrations can overlap as well. Itinerants from other systems can also be apart of this upstream migration. During their limited time at sea, Arctic char movements are probably influenced by the spatial and temporal distribution of food items. This search for food might bring some char far from their home stream at the end of the surnmer. If they are not in condition to spawn the following year, the presence of a significant outflow of freshwater at ariver mouth, in addition to the scent and presence of conspecifics upstream may signal a safe haven (Johnson 1980). Entry into this system to 211 overwinter would save the char the energy of migrating to the home stream and perhaps the risk of being trapped in the sea. Arctic char tagged on the spawning ground in one river system have been recaptured overwintering in another river system in a later year (Kristofferson unpublished). Gyselman Q99$ found overall frdelity of tagged Arctic char to the Nauyuk Lake system to be low (53 %). However, ì.rpon closer examination, he found that there was a high-fidelity group that were previously tagged that had a return rate of 70-90 o/o and a low fidelity group, newly tagged, that had a return rate of 35-55%. He considered the high-fidelity group to be representative of the "true" Nauyuk Lake stock that reproduced in the system, and the low-fidelity group to be transients from other systems that were using Nauyuk Lake to overwinter because of its easy accessibility. Beddow et al. (199S) used radio-telemetry to study the migratory and reproductive behaviour of anadromous Arctic char in two adjacent river systems in northern Labrador. They found that spawning occurred in both river systems, but the spawners from the smaller river system (Reid Brook) migrated back to sea and then ascended the larger river system (Ikadlivik River) to overwinter within a single year. Apparently suitable overwintering habitat was lacking in the smaller river. A similar migratory pattem of spawning in a home river and overwintering in another system has been well documented for Dolly Varden (Armstrong 1974; Armstrong and Morrow 1980; Bernard et al. 1995). The apparent complex and variable migratory behaviour of anadromous Arctic char appears to be an evolutionary adaptation for maximizing habitat utilization and survival in a harsh environment (Johnson 1980). Homing optimizes reproductive success 212 and overwintering in a convenient but proven system can optimize energy uptake during summer feeding forays in the sea. Population Richness of Anadromous Arctic char The memberlvagrarfi hypothesis formulated by Sinclair and Iles (1988) provides a framework for studying the role of ecological processes involved in establishing spatial pattems of abundance in aquatic species. Four aspects of populations considered are pattern, richness, absolute abundance, and temporal variability. One prediction of the hypothesis is that population richness of a given species will depend upon the number of environmental settings available to the species to effect closure of the life cycle. Thus, anadromous fish species that home to a natal stream for spawning and in which eggs and juveniles rear, should be composed of numerous populations determined by the number of rivers available (Bernatchez et al. 1998). Indeed, this has been proven for species of the genus Salmo and Oncorhynchus (Davidson et al. 1989; Sinclair and Iles 1988). According to Sinclair and Iles (i988), three observations are considered important. The first is that homing to specific river systems has been convincingly demonstrated. The second is that egg and larval phases are completed within specific river systems themselves. The third observation is that there is extensive mixing of the juvenile and adult phases of the life history. Bernatchez et al. (i998) were reluctant to consider anadromous Arctic char as population rich because of their complex migration patterns and the lack of convincing evidence of homing to natal spawning grounds. They did, however, conclude that genetically distinct populations existed on a microgeographic scale. ¿ t.J I have presented convincing evidence of homing of anadromous Arctic char to natal spawning sites, as well as evidence that eggs and larval stages are compieted within a river system, based on the Sr concentrations within the early growth zones of otoliths. Therefore, I conclude that, based on the member/vagrant hypothesis, anadromous Arctic char is a population rich species, with the number of populations not only based on the number of river systems, but also on the number of suitable spawning sites within those river systems. This information must now be used to advantage for protecting and preserving this valuable resource. The genetic diversity of Arctic char is contained within the aggregate of all the individual populations that exist. As stated earlier, human-induced threats to the genetic diversity of Arctic char within the study area and throughout its Canadian distribution include excessive harvest and habitat destruction. Although habitat destruction appears to be localized near communities and is presently not widespread, environmental degradation resulting from mining and oil and gas exploration is a constant threat. However, the most significant threat to this species at present is excessive harvest. What follows is a suggested management approach that should be considered for the management of this valuable resource within the study area. Implications for Management The Arctic char is an excellent food source. Inuit populations are increasing and so is the demand for more Arctic char to meet subsistence needs. Economic opportunities are few in the Arctic and Arctic char fisheries, both commercial and sport, offer the promise of economic gain if they can be developed. These factors are contributing to an increased demand to harvest more Arctic char. However. the Arctic char cannot sustain 214 heavy exploitation because of its relatively slow growth, low fecundity and infrequent spawning events (Scott and Crossman 1973; Johnson 1980). Therefore, it must be managed very carefully. I discuss two management approaches that have been applied to Arctic char fisheries in the study area, and suggest a third management approach for future consideration. The first management approach is the traditional one employed by the Inuit prior to contact with European Americans. The second is the conventional fishery management approach employed by government during the development of commercial fisheries starting in the early 1960's. The third is an adaptive management approach that can be implemented under the legislated comanagement that now exists in the study area. Traditional Management The Arctic is a harsh environment, with long cold winters, short cool summers and a general paucity of food resources. Human inhabitants had to utilize adaptive processes and survival strategies to ensure their existence over the long term (Balikci 1968). As an example, the Inuit of Pelly Bay, formerly called the "Netsilik Eskimos", followed an annual migration circuit. In winter they relied on seals out on the sea ice. In summer they moved inland, harvesting seals along shore, and occasionally hunting caribou. In early autumn they fished for Arctic char using the stone weir or "saputit". In late autumn the Netsilik fished for char through the thin river ice. In winter, they moved again onto the sea ice to pursue the seal (Balikci 1968). The Arctic char was a very important food source and most harvesting took place during the autumn upstream migrations. In areas where Arctic char were abundant, starvation was rare (Balikci 1980). The Inuit of my study area, formerly called "Copper Eskimos", had a seasonal economic 215 cycle identical to that of the Netsilik (Damas 1968). Survival required that critical decisions had to be made to relocate if food sources went into decline in any particular area. The Inuit had accumulated a great deal of ecological and environmental expertise on a local level that provided them with a basis for this decision-making (Riedlinger and Berkes 2001). An excellent example of the traditional fishery management approach that aboriginal peoples have employed is described by Berkes (1999). He observed that the Chisasibi fishers, Cree Indians of James Bay, had developed an effective fishery management practice for lake whitef,rsh (Coregonus clupeaformis) and cisco (C. artedi) with three essential components. The first was to concentrate fishing on aggregations of fish, the second was to pulse fish intensively for a time and then move on, and the third was to harvest a range of sizes of fish. This allowed them to maximize the return for their effort by fishing concentrations of fish at the start. Catching a range of sizes of fìsh instead of concentrating on the large (reproductive) ones would allow escapement of spawners to ensure perpetuation of the stock(s). Moving on to other fishing locations when catch per unit of effort declined had the benef,rcial effect of relieving fishing pressure on a stock and allowing it to recover so that it could be fished again in the future. All three components were driven by the fishers' finely tuned ability to detect a decline in catch per unit of effort in their fisheries. They used this as an indicator of when to move on. The Inuit have practiced similar management methods to the Cree fishers discussed above. By fishing for Arctic char at the "saputit" during the autumn upstream migration, they maximized their return for effort because Ar"ii" char were present in ¿to great abundance in the upstream migration and were very vulnerable to capture in the shallow Arctic rivers. The char were also in prime condition after a summer of feeding in the sea and thus presented an ideal energy-rich food source. Arctic char ofa variety of sizes were captured (Balikci 1980), thus allowing escapement of some of the potential spawners. By using a highly tuned ability to detect declines in resource abundance, they would relocate to other systems before the resource was lost to them. This management approach ensured their survival up to the time of regular contact with European- Americans. Starvation is a strong selection pressure against less effective management practices. Traditional management, as summarized by Berkes et al. (1998), is adapted to the local area and resource users themselves are the "managers". Aliocation decisions are not made individually and compliance is by social sanctions. This system tends to have a large moral and ethical context and there is no separation between nature and culture. Knowledge is primarily qualitative and data gathering is diachronic (long time-series of local information). However, examples exist where traditional managers incorporate quantitative thinking and collect synchronic (simuitaneously observed) data. The Inuit of the Cambridge Bay area lived the traditional way of life of following food sources throughout the seasons until about 1946147. The construction of the L.O.R.A.N. station at Cambridge Bay at that time served to create a wage economy (see INTRODUCTION), which led to a concentration of Inuit in the settlement and a significant change from the traditional way of life. This event coincided with a decline in the market for fox furs so relatives of those employed drifted into Cambridge Bay for extended visits. This led to a further concentration of people in the community, and more 217 or less meant an end to their traditional lifestyle of living off the land (Abrahamson 1964). Conventional Management Conventional management, in contrast to traditional management, is based almost exclusively on scientific information and methods. Data are primarily quantitative and synchronic. Conventional management takes a reductionist approach to the resource and ecological complexities and uncertainties are often ignored. Resource managers are not resource users and allocation decisions are made at a distance from the community. This has led managers in the direction of tighter govemment controls over fisheries, which, over time, has often become unworkable (Berkes et al. 2001a). The conventional management approach was applied to the developing commercial fishery for Arctic char in the Cambridge Bay area. Government established fishing areas, a harvest limit or quota, fishing seasons and, ultimately, a minimum mesh size limit (139 mm) for gillnets used (Barlishen and'Webber 1973; Iftistofferson and Carder 1980; Kristofferson et al. 1984). There were no regulations limiting the subsistence harvest. The Arctic char resource in nearby Freshwater Creek was once abundant, which was why Inuit gathered seasonally at this "fair fishing place"(see INTRODUCTION). However, the concentration of Inuit in the settlement of Cambridge Bay meant increased fishing pressure to meet the subsistence needs of a growing population. In 1961, when the fishing co-operative \ilas formed to begin the commercial exploitation of Arctic char in the area, the first commercial fishery took place at Freshwater Creek. However, the Freshwater Creek Arctic char fishery was already showing signs of serious depletion 218 (Barlishen and Webber 1973) so the commercial fishery was relocated to the Ekaliuk River in L962 (Abrahamson 1964). At the outset, an annual quota of 18 000 kg was allocated to the Ekalluk River commercial fishery (Barlishen and Webber 1973). This river-specific quota remained in effect until 1967 when area fishers petitioned the federal government for an area quota for Wellington Bay. The intention was to allow commercial fishing to take place at the Lauchlan, Halovik and Paliryuak rivers that flow into Wellington Bay, as well at the Ekalluk River. An area quota of 46 000 kg was subsequently allocated to Wellington Bay. The economic constraints of developing a commercial fishery in this area were severe. Float-equipped aircraft were used to transport the catch from the fishing sites to Cambridge Bay and the frozen product was flown to markets in the south. In order to make a profit, fishers had to maximize the harvest and minimize the overhead. This led to a concentration of fishine effort at the Ekalluk River from 1967 to 1969. The result was a serious decline in the average size of Arctic char in the catch at Ekalluk River by 1969. The average weight of Arctic char taken in the Ekalluk River commercial fishery in 1963 was 3.9 kg. This had dropped to 1.4 kg by 1969. Consequently, the commercial fishery at the Ekalluk River was closed inI9l0. Following the closure of the Ekalluk River commercial fishery, river-specific quotas were put in effect and remain so to the present. This was based on the assumption that each river supported a discrete stock of Arctic char (Kristofferson et al. 1984). Gilinets, with a minimum mesh size of 139 mm still predominate the fishery, but a weir has been used periodically at three sites (Jayco, Ekalluk and Halovik rivers). There is no minimum size limit for Arctic char taken in the weir, although experience has shown that 219 the larger char are selected. These river fisheries appear to have been sustained over the years. However, in light of the results of this study, the Arctic char resource, on a stock by stock basis, might well have been utilized in a less-than-effective manner. This study has revealed that discrete stocks of Arctic char inhabit individual river systems in the Cambridge Bay area. This information supports the current river-specific harvest limits. However, this study has also revealed that multiple stocks of Arctic char spawn and overwinter within individual river systems. Therefore, upstream migrations are comprised of an admixture of Arctic char from the different resident stocks, as well as itinerant Arctic char from other river systems that migrate in only for overwintering purposes. The present conventional management approach is based on the assumption that the fishery is targeting a homogeneous stock at each fishing site. Random samples are taken each year from the commercial harvest that is carried out on these upstream migrations. Length and age data gathered over successive years are examined arurually to determine the response of the stock to certain harvest levels. These random samples likely have no biological meaning because the harvest is comprised of Arctic char from more than one stock and the proportional contribution of each stock to the fishery is unknown. Such data would not be sensitive to a decline of smaller. more vulnerable stocks and larger stocks could be harvested at less than optimal levels. Thus, utilizing these data for monitoring and modeling purposes is likely to give spurious results. Clearly, there is a need to manage these Arctic char fisheries as mixed-stock fisheries. A number of techniques have been used to estimate stock composition in the conventional management of mixed-stock fisheries. Examples of these techniques utilize stock differences based on morphology (Messinger and Bilton I974; Cook T982; 220 Fownier et al. 1984; Friedland and Reddin 1994), enzyme electrophoresis (Utter and Ryman 1993), mitochondrial DNA (Bermingham et al. 1991) and nuclear DNA (Galvin et al. 1995). These and other techniques should be investigated in terms of their usefulness for managing mixed-stock Arctic char fisheries in the study area. However, even when this is done, the current conventional management strategy alone will likely not deal adequately with this increased biological complexity and uncertainty. Comanagement Fisheries need to be managed on a small ecological scale taking into account local ecological factors such as habitat and local populations that are central to the health ofthe whole ecosystem. Fisheries management needs to be designed to fit this smaller scale by allowing resource users to take more responsibility for management and by utilizing their local knowledge of the resource (Berkes et al. 2001a). This can be accomplished through comanagement. Comanagement has been defined as a sharing of power and responsibility between the state and resource users in the management of natural resources (Pinkerton 1989). Comanagement as a process is flexible and participatory and provides a forum for rule making, conflict management, power sharing, leadership, dialogue, decision making, negotiation, knowledge generation and sharing, learning and development among resource users, stakeholders and government (Berkes et al. 2001a). In contrast to the conventional management approach that relies almost exclusively on scientific information and methods, and the traditional management approach that fails to take into account ecological complexities, comanagement combines the benefits of these two systems while largely eliminating the shortcomings of both. Comanagement allows 221 passing of responsibilities to resource users who then become accountable for their decisions. It utilizes fishers' local knowledge so that they become active participants in the development of management plans. Today in Canada, almost all of the Arctic char resource is found within the Nunavut Territory and the Inuvialuit Settlement Region of the Northwest Territories. The settlement of land claims in these areas formalized Íesource comanagement (Berkes et al. 2001b). The details of sharing ofjurisdiction for fisheries management can be found in specific sections of the Nunavut Land Claims Agreement (1993) and the Inuvialuit Final Agreement (1984). Well beforethe Nunavut Land Claims Agreement came into effect in 1993, a form of comanagement developed between the Govemment of Canada, Department of Fisheries and Oceans (DFO), and the residents of Cambridge Bay. During the late i970's and early i980's, DFO staff used a weir to enumerate the upstream migration of Arctic char at various commercial fishing sites in the Cambridge Bay area. Local Inuit were hired to assist in these projects and became familiar with this counting technique. Presentations of the results of these projects to community members contributed to a better understanding of what could be accomplished with this technique. Community members were well aware of the dwindling Arctic char resource in the nearby Freshwater Creek. Through the local Ekøluktutiak Hunters and Trappers Association (now called Hunters and Trappers Organization), they approached DFO with a request to enumerate the upstream migration of Arctic char in Freshwater Creek as a f,rrst step towards rehabilitation of the stock. DFO complied with this request and the upstream migration was enumerated by weir in 1982. This included a tagging program to determine the level 222 ofexploitation, harvest by fishery (recreational, subsistence), and the seasonal distribution of the Arctic char of Freshwater Creek. The 1982 weir project counted 9 961 Arctic char in the upstream migration (McGowan and Low 1992) and 1983 returns on the 808 Arctic char tagged in i982 revealed an exploitation rate in excess of 12 Yo. A study at nearby Nauyuk Lake (Johnson 19S0) indicated that this was excessive for Arctic char stocks in the area. The estimated total harvest in 1983 was just under 2 000 Arctic char. A creel census taken in 1983 (Carder I99l), combined with tag returns from the various fisheries revealed that about 46 o/o of the harvest was taken by the recreational fishery, 50 % by the subsistence fishery, and 4 %oby the commercial fishery. In the following years, 86 %o of all tag recoveries (1.{: 163) were made in Freshwater Creek, the sea near Cambridge Bay, or nearby Greiner Lake. The small number of Arctic char counted in the 1982 assessment convinced the residents of Cambridge Bay to develop a recovery plan for the Freshwater Creek Arctic char stock. Although it took time to implement, it appears to have been somewhat successful. Following is a summary of the comanagement steps taken by the government and the community in this regard: Government Community Weir count 1982 (9 961) Moratorium on subsistence gillnets (1988) Tagging program 1982 (1.{:808) Door-to-door harvest survey (1992,93,94) Creel census 1983 Weir count i98S (36 933) Community monitoring to comply with moratorium on eillnets 223 Reduce recreational limit (1 char daily) Continue dialogue with DFO r99l Weir count i991 (39 559) Continue dialogue with DFO Weir count 1994 (26150) Concem by community on lower count The results of the tagging study revealed that both the recreational and subsistence fisheries were targeting the Freshwater Creek Arctic char stock. This provided information to the community and govemment that there was a need to reduce the harvest of both fisheries. The government responded by reducing the catch and possession limit for nonnative fishers and the community implemented a ban on subsistence gillnet fishing. The locations where tagged char were captured provided the information needed to delineate the area where fishing pressure had to be reduced. The periodic counts of the upstream migration and the increase in migrant char observed in these counts provided information to community residents that their recovery program appeared to be successful. The periodic monitoring of the harvest provided evidence of compliance with the fishing restrictions. The experience described above has shown that by working together, govemment and the community of Cambridge Bay were able to accomplish what has been interpreted as a recovery of the Freshwater Creek Arctic char stock. In terms of empowerment, govemment had the authority to reduce daily catch and possession limits for non-native fishers from 4 Arctic char daily andT in possession to 1 daily. Although government had no regulations to limit the subsistence fishery, the community put the moratorium on subsistence gillnetting into effect and ensured aaÀ compliance through community sanctions. As a footnote, although the number of Arctic char counted in the 1994 upstream migration was less than that counted in 1991, the average size of char in the run had increased by 1994 as had the proportion of char of reproductive size. Clearly, comanagement is not a new concept to the residents of Cambridge Bay. The legislated comanagement put in effect in i993 by the Nunavut Land Claims Agreement, has provided the Inuit with government legislation and policy necessary to establish legal rights and authority frameworks for the use of natural resources including fisheries. This is critical if comanagement is to be successful (Pomeroy and Berkes 1997, Berkes et al. 200ia). The advantages of comanagement are many, as outlined by Berkes et al. (2001a). They include a more open and transparent process which is often more economical than centralized systems. Moreover, comanagement is adaptive, allowing participants to adjust their activities based on results obtained and lessons learned. Communitv members understand their own situations better than outsiders do and can devise and administer regulatory mechanisms that are often more appropriate than those imposed by external regulations. Most important, comanagement allows for the maximum use of indigenous knowledge and expertise as it applies to the resource in question. This knowledge can complement and strengthen scientific information gathering and interpretation as it appiies to management. Community involvement gives fishers a sense of ownership that often translates into greater compliance with management measures over the long term. 225 Indigenous knowledge can and does play a vital roie in effective fishery management where and when it is recognized. Berkes (1998) provides an operational definition of Traditional Ecological Knowledge QEK) as it is often called. It is " a cumulative body of lcnowledge, practice and belief, evolving by adaptive processes and handed down through the generations by cultural transmi.ssion, about the relationships of tiving beings (including humans) with one another and with their environment. " I would not have been able to conduct this study if it had not been for the traditional ecological knowledge that the fishers of Cambridge Bay so willingly supplied me with. At the outset, I was faced with a vast area of lakes and streams, and had only a map and a vague idea of where I might locate the many spawning grounds of the Arctic char that are a critical part of this study. After explaining the need to locate the spawning grounds to these fishers, I was shown on a map where to find them and in a number of cases, I was led directly to them. I have no doubt that a great deal of additional information of this type will be made available in future if fishers are given the chance to share it. The comanagement approach provides the opportunity to significantly improve upon the conventional fishery management approach that has been applied to this fishery. Adaptive Management under Comanagement Adaptive management is a relatively new management approach that has developed out of concem with practical problems of fishery and wildlife management (Holling 1978). As Berkes et al. (2001a) point out, adaptive management provides an opporhrnity to learn from successes and failures but it also relies on systematic feedback learning. It utilizes common-sense logic that emphasizes leaming-by-doing and it 226 eliminates the barrier between research and management. It has the advantage of systematic experimentation and the incorporation of scientific research into the overall management scheme. Adaptive management can be viewed as a rediscovery of traditional systems of knowledge and management. Although there are differences between the two, adaptive management is, in a sense, the scientific analogue of traditional ecological knowledge because it integrates uncertainty into management strategies and it emphasizes practices that confer resilience (Berkes et al. 2000). Adaptive and conventional management of resources differ primarily in the techniques of scientific methodology (McDonald 1988). Conventional resource managers attempt to reduce complex relationships occurring in harvesting systems to simplif,red associations. They also accumulate large quantities of data that form the basis of conservative policies until a better biological understanding is achieved. Adaptive managers, on the other hand, recognize that complex ecological relationships exist and that they do not fully understand them. They then attempt to identifu key relationships that can provide them with a measure of how the resource responds to various management practices. While both management approaches recognize the need for renewable resource management in general, they differ in their perception of the role of biological uncertainty (McDonald 1988). The conventional approach assumes that biological uncertainty is small and can be resolved through careful modeling. The adaptive management approach recognizes the uncontrolled nature of ecological uncertainties and emphasizes the need to synthesize ideas, experience and experimentation to deal effectively with this uncertainty (Walters 1986). Walters (1986) outlines three cyclical phases in the adaptive management process: 227 1. Structural analysis and synthesis to identify a range of alternative management options. These must be consistent with historical experience but must also provide new opportunities for improved harvest over the long-term. Attempts are made at predictive modeling of major processes to gain a better understanding of uncertainties against which experience can be tested and expanded. These models are used as predictors of possible outcomes rather than as instruments of policy analysis and decision. 2. Key management indicators are developed systematically through the use of altemative models and basic management options identified in the first phase. This is done to gain consensus among participants about the range of future management scenarios from which optimum policies can be developed to account for existing uncertainties. This takes into account the effects that current decisions mieht have on uncertainties that future decision-makers will face. 3. Design and implementation of effective monitoring programs that will detect the response of a system to management intervention and allow it to adapt quickly before unexpected changes result in undue economic or social hardship. Comanagement is adaptive because it is based on a leaming process where information is shared among stakeholders. This leads to continuous modification and improvements in management (Berkes et al. 2001a). It is now up to the participants, government and the resource users, to ensure that comanagement is implemented effectively. I suggest the following outline for the implement of an adaptive management 228 process for comanagement of the Arctic char resource in the Cambridge Bay area. Headings are from McDonald (1988). Phase Imolementation Action Dialogue Conduct a community presentation of the results of this study to outline the problem. This will include a discussion of the conventional monagentent approach, identification of management goals and the needfor an alternative approach. Field Study and Analysis Identify the need to collect and analyze additional information to provide a better understanding of the biological relationships within the ecological system that relate to key questions posed by management goals. Traditional ecolo gical knowledge can be incorporated such as identification of additional spawning grounds within river systems. Develop methods to determine the relative contributions of dffirent stoclrs to a mixedfishery. Design of Alternative Explore alternative management options, suclt Management Actions as pulse fishing, use of weirs etc., that can be tested 229 within the range of predictive outcomes. Monitoring and Assessment Analyze management actions in relation to observed of Management Actions changes in the system and in relation to outcomes predictedby ecological theory. Identifu key indicators in the system ( index netting of spawning aggregations ) to ensure the quality of the monitoring system. Evaluation Determine likely impacts of alternative management options (modeling) inview of the dffirent approaches taken. Identifu key questions posed by the management options which initiates subsequent rounds of the adaptive management process. zJv CONCLUSIONS As stated previously, the Arctic char resource is very important to the Inuit of the Cambridge Bay area as well as to resource users in other regions of the coastal Arctic. This study has provided information that has revealed a level of complexity in stock structuring of anadromous Arctic char that was previously suspected but not proven. Discrete stocks exist both within and between river systems, and upstream migrations are composed of an admixture of these stocks. In order to preserve the genetic diversity of this species in Canada, and hence the continued availability of this resource to users in perpetuity, future management approaches must consider this. The conventional management approach as it has been applied to this fishery has proven to be inadequate. An adaptive management approach, implemented under the legislated comanagement that is now in effect throughout most of the distribution of Arctic char in Canada, offers a more effective way to preserve the Arctic char resource while simultaneously providing optimum socio-economic benefits to the resource users. It will provide an opportunity to combine traditional ecological knowledge with the results of scientific research that will ultimately lead to a better understanding of the biological complexities of this species. It will provide for management options to deal with ecological uncertainties that will undoubtedly be encountered over time. It will also provide users with the incentive to utilize this resource in the best manner possible because of their participatory role in its management. 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Hokkaido Univ. 1:202-207. ,"t APPENDD( I Discrimina¡t function a1a-lysis of morphomehic measurements of Arctic char from spawning aggregations taken in the pËmut Rt;;däì- ruay pelty Lake, wishbone Lake and Ferguson Lake. sexuar ¿im"rpil;;* evident in many morphometric measurements. Therefore, tlis anarysis *ïJurri.¿ out MaLES and FTMaLES. separately on The results are presented below separation and indicate that g,õup is evident when the sexes are compared individualt;ä;ï;"ïili compared together (Fig. l5). rhey are I A O I.ADY c PELLY L. tr WISHBONE L. 4 E ^ FERGUSONL. 3 trl-oufrtr 2 ô¡ 1 q'3ï tr o o o€ oo o 0 Õ-Qo"Bf I É. a^4 -1 ¡A {-. o .^ o 4 ^t^^¡u¡^ o ^ a^ê -5 Aa MALES -6 -4 -2 Root 1 o t¡oypeu-yr-. tr WISHBONE L. a^^ A FERGUSONL. A ¡l--^ ^ 2 (! tr^^^^ tr Ë1o É.0 ]t"& tr tr tr Eitr o -1 tr T-o"# trtr_n .rooo tr u oo oot Etr Et o o FEMALES -þ 4 -2 2 Root 1 254 APPENDD( tr cluster analysis of morphometric measurements ofArctic char spawners taken from Halovik Lake and area in-1993. specimens were obtained from a number and upstream of llarovik of locations in {te (Fig 5) and poored t" r".. trr. sampre. Most ofthem appear to be morphorogica[y simiia¡ and fo.ln gorp * ,io*o in cluster H. croup appears to take place " at linkage dist¿nães u"¡".* 5 ;:Ti"t* and 6 in this stuãy Gig. Unweighted pair-group average Euclidean distances FgggFHHFg$FHF*ggËggg HALOVIK LAKE SPAWNERS 1993 34141 gääFäF 34177 34161 Ë.t¡¡Þ ã 34140 -Þ 34181 34170 isË ÊE.F 34160 34174 341 51 F$a$Ë$ 34172 Elo o - H O 34162 34175 ? eÉ FàiË 34148 34176 34180 fi åiË ã å 34179 c o 34144 J 34171 gågFtË - (D{ n 34145 mõ' È 341 53 gds= JÞFä1Ë È F 34150 o. o. x 34147 Rr¡ m 34173 5 0r. xi;FË,H ." Ø 7 Z -(, 34't54 34178 6-'q SËñssä ã 34146 d9 z 34152 BË FsäË m o t¡) an E n 34145 o år U' 34145 o- 34166 (O 34169 (D ÊÞoøtfãf,gHF 34165 341 39 FiãË ä 341 38 34164 g 34137 5'g'Ë Ë 34163 34136 ä ã €..? I 34168 34159 341 35 årËäË 341 58 34134 34167 åFFä$ õ H,rn 34142 (D Fe ral Ii 341 33 qE6 E