Canadian Manuscript Report

ofFisheries and Aquatic Sciences 2734

2005

EXPLORATORY INTERTIDAL BIVALVE SURVEYS

IN BRITISH COLUMBIA - 2004

by

G.B. Gillespie and N.F. Bourne

Fisheries and Oceans Canada

Science Branch, Pacific Region

P~cific Biological Station

Nanaimo, British Columbia V9T 6N7 11

© Her Majesty the Queen in Right ofCanada, 2005

Cat. No. Fs 97-4/2734E ISSN 0706-6473

Correct citation for this publication: .

Gillespie, G.B., and Bourne, N.F. 2005. Exploratory intertidal bivalve surveys in British Columbia - 2004. Can. Manuscr. Rep. Fish. Aquat. Sci. 2734: ix + 144 p. iii

TABLE OF CONTENTS

LIST OF TABLES IV

LIST OF FIGURES IV

LIST OF APPENDICES VII

ABSTRACT VIII

INTRODUCTION 1

METHODS 2

RESULTS 3

SMITH SOUND 3 RIVERS INLET 5 BURKE CHANNEL. '" .,. 8 SOUTH BENTINCK ARM 11 DEAN CHANNEL 12 ROSCOE INLET , 13 PORTBLACKNEY 15 TOLMIE CHANNEL 17 SPIDER ANCHORAGE , 20 KILDIDT SOUND 22 BROUGHTON STRAIT 24 DISCUSSION 25

BUTTER CLAMS 25 LITTLENECK CLAMS 25 MANILA CLAMS 26 VARNISH CLAMS 28 OLYMPIA OYSTERS 28 OTHER SPECIES 29 PLANKTON Tows 30 ACKNOWLEDGEMENTS 30

REFERENCES 30 iv

LIST OF TABLES

TABLE 1. LOCATION OF BEACHES SAMPLED DURING EXPLORATORY INTERTIDAL BIVALVE SURVEYS IN BRITISH COLUMBIA, JUNE 2004 , 33 TABLE 2. PHYSICAL DESCRIPTION OF BEACHES VISITED DURING EXPLORATORY INTERTIDAL BIVALVE SURVEYS IN BRITISH COLUMBIA, 2004 34 2 TABLE 3. CLAM DENSITIES (CLAMS M- ) BY SPECIES FROM EXPLORATORY INTERTIDAL BIVALVE SURVEYS IN BRITISH COLUMBIA, JUNE 2004 , 52 TABLE 4. DATE, TIME AND LOCATION OF PLANKTON TOWS CONDUCTED DURING EXPLORATORY INTERTIDAL BIVALVE SURVEYS, JUNE 2004 '" .. , 54

LIST OF FIGURES

FIGURE1. LANDINGS (T) AND VALUE ($CDN) OF INTERTIDAL CLAMS FROM BRITISH COLUMBIA COMMERCIAL FISHERIES, 1970-2001 55 FIGURE 2. LANDINGS OF MANILA CLAMS (T) FROM PACIFIC FISHERIES MANAGEMENT AREA 7,1992/1993 TO 2002/2003 SEASONS 56 FIGURE 3. GENERAL LOCATION OF EXPLORATORY INTERTIDAL BIVALVE SURVEYS IN BRITISH COLUMBIA, JUNE 2-19, 2004 57 FIGURE 4. LOCATIONS OF BEACHES SURVEYED IN SMITH SOUND, JUNE 3, 2004 58 FIGURE 5. LENGTH (TOP) AND AGE (BOTTOM) FREQUENCY DISTRffiUTIONS OF BUTTER CLAMS COLLECTED AT INDIAN ISLAND, SMITH SOUND, JUNE 3, 2004 59 FIGURE 6. LENGTH (TOP) AND AGE (BOTTOM) FREQUENCY DISTRffiUTIONS OF BUTTER CLAMS COLLECTED IN BROAD BAY, SMITH SOUND, JUNE 3, 2004 60 FIGURE 7. MEAN LENGTH-AT-ANNULUS OF BUTTER CLAMS COLLECTED AT INDIAN ISLAND, SMITH SOUND, JUNE 3, 2004 61 FIGURE 8. LENGTH (TOP) AND AGE (BOTTOM) FREQUENCY DISTRffiUTIONS OF LITTLENECK CLAMS COLLECTED AT INDIAN ISLAND, SMITH SOUND, JUNE 3, 2004 62 FIGURE 9. LENGTH (TOP) AND AGE (BOTTOM) FREQUENCY DISTRffiUTIONS OF LITTLENECK CLAMS COLLECTED IN BROAD BAY, SMITH SOUND, JUNE 3, 2004 63 FIGURE 10. LENGTH (TOP) AND AGE (BOTTOM) FREQUENCY DISTRffiUTIONS OF MANILA CLAMS COLLECTED AT INDIAN ISLAND, SMITH SOUND, JUNE 3, 2004 64 FIGURE 11. MEAN LENGTH-AT-ANNULUS OF LIVE MANILA CLAMS (TOP) AND DEAD MANILA SHELL (BOTTOM) COLLECTED AT INDIAN ISLAND, SMITH SOUND, JUNE 3, 2004 65 FIGURE 12. LENGTH (TOP) AND AGE (BOTTOM) FREQUENCY DISTRffiUTIONS OF SOFTSHELLS COLLECTED AT INDIAN ISLAND, SMITH SOUND, JUNE 3, 2004 66 FIGURE 13. LENGTH (TOP) AND AGE (BOTTOM) FREQUENCY DISTRffiUTIONS OF SOFTSHELLS COLLECTED IN BROAD BAY, SMITH SOUND, JUNE 3, 2004 67 FIGURE 14. MEAN LENGTH-AT-ANNULUS OF SOFTSHELLS COLLECTED AT INDIAN ISLAND (TOP PANEL) AND BROAD BAY (BOTTOM PANEL), SMITH SOUND, JUNE 3, 2004 68 FIGURE 15. LOCATION OF BEACHES SURVEYED IN RIVERS INLET, JUNE 4-5, 2004 69 FIGURE 16. LENGTH (TOP) AND AGE (BOTTOM) FREQUENCY DISTRffiUTIONS OF BUTTER CLAMS COLLECTED AT THE HEAD OF KLAQUABK CHANNEL, RIVERS INLET, JUNE 4,2004 70 FIGURE 17. LENGTH (TOP) AND AGE (BOTTOM) FREQUENCY DISTRffiUTIONS OF BUTTER CLAMS COLLECTED AT FURy ISLAND, RIVERS INLET, JUNE 4, 2004 71 FIGURE 18. LENGTH (TOP) AND AGE (BOTTOM) FREQUENCY DISTRffiUTIONS OF BUTTER CLAMS COLLECTED IN BIG FRYPANBAY,RIVERS INLET,JUNE4, 2004 72 FIGURE 19. MEAN LENGTH-AT-ANNULUS OF BUTTER CLAMS COLLECTED ATFURY ISLAND, RIVERS INLET, JUNE 4, 2004 73 FIGURE 20. LENGTH (TOP) AND AGE (BOTTOM) FREQUENCY DISTRffiUTIONS OF LITTLENECK CLAMS COLLECTED AT THE HEAD OF KLAQUABK CHANNEL, RIVERS INLET, JUNE 4, 2004 74 v

FIGURE 21. LENGTH (TOP) AND AGE (BOTTOM) FREQUENCY DISTRIDUTIONS OF LITTLENECK CLAMS COLLECTED AT FuRY ISLAND, RIVERS INLET, JUNE 4, 2004 75 FIGURE 22. LENGTH (TOP) AND AGE (BOTTOM) FREQUENCY DISTRIDUTIONS OF LITTLENECK CLAMS COLLECTED IN BIG FRYPAN BAY, RIVERS INLET, JUNE 4, 2004 76 FIGURE 23. MEAN LENGTH-AT-ANNULUS OF LITTLENECK CLAMS COLLECTED AT FURY ISLAND, RIVERS INLET, JUNE 4,2004 77 FIGURE 24. LENGTH (TOP) AND AGE (BOTTOM) FREQUENCY DISTRIDUTIONS OF SOFrSHELLS COLLECTED AT THE HEAD OFKLAQUAEK CHANNEL, RIVERS INLET, JUNE 4, 2004 78 FIGURE 25. MEAN LENGTH-AT-ANNULUS OF SOFrSHELLS COLLECTED AT THE HEAD OF KLAQUAEK CHANNEL, RIVERS INLET, JUNE 4, 2004 79 FIGURE 26. HEIGHT (TOP) AND AGE (BOTTOM) FREQUENCY DISTRIDUTIONS OF COCKLES COLLECTED AT FURy ISLAND, RIVERS INLET, JUNE 4, 2004 80 FIGURE27. MEAN HEIGHT-AT-ANNULUS OF COCKLES COLLECTED AT FuRY ISLAND, RIVERS INLET,JUNE4, 2004 81 FIGURE 28. LOCATION OF BEACHES SURVEYED IN BURKE CHANNEL, JUNE 6, 2004 82 FIGURE 29. LENGTH (TOP) AND AGE (BOTTOM) FREQUENCY DISTRIDUTIONS OF BUTTER CLAMS COLLECTED AT EDMUND POINT, BURKE CHANNEL, JUNE 6, 2004 83 FIGURE 30. LENGTH (TOP) AND AGE (BOTTOM) FREQUENCY DISTRIDUTIONS OF BUTTER CLAMS COLLECTED IN FOUGNER BAY, BURKE CHANNEL, JUNE 4, 2004 84 FIGURE'31. LENGTH (TOP) AND AGE (BOTTOM) FREQUENCY DISTRIDUTIONS OF BUTTER CLAMS COLLECTED AT KING ISLAND 2, BURKE CHANNEL, JUNE 4, 2004 85 FIGURE 32. MEAN LENGTH-AT-ANNULUS OF BUTTER CLAMS COLLECTED AT EDMUND POINT (TOP) AND IN FOUGNER BAY (BOTTOM), BURKE CHANNEL, JUNE 6, 2004 86 FIGURE 33. MEAN LENGTH-AT-ANNULUS OF BUTTER CLAMS COLLECTED AT KING ISLAND 1 (TOP) AND KING ISLAND 2 (BOTTOM), BURKE CHANNEL, JUNE 6, 2004 87 FIGURE 34. LENGTH (TOP) AND AGE (BOTTOM) FREQUENCY DISTRIDUTIONS OF LITTLENECK CLAMS COLLECTED IN FOUGNER BAY, BURKE CHANNEL, JUNE 6, 2004 88 FIGURE 35. MEAN LENGTH-AT-ANNULUS OF DEAD MANILA CLAM SHELL COLLECTED AT EDMUND POINT, BURKE CHANNEL, JUNE 6, 2004 89 FIGURE 36. LOCATION OF BEACHES SURVEYED IN SOUTH BENTINCK ARM, JUNE 7, 2004 90 FIGURE 37. LENGTH (TOP) AND AGE (BOTTOM) FREQUENCY DISTRIDUTIONS OFBALTIC MACOMAS COLLECTED AT THE HEAD OF SOUTH BENTINCK ARM, JUNE 7, 2004 91 FIGURE 38. LENGTH FREQUENCY BY AGE CLASS OF BALTIC MACOMAS COLLECTED AT THE HEAD OF SOUTH BENTINCK ARM, JUNE 7,2004 92 FIGURE 39. LOCATION OF BEACHES SURVEYED IN DEAN CHANNEL, JUNE 8, 2004 93 FIGURE 40. LENGTH (TOP) AND AGE (BOTTOM) FREQUENCY DISTRIDUTIONS OFSOFrSHELLS COLLECTED IN ELCHO HARBOUR, DEAN CHANNEL, JUNE 8, 2004 94 FIGURE 41. MEAN LENGTH-AT-ANNULUS OF SOFrSHELLS COLLECTED IN ELCHO HARBOUR, DEAN CHANNEL, JUNE 8, 2004 95 FIGURE 42. LOCATION OF BEACHES SURVEYED IN ROSCOE INLET, JUNE 9,2004 96 FIGURE 43. LENGTH (TOP) AND AGE (BOTTOM) FREQUENCY DISTRIDUTIONS OF MANILA CLAMS COLLECTED IN RIPLEY BAY, ROSCOE INLET, JUNE 9, 2004 97 FIGURE 44. MEAN LENGTH-AT-ANNULUS OF MANILA CLAMS COLLECTED IN RIPLEY BAY (TOP PANEL) AND MANILA CLAM SHELLS COLLECTED IN CLATSE BAY (BOTTOM PANEL), ROSCOE INLET, JUNE 9,2004 98 FIGURE 45. LENGTH (TOP) AND AGE (BOTTOM) FREQUENCY DISTRIDUTIONS OFSOFrSHELLS COLLECTED IN SHACK BAY, ROSCOE INLET, JUNE 9, 2004 99 FIGURE 46. LENGTH (TOP) AND AGE (BOTTOM) FREQUENCY DISTRIDUTIONS OF SOFrSHELLS COLLECTED IN RIPLEY BAY, ROSCOE INLET, JUNE 9, 2004 100 FIGURE 47. MEAN LENGTH-AT-ANNULUS OF SOFrSHELLS COLLECTED IN SHACK BAY (TOP PANEL) AND RIPLEY BAY (BOTTOM PANEL), ROSCOE INLET, JUNE 9, 2004 101 FIGURE 48. LOCATION OF BEACHES SURVEYED IN PORTBLACKNEY, JUNE 14, 2004 102 FIGURE 49. LENGTH (TOP) AND AGE (BOTTOM) FREQUENCY DISTRIDUTIONS OF BUTTER CLAMS COLLECTED IN OLIVER COVE, PORT BLACKNEY, JUNE 14, 2004 103 FIGURE 50. MEAN LENGTH-AT-ANNULUS OF BUTTER CLAMS COLLECTED IN OLIVER COVE, PORT BLACKNEY, JUNE 14, 2004 104 FIGURE 51. LENGTH (TOP) AND AGE (BOTTOM) FREQUENCY DISTRIDUTIONS OF LITTLENECK CLAMS COLLECTED IN BOATINLET,PORTBLACKNEY,JUNE24, 2004 105 vi

FIGURE 52. LENGTH (TOP) AND AGE (BOTTOM) FREQUENCY DISTRffiUTIONS OF LITTLENECK CLAMS COLLECTED IN OLIVER COVE, PORT BLACKNEY, JUNE 14, 2004 , 106 FIGURE 53. LENGTH (TOP) AND AGE (BOTTOM) FREQUENCY DISTRffiUTIONS OF MANILA CLAMS COLLECTED IN BOAT INLET, PORTBLACKNEY, JUNE 14, 2004 107 FIGURE 54. LENGTH (TOP) AND AGE (BOTTOM) FREQUENCY DISTRffiUTIONS OF MANILA CLAMS COLLECTED IN PASSAGE COVE, PORT BLACKNEY, JUNE 14, 2004 108 FIGURE 55. LENGTH (TOP) AND AGE (BOTTOM) FREQUENCY DISTRffiUTIONS OF MANILA CLAMS COLLECTED IN OLIVER COVE,PORTBLACKNEY,JUNE 14,2004 109 FIGURE 56. MEAN LENGTH-AT-ANNULUS OF MANILA CLAMS COLLECTED IN BOAT INLET (TOP) AND PASSAGE COVE (BOTTOM), PORT BLACKNEY, JUNE 14, 2004 110 FIGURE 57. MEAN LENGTH-AT-ANNULUS OF MANILA CLAMS COLLECTED IN OLIVER COVE, PORT BLACKNEY, JUNE 14, 2004 111 FIGURE 58. LENGTH (TOP) AND AGE (BOTTOM) FREQUENCY DISTRffiUTIONS OF SOFTSHELLS COLLECTED IN PASSAGE COVE, PORT BLACKNEY, JUNE 14, 2004 112 FIGURE59. MEANLENGTH-AT-ANNULUS OFSOFTSHELLS COLLECTED IN PASSAGE COVE, PORTBLACKNEY,JUNE 14, 2004 113 FIGURE 60. LOCATION OF BEACHES SURVEYED IN TOLMIE CHANNEL, JUNE 15-16,2004 114 FIGURE 61. LENGTH (TOP) AND AGE (BOTTOM) FREQUENCY DISTRffiUTIONS OF BUTTER CLAMS COLLECTED IN . ALEXANDER INLET, TOLMIE CHANNEL, JUNE 15, 2004 115 FIGURE 62. LENGTH (TOP) AND AGE (BOTTOM) FREQUENCY DISTRffiUTIONS OF BUTTER CLAMS COLLECTED IN BROWN COVE, TOLMIE CHANNEL, JUNE 15, 2004 116 FIGURE 63. LENGTH (TOP) AND AGE (BOTTOM) FREQUENCY DISTRffiUTIONS OF BUTTER CLAMS COLLECTED AT TOLMIE CHANNEL 1, TOLMIE CHANNEL, JUNE 15, 2004 117 FIGURE 64. LENGTH (TOP) AND AGE (BOTTOM) FREQUENCY DISTRffiUTIONS OF BUTTER CLAMS COLLECTED AT TOLMIE CHANNEL 2, TOLMIE CHANNEL, JUNE 16, 2004 118 FIGURE 65. LENGTH (TOP) AND AGE (BOTTOM) FREQUENCY DISTRffiUTIONS OF BUTTER CLAMS COLLECTED AT FLAT POINT, TOLMIE CHANNEL, JUNE 16, 2004 119 FIGURE 66. MEAN LENGTH-AT-ANNULUS OF BUTTER CLAMS COLLECTED IN ALEXANDER INLET (TOP) AND BROWN COVE (BOTTOM) , TOLMIE CHANNEL, JUNE 15, 2004 120 FIGURE 67. MEAN LENGTH-AT-ANNULUS OF BUTTER CLAMS COLLECTED AT TOLMIE CHANNEL 1, TOLMIE CHANNEL, JUNE 15, 2004 121 FIGURE 68. MEAN LENGTH-AT-ANNULUS OF BUTTER CLAMS COLLECTED IN HIGH DENSITY AREAS (TOP) AND LOW DENSITY AREAS (BOTTOM) OF TOLMIE CHANNEL 2, TOLMIE CHANNEL, JUNE 16,2004 122 FIGURE 69. LENGTH (TOP) AND AGE (BOTTOM) FREQUENCY DISTRffiUTIONS OF LITTLENECK CLAMS COLLECTED IN ALEXANDER INLET, TOLMIE CHANNEL, JUNE 15,2004 123 FIGURE 70. LENGTH (TOP) AND AGE (BOTTOM) FREQUENCY DISTRffiUTIONS OF LITTLENECK CLAMS COLLECTED AT TOLMIE CHANNEL 1, TOLMIE CHANNEL, JUNE 15, 2004 124 FIGURE 71. LENGTH (TOP) AND AGE (BOTTOM) FREQUENCY DISTRffiUTIONS OF LITTLENECK CLAMS COLLECTED AT TOLMIE CHANNEL 2, TOLMIE CHANNEL, JUNE 16, 2004 125 FIGURE 72. LENGTH (TOP) AND AGE (BOTTOM) FREQUENCY DISTRffiUTIONS OF LITTLENECK CLAMS COLLECTED AT FLAT POINT, TOLMIECHANNEL,JUNE 16,2004 126 FIGURE 73. LOCATIONS OF BEACHES SURVEYED IN SPIDER ANCHORAGE, JUNE 17, 2004 127 FIGURE 74. LENGTH (TOP) AND AGE (BOTTOM) FREQUENCY DISTRffiUTIONS OF BUTTER CLAMS COLLECTED AT HURRICANE ISLAND 1, SPIDER CHANNEL, JUNE 17, 2004 128 FIGURE 75. LENGTH (TOP) AND AGE (BOTTOM) FREQUENCY DISTRffiUTIONS OF BUTTER CLAMS COLLECTED AT HURRICANE ISLAND 4, SPIDER ANCHORAGE, JUNE 17, 2004 129 FIGURE 76. MEAN LENGTH-AT-ANNULUS OF BUTTER CLAMS COLLECTED IN SPIDER ANCHORAGE, JUNE 17,2004.. 130 FIGURE 77. LENGTH (TOP) AND AGE (BOTTOM) FREQUENCY DISTRffiUTIONS OF LITTLENECK CLAMS COLLECTED AT HUNTER ISLAND, SPIDER ANCHORAGE, JUNE 17,2004 131 FIGURE 78. LENGTH (TOP) AND AGE (BOTTOM) FREQUENCY DISTRffiUTIONS OF MANILA CLAMS COLLECTED AT HUNTER ISLAND, SPIDER ANCHORAGE, JUNE 17, 2004 132 FIGURE 79. MEAN LENGTH-AT-ANNULUS OF MANILA CLAMS COLLECTED IN SPIDER ANCHORAGE, JUNE 17,2004. 133 FIGURE 80. LENGTH (TOP) AND AGE (BOTTOM) FREQUENCY DISTRffiUTIONS OF SOFTSHELLS COLLECTED AT HURRICANE ISLAND 1, SPIDER ANCHORAGE, JUNE 17, 2004 134 FIGURE 81. MEAN LENGTH-AT-ANNULUS OF SOFTSHELLS COLLECTED IN SPIDER ANCHORAGE, JUNE 17,2004 135 FIGURE 82. LOCATION OF BEACHES SURVEYED IN KILDIDT SOUND, JUNE 18, 2004 136 vii

FIGURE 83. LENGTH (TOP) AND AGE (BOTTOM) FREQUENCY DISTRffiUTIONS OF BUTTER CLAMS COLLECTED AT WATT BAY 1, JUNE 18, 2004 137 FIGURE 84. MEAN LENGTH-AT-ANNULUS OF BUTTER CLAMS COLLECTED AT WATT BAY 1, KILDIDTSOUND, JUNE 18, 2004 138 FIGURE 85. LENGTH (TOP) AND AGE (BOTTOM) FREQUENCY DISTRffiUTIONS OF LITTLENECK CLAMS COLLECTED AT WATT BAY 1, JUNE 18,2004 139 FIGURE 86. LENGTH (TOP) AND AGE (BOTTOM) FREQUENCY DISTRffiUTIONS OF MANILA CLAMS COLLECTED IN KILDIDT SOUND, JUNEI8, 2004 140 FIGURE 87. MEAN LENGTH-AT-ANNULUS OF MANILA CLAMS COLLECTED IN KILDIDTSOUND, JUNE 18,2004 141 FIGURE 88. LOCATION OF BEACH SURVEYED IN BROUGHTON STRAIT, JUNE 19, 2004 142

LIST OF APPENDICES

APPENDIX 1. COMMON AND SCIENTIFIC NAMES OF SPECIES RECORDED DURING EXPLORATORY INTERTIDAL BIVALVE . SURVEYS IN BRITISH COLUMBIA, JUNE 2004 143 APPENDIX 2. DATA COLLECTION FORM USED DURING EXPLORATORY INTERTIDAL BIVALVE SURVEYS IN BRITISH COLUMBIA, JUNE 2004 144 Vlll

ABSTRACT

Gillespie, G.B. and Bourne, N.F. 2005. Exploratory intertidal bivalve surveys in British Columbia - 2004. Can. Manuscr. Rep. Fish. Aquat. Sci.2734: ix + 144 p.

Results of exploratory intertidal clam surveys carried out in June 2004 to assess populations ofcommercially important clams, exotic varnish clams, Nuttallia obscurata, and native Olympia oysters, Ostrea conchaphila, on selected beaches in British Columbia (B.C.) are presented. These surveys were a continuation ofexploratory clam surveys begun in 1990 to assess intertidal clam resources in the North and Central Coasts. These surveys were expanded to include exploratory work to map dispersal ofthe exotic varnish clam, and to map distribution ofthe native Olympia oyster.

Manila clam populations were sparse in Smith Sound, Rivers filet, Spider Anchorage and Kildidt Sound. Manila clams were not found in Burke, Dean and Tolmie Channels, nor in South Bentinck Arm. Manila clams were present in Roscoe filet and abundant in Port Blackney. Growth ofManila clams was generally slow in the North Coast relative to South Coast populations.

Varnish clams were not found in the North Coast, other than a pair ofdead shells found at fidian Island in Smith Sound. This is the first evidence ofthis exotic species in the North Coast, and data accumulated to date suggest that the species is dispersing northward through Johnstone and Queen Charlotte Straits and could continue to spread northward.

Additional biological data were collected for littleneck and butter clams, softshells and cockles. Distribution and abundance data were collected incidentally for horse clams and macomas, and size, age and growth data were collected for a population ofBaltic macomas in South Bentinck Arm. Plankton tows done in most locations indicated low numbers ofbivalve larvae. IX

RESUME

Gillespie, G.B. and Bourne, N.F. 2005. Exploratory intertidal bivalve surveys III British Columbia - 2004. Can. Manuscr. Rep. Fish. Aquat. Sci.2734: ix + 144 p.

Nous presentons ici les resultats des re1eves exploratoires realises enjuin 2004 pour evaluer l'etat des populations d'especes commercialement importantes de bivalves fouisseurs intertidaux - palourdes, nuttallies obscures (Nuttallia obscurata) et huitres plates du Pacifique (Ostrea conchaphila), sur certaines plages de Colombie-Britannique. Ces releves prolongeaient les reieves exploratoires des bivalves commences en 1990 pour evaluer les ressources coquillieres Ie long de la cote Nord et de la cote centrale. Ces releves ont ete etendus pour inc1ure des travaux exploratoires visant acartographier la dispersion de la Nuttallie obscure et la distribution de I'Hultre plate du Pacifique.

.Les populations de palourdes japonaises etaient c1airsemees dans l'inlet Rivers et les baies Smith, Spider Anchorage et Kildidt. Aucune palourde japonaise n'a ete observee dans les passages Burke, Dean et Tolmie ni dans Ie bras South Bentinck. Le mollusque etait par contre present dans I'inlet Roscoe et abondant dans la baie Port Blackney. La croissance des palourdes japonaises etait generalement lente Ie long de la cote Nord par rapport aux taux observes sur la cote Sud.

Aucune nuttallie obscure n'a ete trouvee sur la cote Nord, mis apart une paire de coquille vide trouvee dans la baie Smith, sur I'lle Indian. II s'agit du premier signe de presence de cette espece exotique sur la cote Nord et les donnees recueillies ace jour indiquent que l'espece se repand actuellement vers Ie nord atravers les detroits de Johnstone et de la Reine-Charlotte et qu'elle pourrait continuer ase repandre dans cette direction.

Des donnees biologiques supplementaires ont ete recueillies pour la Palourde du Pacifique et la Palourde jaune, la Mye et la Coque europeenne. Des donnees de distribution et d'abondances ont ete recueillies en passant pour la Fausse-mactre et la Macoma tandis que des donnees sur la taille, l'age et la croissance ont egalement ete recueillies pour une population de macomas baltiques dans Ie bras South Bentinck. Sur la plupart des sites, les remorquages de plancton n'ont revele qu'un faible nombre de larves de bivalves. INTRODUCTION

The present survey was part of a program begun in 1990 to assess intertidal bivalve resources in British Columbia (Bourne and Cawdell1992; Bourne et at. 1994; Bourne and Heritage 1997; Heritage et at. 1998; Gillespie and Bourne 1998,2000, in press; Gillespie et at. 2004). Initially these surveys focused on studies of the dispersal and extent of populations of Manila clams, Venerupis philippinarum, in coastal waters of northern B.C., as this species has dominated commercial clam landings in B.C. since the early 1980's (Figure 1). One result of these surveys was the development of a commercial fishery for Manila clams in the Bella Bella area in 1992 that has continued to the present day with annual landings ranging from 25-115 t (Gillespie et at. 1999a, 200la; Figure 2).

Since the late 1990's these surveys have become more extensive and inclusive. Surveys have been extended to include other areas, including Queen Charlotte Strait, Johnstone Strait, the west coast of Vancouver Island and the Queen Charlotte Islands. The scope of the surveys has also been extended to include assessment of populations of species that are utilized in the present commercial fishery in B.C. or have potential in future fisheries. These species include; butter clams, Saxidomus giganteus, littleneck clams, Protothaca staminea, cockles, Clinocardium nuttallii, softshells, Mya arenaria, horse clams, Tresus capax, and the native Olympia oyster, Ostrea conchaphila. In recent years there has been increased interest by industry to harvest these species and this includes harvest in the North Coast. Iffisheries for these species develop in the North Coast, it is essential that sufficient biological information is available for efficient management of these resources.

In addition to collection of information on the above stocks, incidental information has been gathered on other species to add to our knowledge of the distribution and abundance of intertidal fauna in RC.! Of particular interest in recent surveys has been collection of information on the distribution and abundance of stocks of the varnish clam, Nuttallia obscurata, which was introduced into RC. in the late 1980's and has since spread rapidly northward (Gillespie et at. 1999b, 2001b).

The present survey took place from June 3-19,2004 and extended from Broughton Strait in the south to Tolmie Channel in the north. It included re-visiting some areas to determine if there had been pronounced changes in intertidal clam populations, particularly populations ofManila clams, along with surveys ofnew areas to assess if Manila clams were present, assess the state of such populations and to gather information on the extent and state of populati.ons of other clam species.

1 Common and scientific names for all species recorded are in Appendix 1. 2

METHODS

Methods used in the surveys have changed little since they began in 1990 and have been described previously (Bourne and Cawdell 1992; Bourne et ai. 1994; Bourne and Heritage 1997; Heritage et ai. 1998; Gillespie and Bourne 1998,2000). Beaches were selected for survey from charts, as well as from previous experience, DFO clam atlases (Harbo et ai. 1997), contract reports (Aquametrix Research and Axys Environmental Consulting 1997, Peacock et ai. 1998), information from Fisheries Officers and local inhabitants and from requests by industry. A guiding principal in this work has been to maximize the number of beaches explored during a tide, rather than survey one or two beaches in detail (fide Gillespie and Kronlund 1999). Results of these surveys give estimates of clam distribution and abundance in surveyed areas and not statistically rigorous stock estimates.

The exact location of each beach was determined from charts and by GPS. A brief survey was made of each beach visited to assess the presence or absence of intertidal clams and determine the area of the clam bearing part of the beach prior to sampling. Clam areas were estimated by digging exploratory holes to delimit clam distribution. Slope of the beach and substrate type were recorded. The high tide line was surveyed for drift shell of intertidal clams and large rocks which are used by birds to drop and break clams were examined for shell fragments. In the past, evidence of the presence of Manila clams has been determined with these latter assessment methods.

When aggregations of clams were found, quadrats of 0.25 m2 and 1.00 m2 were dug. Quadrats in the upper portion of the intertidal zone (0.25m2 targeting mainly on Manila clams and to a lesser extent on littleneck clams) were dug with a clam scraper to a depth of about 15 cm. Quadrats lower on the beach (1 m2 targeting mainly on butter clams and to a lesser extent on littleneck clams) were dug with a potato fork to a depth of about 35 cm. When Manila clams were present at very low abundance, quadrat size was expanded until sufficient clams for biological sampling were obtained (preferably more than 20 clams), or until no more Manilas could be found, and final quadrat size was estimated and recorded. In all cases, the dug substrate was reworked back into the quadrat through the fingers to detect clams missed when the quadrat was initially dug. All dug clams were washed, bagged and labeled for processing. Additional information was gathered on incidental species of invertebrates found on beaches and some specimens were collected for further identification.

Anew innovation for the present survey was the design and use of a beach reporting form (Appendix 2) that greatly facilitated collection of data and transfer of this information to the computer.

Total length of each clam (longest anterior-posterior length, TL) was measured to the nearest mm with vernier calipers. Shell height, from the umbo to the ventral shell margin, was measured for cockles. Ages were determined by counting annuli (Quayle and Bourne 1972). Length/height and age frequency distributions were determined and graphed. Length/height at annulus was measured for a representative sample of Manilas, 3 littlenecks, butters, softshells and cockles. This provided length/height and age distribution and growth rate information for these species in each area surveyed. Surface water temperature at a depth of 20 cm was recorded with a standard hand-held thermometer in each area. A five minute surface plankton tow using a 40 cm diameter frame and 70 p,m mesh was made in each area to determine the presence of any bivalve larvae.

RESULTS

Forty-three beaches were surveyed in 11 areas in 2004 (Table 1). The survey area extended from Broughton Strait in the south to Tolmie Channel in the north (Figure 3).

Smith Sound

Smith Sound opens onto Queen Charlotte Sound and extends northeast to the mouths of Smith and Boswell Inlets. Although partially protected by a number of islands near its mouth, there is usually a considerable swell from the open ocean and clam beaches are restricted to protected bays and channels.

Modest harvest of butter clams occurred in Smith Sound until the area was closed in the mid 1960's because of chronic low levels ofParalytic Shellfish Poisoning (PSP) in some North Coast butter clam populations (Quayle 1966). Smith Sound was surveyed in 1993; sampling focused on assessment of intertidal clams on beaches at the mouth of the sound (Bourne and Heritage 1997). At that time butter and littleneck clams were found in abundance on selected beaches and Manila clams were found on three beaches. Most Manila clams were large and growth was slow. Beach surveys conducted in 1996 (Aquametrix Research and Axys Environmental Consulting 1997) found Manila clams or shell at several beaches in Smith Sound and Smith and Boswell Inlets, but did not estimate densities or collect biological samples.

It was of interest to resurvey this area to determine if the population ofManila clams had increased since 1993 to the point where it could support commercial harvest. Another important focus of the survey was to determine if varnish clams had spread this far north.

Physical Description of Beaches .

Four beaches that were sampled in 1993 (Indian Island, Fly Basin, Broad Bay and the north side of Greaves Island) were surveyed in 2004 (Figure 4). Beaches 1,2,3, and 4 in 2004 were beaches 9, 6, 5 and 3 respectively in 1993 (Bourne and Heritage 1997). Broad Bay and Greaves Island were surveyed by Aquametrix Research and Axys Environmental Consulting (1997); their beach codes SC_013 and SC_011, respectively. 4

Area of these four beaches ranged in size from 0.5-3 ha, the clam bearing area from <0.1-2 ha (Table 2). Slopes of the four beaches were generally low. Substrate varied from sand-mud to sand-shell to sand-mud-clay with cobble and rock particularly at the high tide line and around the margin of some beaches. In general, the substrate was suitable clam habitat except at beach 4. Eelgrass, Zostera marina, was abundant at the lower edges of the beaches.

Bivalve Populations

Dead shells of butter, littleneck and Manila clams were found on all four beaches, along with shells of horse clams, cockles and softshells.

Bqtter Clams

In 1993, butter clams were abundant on two beaches and density of commercial size clams was as high as 152 clams m-2 and up to 100 clams m-2 for sublegal size clams. In the present survey, butter clams were again found to be abundant in suitable habitat on selected beaches and density was as high as 44 clams m-2 at Broad Bay (Table 3).

In the 1993 survey there was a wide range of sizes and ages of butter clams indicating good recruitment over a period of several years. In the present survey there was a preponderance of older clams at Indian Island (Figure 5) and of younger clams at Broad Bay (Figure 6). Growth was moderate and a shell length of 63 mm was attained in about 6.5 years (Figure 7).

Littleneck Clams

In past surveys, littleneck clams were the most abundant bivalve (in total number and mass) found in the intertial area. This situation probably existed in Smith Sound if sampling had targeted on this species. In thepresent survey, density ranged from 7-72 clams m-2 at Indian Island and 0-28 clams m- at Broad Bay (Table 3).

In 1993 there was a wide range of size and age with a preponderance of 4-6 year aIds. In the present survey there was a wide range in size and ages at Indian Island (Figure 8) but at Broad Bay all were 5-7 years of age (Figure 9).

Manila Clams

In 1993, Manila clams were modestly abundant and density was as high as 56 2 clam m- • There was a fairly wide size and age distribution, most were 4-7 years in age. In the present survey, evidence of Manila clams was found on all four beaches and density at Indian Island and Broad Bay ranged from 0-40 clams m-2 (Table 3). A single live Manila clam (32 mm TL, age 3) was found in scratches on Greaves Island North. At 5

Indian Island, ages ranged from 3-8 years (Figure 10). Growth was fairly rapid and a shell length of 38 mm was attained in about 3.5 years (Figure 11).

Manila clam populations in Smith Sound remain similar to what was found in 1993. Successful breeding is occurring and the population is maintaining itself, however, populations are too low to support commercial harvest.

Varnish Clams

A pair of dead varnish clam shells (31 mm TL, age 3) was found at Indian Island. The shells were still attached together by the ligament, the distinctive purple color inside the shells was faded and the periostracum was somewhat worn, particularly at the margins of the shells. It appeared that the clam died some time before, perhaps the previous summer.

Other Species

Softshells were found on all four beaches; at Broad Bay they occurred at a density of 72 clams m-2 (Table 3). Softshells collected at Indian Island (Figure 12) were relatively large and ranged in age from five to 11 years; those collected at Broad Bay (Figure 13) were smaller and ages were primarily between two and six years. Growth was moderate and they attained a shell length of 50 mm2 in about four years (Figure 14).

Although no horse clams or cockles were dug in the quadrats, either dead shells or live animals (both species of horse clams, T. capax and T. nuttallii) were found on all four beaches. Horse clams are undoubtedly common in suitable habitat.

A large California mussel was collected on the rocky saddle area of Broad Bay, and kellyclams and Arctic hiatella were found under rocks.

Other Observations

A five-minute surface plankton tow taken in Takush Harbour (Table 4) contained large numbers of bivalve larvae. These were primarily Mytilus larvae ranging from straight-hinge to eyed stages. Also observed were single specimens of hiatella, littleneck and softshelliarvae, all in the umbone stage. Surface water temperature offthe four beaches was 13-14°C (Table 2).

Rivers Inlet

Rivers Inlet opens onto Fitz Hugh Sound and although partially protected from Queen Charlotte Sound by Calvert Island and from Fitz Hugh Sound by Penrose, Ripon,

2 The legal size for softshells in commercial fisheries in Atlantic Canada is 50 mm total length. 6

Walbran and smaller associated islands, still experiences large swells in any adverse weather. Near the mouth of the Inlet, clam beaches are limited to smaller bays and narrow channels between the islands of the archipelago. Upper Rivers Inlet and the associated inlets of the system (Drainey, Hardy and Moses Inlets) are generally steep sided and clam beaches are either small pockets associated with small streams or large sand/silt beaches at the mouths of larger rivers.

Beaches at the mouth ofRivers Inlet were surveyed in 1991 and a brief survey was made of Goose Bay at the southern entrance to the Inlet in 1993 (Bourne et ai. 1994; Bourne and Heritage 1997). The main focus in both surveys was to determine the presence or absence of Manila clams. No live Manila clams or dead shells were found in the 1991 survey of areas at the mouth of the Inlet. In 1993, a pair of shells of a dead Manila clam was found in Goose Bay indicating the presence of the species in the area. Goose Bay was surveyed in 1996 (Aquametrix Research and Axys Environmental Consulting 1997, their beaches SC_046, SC_047 and SC_048); as was the beach at the head of Klaquaek Channel (their beach SC_073); no evidence of Manila clams was reported. They reported evidence of Manila clams from three beaches on the southern and western sides of Ripon Island (their beach codes SC_066, SC_069 and SC_070).

While the purpose of the present survey was to assess populations of all bivalves of commercial or potential commercial value, a particular focus was to determine if Manila clams were now present in the inlet and, if so, to assess their abundance.

Sampling was undertaken on two days, June 4 and 5. On June 4, five beaches at the mouth of the inlet were sampled (Klaquaek Channel, Penrose Island North, Fury Island, Big Frypan Bay and Taylor Bay; Figure 15), some of which had been surveyed in 1991 (Table 1). On June 5, two beaches at the head of the inlet (Kilbella Bay and the Whannock River estuary) were sampled.

Physical Description of Beaches

Some of the five beaches sampled at the mouth of the inlet were the same as sampled in 1991; beaches at the head of Klaquaek Channel and Penrose Island North were beaches 3 and 2 in the 1991 survey.

The five beaches at the mouth ofthe Sound ranged in size from 0.1-4.0 ha, while the estimated clam bearing area ranged from <0.1-3 ha (Table 2). Slope of the beaches varied from low to moderate and the substrate from mud to hard packed shell-sand to rocks and boulders.

The two beaches surveyed at the head of the Inlet were large and area ranged from 3.0 to >20 ha (Table 2). The substrate was generally packed sand with some wood debris (which smelled of HzS) and some rock. The entire area was poor habitat for bivalves. 7

Bivalve Populations

Although sampling focused on assessment of the presence or absence of Manila clams, quadrats were dug to assess butter and littleneck populations.

Butter Clams

Butter clams were abundant on beaches at the mouth of the inlet (Table 2). In plots dug at Klaquaek Channel and Fury Island, density ranged from 0-376 clams m-2 (Table 3). At Klaquaek Channel, shell length was 40-71 mm with a preponderance of 8 year old clams (Figure 16). At Fury Island, there was a much wider distribution of size and ages, size ranging from 24-93 mm and age from 2-16 years (Figure 17). At Big Frypan Bay shell length ranged from 25-67 mm and age from 2-12 years (Figure 18). Growth, as determined from the sample taken at Fury Island, was moderate; it required about 6.5 years to attain a shell length of 63 mm (Figure 19).

Littleneck Clams

Littleneck clams were abundant in the area and density ranged from 0-180 clams m-2 (Table 3). At Klaquaek Channel, size ranged from 26-50 mm TL and age from 3-7 with a preponderance of 6- and 7-year-olds (Figure 20). As has been found so commonly on beaches in the north coast area, many of the littlenecks were stunted. At Fury Island, size ranged from 30-64 mm TL and age from 3-9 years (Figure 21). At Big Frypan Bay size ranged from 29-46 mm TL and age from 3-8 years; most were 5 and 6 years of age (Figure 22). Growth, as measured from the sample taken at Fury Island was moderate, a TL of 38 mm was attained in about 4 years (Figure 23).

Manila and Varnish Clams

No live Manila clams or dead shell were found on any beaches sampled in 2004, which agrees with findings of previous surveys. No explanation can be given for the absence ofManila clams from Rivers Inlet, since suitable habitat is present. Manila clams occur in Fish Egg Inlet immediately to the north ofRivers Inlet and are common farther north in the Bella Bella area. As seen in the present survey, they are present to the south of Rivers Inlet in Smith Sound. Iflarvae have settled in the area it would appear that a successful resident population has not been established.

No live varnish clams or dead shell were found in Rivers Inlet.

Other Species

Softshells were common at Klaquaek Channel and density ranged from 4-52 clams m-2 (Table 3). Size ranged from 44-74 mm TL and age from 2-7 years (Figure 24). Growth was calculated for the sample; it required about 3.5 years to attain a size of 50 mm TL (Figure 25). 8

Cockles were common at Fury Island and Big Frypan Bay where densities ranged from 17-52 clams m-2 (Table 3). Size at Fury Island was 16-86 mm TL and age 1-8 years (Figure 26). An estimate of growth rate showed a shell height of 50 mm was attained in about 3.5 years (Figure 27).

Fat horse clams were found at Klaquaek Channel and Fury Island where densities ranged from 0-48 clams m-2 (Table 3). Single specimens of truncated softshell were found at Fury Island and Big Frypan Bay. A pair of shells of oblique-lined yoldia were found at Kilbella Bay, obviously washed up on the beach from deeper water.

Virtually no bivalves were found on the two beaches at the head of the Inlet (Table 2) except for a few Baltic macoma, softshells and blue mussels. The habitat was unsuitable for bivalves. The Whannock River estuary was surveyed in 1996 by Aquametrix Research and Axys Environmental Consulting (1997); they reported no evidence of bivalves of any sort.

Other Observations

Two five-minute plankton tows were made in Rivers Inlet (Table 4). A tow taken near the junction of Darby and Klaquaek Channels contained very few bivalve larvae; most were eyed-stage Mytilus, with one hiatella larva observed. A tow taken in Kilbella Bay contained virtually no bivalve larvae, onlyone Mytilus larva was observed. Both tows showed indications of heavy phytoplankton blooms. Surface water temperatures off the beaches at the mouth of the inlet were 12-13°C and temperatures were 13-14°C off the two beaches at the head of the inlet (Table 2).

Burke Channel

Burke Channel extends from its confluence with Fitz Hugh Sound northward between the mainland and King Island for a distance of 61 km where it meets Dean Channel (Figure 28). It is typical of many channels and inlets in the North Coast; narrow, steep sloped with little intertidal area, therefore intertidal clam habitat is minimal.

In previous surveys, extensive sampling was undertaken in the Fitz Hugh Sound area, primarily to determine the presence or absence of Manila clams (Bourne et ai. 1994; Bourne and Heritage 1997; Heritage et ai. 1998). In 2001 survey work was extended to include sampling in Fisher Channel and the head ofDean Channel (Gillespie et ai. 2004). Manila clams were found in Fitz Hugh Sound and the lower part of Fisher Channel but not in the upper part ofDean Channel. Limited surveys in Burke Channel in 1996 (Aquametrix Research and Axys Environmental Consulting 1997) did not reveal the presence of Manila clams, nor did they estimate densities or take biological samples of native clam species. Therefore sampling of this area was included in the present survey 9 to assess intertidal bivalve populations on selected beaches and in particular determine if Manila clams were present in the area.

Four beaches were surveyed: Edmund Point, Fougner Bay and tWQ beaches on King Island. All were in the southern part of the Channel since it was believed that if Manila clams were in Burke Channel they would be in the southern part of the Channel before they would be in the northern part. All four beaches had good intertidal bivalve habitat. King Island 1 was surveyed in 1996 (Aquametrix Research and Axys Environmental Consulting 1997, their beach SC_lOO); they reported only cockle, horse and butter clam shell.

Physical Description of Beaches

Area of the four beaches surveyed in Burke Channel ranged from 2-5 ha, with estimated clam bearing areas from 1.5-4.5 ha (Table 2). Slope of all beaches was low. Substrate varied from mud to sand to sand-mud to sand-shell to sand gravel and gravel with considerable amounts of rock of varying sizes. There were two lagoons at Edmund Point. Green sea urchins and sea cucumbers were common at King Island 2.

Bivalve Populations

There was considerable good bivalve habitat although digging was difficult because of the large amount ofrock and cobble present. Quadrats were dug at all four beaches.

Butter Clams

Live butter clams and dead shell were common on all four beaches. Density of live animals ranged from 0-180 clams m-2 (Table 3). There was a preponderance of large, older clams at Edmund Point (Figure 29) and Fougner Bay (Figure 30). At King Island 2 there was a reasonable number of smaller sized clams indicating good recruitment in recent years (Figure 31). Growth was slow at all four locations, it required about 8 years to attain a shell length of 63 mm (Figure 32 and Figure 33).

Littleneck Clams

As in other areas of the North Coast, littleneck clams were common on all four beaches. Although sampling did not target on this species, densities in the four areas ranged from 0-24 clams m-2 (Table 3). There was a preponderance of larger older clams in Fougner Bay, most were larger than 38 mm shell length (Figure 34). 10

Manila Clams

No live Manila clams were found at the four beaches, but dead shells were collected at Edmund Point, indicating the species had been present on this beach (Table 2). If live Manila clams continue to exist on this beach the population is very sparse. Larvae from another area have obviously settled on this beach in the past but whether a resident breeding population has become established is unknown, but it appears unlikely. Water temperatures in the area may be too low to permit gonad maturation or successful larval development and settlement. Further, there is a strong flow of surface water out of the channel that may prevent larvae penetrating to areas farther north.

Growth was calculated from collected dead shell. Growth was slow; it required about 4.5 years to attain a size of 38 mm TL (Figure 35).

Varnish Clams

No live varnish clams or dead shell were observed in Burke Channel.

Other Species

Fat horse clams were common on all four beaches judging by the amount of dead shell on the surface. At King Island 2, density was 24 clams m-2 (Table 3).

Cockles were common on all four beaches as was evident by the amount of dead shell. Densities of 0-12 clams m-2 were found (Table 3).

Macomas were found at relatively high densities at Edmund Point and Fougner Bay (Table 3). Bent-nose macomas were the only macoma species collected at Edmund Point. Although most collected at Fougner Bay were pointed macomas, single specimens of Baltic and bent-nose macomas were collected as well.

Although no softshells were found in the quadrats that were dug they were common on all four beaches as judged by the amount of dead shell on the beaches.

Other Observations

A five-minute plankton tow completed in Burke Channel off King Island 2 (Table 4) contained very few bivalve larvae. Four Mytilus larvae were observed; two in eyed stage, one in straight hinge and O1~e in umbone stage. There were indications of a heavy phytoplankton bloom, which may have made detection of bivalve larvae difficult. One ostracod was observed. Surface water temperatures were low and ranged from 10-13°C (Table 2). 11

South Bentinck Arm

South Bentinck Arm is located at the northern end of Burke and Dean Channels (Figure 36). It is 40 Ian in length and about 1 Ian in width and lies in a broad valley. There is evidence of extensive logging operations that have occurred there in the past. Three rivers flow into the arm that are glacial in origin and deposit quantities of glacial silt into the surface waters of the arm. The surface waters had a bluish-green colour, typical of glacial deposits.

Three beaches were surveyed (the head of South Bentinck Arm, Bentinck Narrows and Taleomy Narrows; Figure 36).

Physical Description of Beaches

Three extensive beaches were sampled that ranged in size from approximately 10 to >20 ha in area (Table 2). Slope of all three beaches was low. Substrate of all three beaches was packed sand-mud with mud and silt on the surface, Taleomy Narrows had some coarse gravel. Wood debris occurred on some beaches and the beaches had probably been used in past logging operations. Substrate of all three beaches was unsuitable as bivalve habitat.

Bivalve Populations

No evidence ofbutter, littleneck, Manila or varnish clams was found on the three beaches, neither live animals or dead shell. Even evidence of littleneck clams, that are ubiquitous throughout the northern area and occur in virtually all locations, was not found. Unsuitable oceanographic conditions and poor habitat eliminated the possibility of establishing significant commercial bivalve populations.

The small bivalve Macoma balthica occurred in large numbers on the beach at the head ofSouth Bentinck Arm. A quadrat was dug and density was determined to be 2,378 clams m-2 (Table 3). Shell length ranged from 6-17 mm (Figure 37). Distinct lines on the shells of these clams were assumed to be annual rings and an assessment showed the clams ranged in age from 1-4 years, most were 3 year olds (Figure 37). A length frequency distribution by age class showed that age 1 clams ranged from 6-10 mm with a mode a 7 mm, age 2 from 9-14 mm with a mode at 10 mm, age 3 from 10-16 mm with a mode at 13-14 mm, and age 4 from 12-17 mm with a mode at 15-16 mm (Figure 38).

The only other bivalve seen in South Bentinck Arm was blue mussel, which was found at all three beaches (Table 2). 12

Other Observations

A five-minute plankton tow taken in Taleomy Narrows (Table 4) contained no bivalve larvae or phytoplankton. The tow contained only silt particles and debris. Surface water temperatures off the three beaches were low and ranged from 12-14°C. Temperature was only 8°C in the Noeick River that emptied into the arm at Taleomy Narrows.

Dean Channel

Dean Channel runs 85 km north from the Fisher Channel to the estuary of the Kimsquit River. It is typical of many channels and inlets in the North Coast; narrow and steep sloped with few intertidal beaches. There is also a strong flow of surface water southward down the channel that may prevent a northward distribution of bivalve larvae. There is evidence of past logging activity along various parts of the channel.

In 2001, sampling was undertaken in Fisher Channel and at the northern end of Dean Channel, but sampling was not done between these areas (Gillespie et ai. 2004). Manila clams were found in the Fisher Channel area but not at the head of Dean Channel. No bivalves were reported after limited sampling in 1996 in Jenny Inlet and Elcho Harbour (Aquametrix Research and Axys Environmental Consulting 1997). In the present survey, sampling was undertaken approximately in the mid Dean Channel area to assess bivalve populations and determine if Manila clams extended that far up the channel. Two beaches were sampled, one at the head of Elcho Harbour and the other on the east side of Dean Channel across from Elcho Harbour (King Island 3).

Physical Description of Beaches

The two beaches ranged in area from 2-4 ha with 0.5-2 ha of clam bearing area (Table 2). Slopes were low to moderate. Both beaches were very rocky but had some patches of sand-mud substrate interspersed among the rock and boulders; digging was difficult. There was a heavy cover of rockweed over much of the beaches.

Bivalve Populations

Numerous exploratory scratches were made but no quadrats were dug on either beach because of the limited amount of suitable habitat and the lack of bivalves.

Butter clam shell was found at King Island 3, but no littleneck shell was found on either beach (Table 2). No evidence of Manila or varnish clams, live animals or dead shell, was found on either beach. Baltic macomas were common on both beaches. 13

Softshells were moderately abundant at Elcho Harbour; although no quadrats were dug, abundance was estimated to be about 20 clams m-2 when the total estimated area ofscratches was considered. Some dead softshell shell was found at King Island 3. A pooled sample ofsoftshells :Ii-om the beach in Elcho Harbour ranged in size from 22-88 mm and in age from 1-9 years (Figure 40). Measurements ofannuli showed that growth was moderate and a size of50 mm TL was attained in about 4 years (Figure 41).

Other Observations

A five-minute plankton tow taken in Dean Channel (Table 4) contained relatively few mussel larvae, with some in umbone stage, and one softshelliarva. Surface water temperature was 15°C offboth beaches (Table 2).

Roscoe Inlet

Roscoe Inlet lies to the east ofBriggs Inlet and extends northward into the Coldwell Peninsula for about 34 km (Figure 42). It is typical ofmany inlets inthe North Coast, narrow with steep slopes and few intertidal beaches.

Most ofthe area surrounding Roscoe Inlet had been sampled previously: Seaforth-Spiller and Return Channels in 1993 (Bourne et at. 1994); Troup Passage, Spiller and Bullock Channels in 1994 (Heritage et at. 1998); and Fisher Channel and Briggs Inlet in 2002 (Gillespie and Bourne 2005). Surveys undertaken in 1996 by Aquametrix Research and Axys Environmental Consulting (1997) reported Manila clams from several beaches in the inlet, but did not estimate densities or collect biological samples. The goal ofthe present survey was to complete sampling in the area by surveying this inlet.

In the present survey, three beaches in Clatse Bay, Shack Bay and Ripley Bay were sampled (Table 1).

Physical Description ofBeaches

The three beaches ranged in area from about 1-1.5 ha with clam bearing areas of 0.2-0.3 ha (Table 2). Slopes were low to moderate. There was considerable rock on all three beaches with pockets ofsand-mud substrate interspersed in between. There were more extensive sand-mud areas towards the low tide line. Rockweed was abundant, as were blue mussels. 14

Bivalve Populations

Numerous exploratory scratches were made in Clatse and Shack Bays, but quadrat sampling was only undertaken in Ripley Bay (Table 3). All three beaches were rocky and it was difficult to dig quadrats in suitable habitat interspersed between rocks.

Butter and Littleneck Clams

No live butter or littlenecks or dead shell were found on the three beaches. Both species, particularly littlenecks, may have been present in low numbers.

Manila Clams

Live Manila clams and dead shells were found on all three beaches. Quadrats dug in Ripley Bay had densities that ranged from 0-28 clam m-2 (Table 3). Shell length of theses clams ranged from 24-45 mm and age from 3-8 years (Figure 43) indicating limited recruitment in recent years. Growth was measured from live clams collected in Ripley Bay and a sample of dead shell from Clatse Bay3 (Figure 44). Growth of live Manila clams from random scratches in Ripley Bay was slow; it required about 5 years to attain a size of 38 mm TL. Growth measured from the dead shell was also slow; it required about 6 years to attain a size of 38 mm TL. Differences between the samples could be due to location or time (we do not know how long ago the Manilas died in Clatse Bay), but no explanation can be given for the generally slow growth rates of Manila clams in this inlet.

It is doubtful ifManila clam populations in Roscoe Inlet are sufficient to be of interest to the commercial industry.

Other Species

Softshells were common on all three beaches. Softshells from random scratches were collected at beach 2, Shack Bay. Size ranged from 36-85 mm TL and age from 2­ 10 years (Figure 45). At Ripley Bay, densities ranged from 0-56 clams m-2 (Table 3). Size ranged from 37-84 mm TL and age from 2-8 years (Figure 46). Growth was reasonable at both locations; it required about 4 years to attain a size of 50 mm TL (Figure 47).

Live cockles and shell were found on all three beaches. Baltic macomas were found on all three beaches, and were common in Clatse and Shack Bays.

3 Surveys in 1996 reported Manila clams to be abundant in Clatse Bay (Aquametrix Research and Axys Environmental Consulting 1997) at their beach SC_137. We examined the beach at the head ofthe bay, their beach SC_138. Because their report was gray literature and not listed in abstract services we were unaware it existed until after our surveys were completed. We estimated growth ofManila clams in Clatse ~ay from dead shells because live Manila clams were difficult to find on the beach we surveyed. 15

Other Observations

A five minute surface plankton tow at Ripley Bay had large quantities of zooplankton that included ostracods (Table 4). There were few bivalve larvae; most were mussels that ranged from early straight hinge to eyed larvae. There were two littleneck larvae. Water temperatures in the inlet were warm, 16°C off all three beaches.

Port Blackney

The Port Blackney area lies at the confluence of Seaforth Channel and Milbanke Sound at the southern end of Mathieson Channel (Figure 48). It is well protected and lies between Cecilia Island and the Don Peninsula north of Powell Anchorage in Reid Passage.

Similar to Roscoe Inlet, much of the area around Port Blackney had been sampled previously (Bourne and Cawdell 1992; Bourne et ai. 1994; Heritage et ai. 1998). The goal of the present work was to complete sampling in the area. A further stimulus for sampling were reports that commercial harvest of Manila clams had occurredin this area and hence it was of interest to assess the extent of Manila clam populations in the area. Peacock et ai. (1998) reported Manila clams from Boat Inlet and Oliver Cove (their beaches NC_016 and NC_017), but not from Passage Cove (NC_01S), nor did they estimate densities or collect biological information.

Three beaches were sampled at Port Blackney; Boat Inlet, Passage Cove and Oliver Cove (Figure 48). Quadrats were dug at all three beaches (Table 3).

Physical Description of Beaches

The three beaches in Port Blackney ranged in area from about 0.1-1.0 ha, with most of each beach being clam bearing area (Table 2). Slope of all three beaches was low. Substrate was sand-mud to sand gravel. Rocks and boulders were present, particularly at Oliver Cove. At Boat Inlet, much of the substrate was sticky mud that made digging difficult. Substrate at the low tide line was mainly mud with eelgrass.

Bivalve Populations

Populations of all three species of commercial interest were present on all beaches, along with fat horse clams, cockles, softshells and pointed and bent-nose macomas (Table 2). 16

Butter Clams

Butter clams were found on all three beaches and density ranged from 0-48 clams m-2 (Table 3). There was abundant dead shell on all three beaches and undoubtedly extensive populations existed in the lower third of all three beaches. In a sample taken in Oliver Cove, size ranged from 18-84 mm TL and age from 2-13 years indicating reasonable recruitment in recent years (Figure 49). Growth was slow and it required about 8 years to attain a shell length of 63 mm (Figure 50).

Littleneck Clams

Evidence of littleneck clams in the form of dead shell was found on all three be::iches, but live calms were only collected in ~uadrats dug in Boat Inlet and Oliver Cove. Here density ranged from 0-56 clams m- (Table 3). At Boat Inlet shell length ranged from 26-56 mm and age from 3-10 years (Figure 51), and in Oliver Cove shell length was from 13-58 mm and age from 2-11 years (Figure 52). Although many of the clams were stunted, the presence of young clams indicated recruitment in recent years.

Manila Clams

Manila clams were abundant in the area as shown by the amount of dead shell on the beach and the presence of live clams in quadrats. They were found in every quadrat dug on the three beaches and density ranged from 1-276 clams m-2 (Table 3). There was a preponderance of legal size clams; in total 80% were larger than 38 mm TL. At Boat Inlet, shell length ranged from 26-52 mm and age from 3-9 years (Figure 53). In Passage Cove, shell length was 18-46 mm and age 2-6 years (Figure 54), and in Oliver Cove shell length was 30-55 mm and age from 3-8 years (Figure 55). At Boat Inlet a broad range of ages were well represented. At Passage Cove most were 4- and 5-year-olds and at Oliver Cove there was a preponderance of 5- and 6-year-olds. Growth was similar but slow at alLthree beaches, it required 4-4.5 years to attain a shell length of 38 mm (Figure 56 and Figure 57).

Populations ofManila clams in this area are sufficient to support commercial harvest.

Varnish Clams

No live varnish clams or dead shell were found.

Other Species

Softshells were common in the area and shell was found on all three beaches (Table 2). Live animals were found in quadrats dug on all three beaches and density 17 ranged from 0-26 clams m-2 at Passage Cove (Table 3). At Passage Cove, size ranged from 19-90 mm TL and age from 1-9 years, indicating there was recruitment in recent years (Figure 58). Growth was similar to that found in other areas in the North Coast; it required about 4 years to attain a shell length of 50 mm (Figure 59).

Shells of fat horse clams were found in Passage and Oliver Coves (Table 2), and one live animal was dug in a quadrat in Oliver Cove (Table 3). Cockle shell was found on all three beaches and live animals were observed in suitable habitat. One live animal was found in a quadrat dU~ in Oliver Cove (Table 3). Pointed macomas were found at densities of 0-16 clams m- in quadrats dug in Boat Inlet and Oliver Cove (Table 3). Shell of the pointed macoma was found on all three beaches, and shell of bent-nose macoma was found in Boat Inlet (Table 2).

Other Observations

A five minute surface plankton tow in the area (Table 4) had large quantities of phytoplankton, mainly chain forming algae including chain forming diatoms and the dinoflagellate Noctiluca scintillans. There was a lot of zooplankton, including ostracods. Very few bivalve larvae present, although some may have been tangled in the algal mass. Only mussel larvae in various stages were observed. Surface water temperature was 11­ 12°e off the three beaches (Table 2).

Tolmie Channel

Tolmie Channel is typical of channels and inlets in the North Coast. It is a narrow channel that extends about 35 km north from Meyers Passage to the southern end of Graham Reach at the south end of Princess Royal Channel (Figure 60). The foreshore is steeply sloped and falls sharply to considerable depths close to shore. The intertidal area is sparse and there are few estuaries or intertidal beaches.

In previous years considerable sampling was undertaken in the Finlayson and Mathieson Channel areas, primarily to assess the northward dispersal ofManila clams (Bourne and Cawde1l1992; Heritage et at. 1998; Gillespie and Bourne 1998). Results of this work showed that Manila clams occurred in the southern part of Finlayson Channel, throughout Mathieson Channel and in Bolin and Windy Bays in Sheep Passage that extends from the northern part of Mathieson Channel eastward where it joins the north end ofFinlayson Channel. In 2000, the northern end ofPrincess Royal Channel was surveyed but no Manila clams were found, and the conclusion was they had not dispersed that far north (Gillespie et at. 2004). Peacock et at. (1998) did not report Manila clams to be present during beach surveys undertaken at Brown Cove and Flat Point (their beaches NC_127 and NC_120, respectively).

The purpose of the present survey was to assess clam populations in the general area of Tolmie Channel and in particular to determine whether Manila clams were 18 present in this area (i.e., did they occur in the area between Sheep Passage and the northern part of Princess Royal Channel). Sampling was undertaken on two days (Table 1). On June 15,2004, surveys were completed in the southern part of Tolmie Channel (Alexander Inlet, Brown Cove and Tolmie Channell) and on June 16 in the area between Sheep Passage and previous sampling locations in Princess Royal Channel (Tolmie Channel 2 and Flat Point).

Physical Description of Beaches

Three beaches were sampled in the southern part ofTolmie Channel on June 15, 2004. Area of these beaches ranged from 0.5-0.7 ha, and estimated clam bearing area was 0.2-0.5 ha (Table 2). There was considerable rock on all three beaches that made digging difficult. There were sand-shell and gravel patches interspersed among the rock that had considerable populations of clams. The lower portion of the beaches was soft mud with eelgrass. Tolmie Channel 1 was posted with DFO signs warning of health risks due to contamination or PSP so the beach was obviously a popular place for harvesting clams, probably by people from nearby Klemtu.

Two beaches were surveyed in the northern part of Tolmie Channel on June 16, 2004 (Table 1). Intertidal area ranged from 0.3-1.0 ha (Table 2). These beaches were located north of Sheep Passage but south of the area sampled in 2000. There was considerable rock on both beaches. There were patches of firm sand and shell interspersed among the rocks, which supported bivalve populations. The lower part was mainly mud with eelgrass.

Bivalve Populations

Butter Clams

. Butter clams were common on all beaches in suitable habitat and density ran§ed from 12-184 clams m-2 in the southern end of the channel and from 30-164 clams m- in the northern channel (Table 3). At Alexander Inlet, shell length was 59-73 mm and age 7-12 years (Figure 61). At Brown Cove, shell length was similar to that at Alexander Inlet, 59-73 mm but there was a wider spread in ages, 5-16 years (Figure 62). Butter clams were most abundantat Tolmie Channell where shell length was 15-89 mm and age ranged from 1-16 years (Figure 63). Recruitment was good at Tolmie Channell and there were frequency modes at age 6 and 12. At Tolmie Channel 2, shell length ranged from 51-91 mm and age from 8-1~ years (Figure 64). At Flat Point, all of the butter clams were small; length was 17-42 mm and age from 2-6 years (Figure 65).

Growth rates showed growth was slow, it required about 9 years to attain a size of 63 mm TL at all three beaches (Figure 66 and Figure 67). Growth rates were calculated for butter clams found in high and low density areas at Tolmie Channel 2. In the low 19 density area a size of 63 mm TL was attained in about 8 years and in the high density area in about 9 years (Figure 68).

Littleneck Clams

Littleneck clams were common in suitable habitat on all beaches in Tolmie Channel and density ranged from 2-45 clams m-2 in the south and from 8-260 clams m-2 in the north (Table 3). There was considerable shell on the beaches and densities may have been higher if sampling had targeted on this species. At Alexander Inlet, shell length was 32-47 mm and age from 6-12 years (Figure 69), indicating little recruitment in recent years. At Tolmie Channell, shell length was 19-57 mm and age 2-11 years indicating some recruitment in recent years (Figure 70). There was considerable stunting of littlenecks at both locations. At Tolmie Channel 2, alilittlenecks were large, 44-58 mm TL, and 7-12 years in age (Figure 71). At Flat Eoint there was a much wider spread in both shell length and age; shell length was 17-45 mm and age from 2-10 years (Figure 72). Although some stunting was observed, results at Flat Point indicated good recruitment in recent years.

Manila Clams

There was no evidence ofManila clams, either live animals or dead shell, on any of the beaches in the Tolmie Channel area. Manila clams have not dispersed to the lower end ofTolmie Channel from Meyers Passage or Finlayson Channel, nor northward from Sheep Channel into northern Tolmie Channel or Princess Royal Channel.

Varnish Clams

No evidence of live varnish clams or dead shell was found in the Tolmie Channel area.

Other Species

Dead shell of fat horse clams was found on beaches in both northern and southern Tolmie Channel (Table 2) and two live animals were found in a quadrat at Tolmie Channell (Table 3). Cockles were found on all five beaches and were abundant at Tolmie Channel 2 and Flat Point; maximum density at the latter site was 28 clams m-2 (Table 3). Dead softshell valves were found at Alexander Inlet, but were not reported from other locations and no live animals were collected. Baltic, bent-nose and pointed macomas or their shells were observed in various combinations on all beaches (Table 2). Live truncated softshells were collected in Alexander Inlet and at Tolmie Channell and shells were observed at Flat Point: Shells of large fan horsemussels were observed at Tolmie Channell, and live Arctic hiatella were observed at Flat Point.

Dungeness crabs (newly settled juveniles, subadults and adults) were common on the lower reaches of Brown Cove and Tolmie Channell and 2 (Table 2). 20

Other Observations

Five minute surface plankton tows were taken in Tolmie Channel on June 15 and offFlat Point on June 16 (Table 4). Both tows had considerable algae in them; obviously there was a bloom at both locations. Most of the algae were chain forming algae, including chain forming diatoms. Desmids were present in both tows. There was little zooplankton. Very few bivalve larvae were found in either tow; all were mussel larvae in various stages of development. Surface water temperature off all five beaches was lOoC (Table 2).

Spider Anchorage

Spider Anchorage is a protected body of water on the southern side of Hunter Island that is surrounded by an archipelago of small islands (Figure 73). There are small pocket beaches on these islands that have populations of bivalves.

The Spider Anchorage area had been surveyed previously; indeed it was the place where Manila clams were first found north of Vancouver Island (Bourne 1982). The area was extensively resurveyed in 1991 at which time Manila clams were found in several places but not in abundance (Bourne et al. 1994). Focus in the 1991 survey was to assess Manila clam population and little attention was paid to other species. The goal of the present survey was to assess bivalve populations in general and to again assess the extent of the Manila clam populations. We also sought to determine if varnish clams were present in the area since dispersal of this species may be similar to that of Manila clams.

In the present survey sampling was undertaken on five beaches on the shores of Hurricane Island and one beach on Hunter Island (Figure 73).

Physical Description of Beaches

All six beaches surveyed in the Spider Anchorage area were pocket beaches that varied in size and clam bearing area from <0.1 to 0.2 ha (Table 2). Slope of the beaches was low to moderate. On most beaches the substrate was gravel-sand with considerable rock at the high tide line. Substrate on the lower parts of the beaches was mostly mud with eelgrass. Overall the amount of suitable habitat for bivalves was limited.

Bivalve Populations

Although the beaches in the Spider Anchorage area are small they have suitable habitat for bivalves. Six beaches were surveyed and quadrats were dug on three of them, Hurricane Island 1, Hurricane Island 4 and Hunter Island (Table 3). 21

Butter Clams

Evidence of butter clams was found on all six beaches, either as live animals or dead shell; old shell was plentiful on most of the beaches (Table 2). In quadrats dug on Hurricane Island 1, Hurricane Island 4 and Hunter Island, density of butter clams ranged from 3-56 clams m-2 (Table 3). Most were legal size, i.e. 63 mm or larger. At Hurricane Island 1, shell length ranged from 44-82 mm and age from 6-13 years (Figure 74). At Hurricane Island 4, all butter clams were large; size ranged from 66-84 mm TL and age from 8-15 years (Figure 75). An analysis of growth of the pooled sample of butter clams from Spider Anchorage showed that growth was slow; a shell length of 63 mm was attained in about 8 years (Figure 76).

Littleneck Clams

. Evidence of littleneck clams, either live animals or dead shell, was found on most beaches (Table 2). In quadrats dug at Hurricane Island 1 and 4 and Hunter Island, density of littlenecks ranged from 0-15 clams m-2 (Table 3). Higher densities would probably have been found if sampling had targeted on this species. Littlenecks collected at Hunter Island ranged in size from 22-41 mm TL and in age from 3-9 years (Figure 77). As in other areas of the North Coast, many of the littlenecks were stunted.

Manila Clams

Evidence of Manila clams, either live animals or dead shell, was found on all six beaches (Table 2). Much of the dead shell was old and badly eroded indicating it had been there for several years. Of the quadrats dug at Hurricane Island 1 and 4 and Hunter Island, live Manila clams were only found at Hunter Island and density was 20 clams m-2 (Table 3). Most of these Manila clams were large and old; shell length ranged from 36­ 54 mm and age from 3 to 7 years, most were 6 years old (Figure 78). As recorded in the previous survey, growth was slow and it required about 4.5 years to attain a shell length of 38 mm (Figure 79).

The Manila clam population is maintaining itself in Spider Anchorage but an extensive population has not accumulated.

Varnish Clams

No evidence of varnish clams, live animals or dead shell, was found in Spider Anchorage.

Other Species

Evidence of softshells, either live animals or dead shell was found on most beaches. At Hurricane Island 1, a density of 22 clams m-2 was recorded (Table 3). There was a wide range of shell length and ages of these clams, 21-111 mm and 1-13 years 22

(Figure 80). Growth was slightly faster than recorded in other areas, it required about 3.5 years to attain a shell length of 50 mm (Figure 81).

Both live cockles and dead shell was found on most of the beaches (Table 2). Bent-nose macoma were observed at Hurricane Island 4. Shells of fat horse clams were found on four of the beaches and a density of 4 clams m-2 occurred at Hurricane Island 1 (Table 3).

Other Observations

Surface water temperature off the six beaches ranged from II-14°C (Table 2).

Kildidt Sound

Kildidt Sound is a protected area that lies to the east of Spider Anchorage (Figure 82). Watt Bay in particular is well protected and there are several small beaches tucked into coves in the area.

The Kildidt Sound area was surveyed briefly in 1991 when four beaches in the Watt Bay area were visited, but no sampling was undertaken (Bourne et ai. 1994). Evidence ofManila clams was found in the area and a small population of Olympia oysters was observed at one site. Surveys in 1996 (Aquametrix Research and Axys Environmental Consulting 1997) noted Manila clams on three beaches in Kildidt Lagoon, but no beaches in the sound were surveyed.

The aim of the present sampling was to undertake a more thorough investigation of bivalve populations in the area and in particular to determine the extent ofManila clam and native oyster populations. Five beaches were surveyed during the present work; three in Watt Bay, and one beach in each of Goodlad Bay and Stewart Inlet (Table 2).

Physical Description of Beaches

The five beaches surveyed in Kildidt Sound varied in area from <0.1 to 0.3 ha, with estimated clam bearing area from <0.1-0.2 ha (Table 2). Slope of the five beaches was low to moderate. There was considerable rock on most of the beaches and substrate between the rocky areas was sand-gravel to sand-mud to mud at lower beach levels. Eelgrass beds were present at the.lower margin of most beaches.

Bivalve Populations

Although numerous exploratory scratches were made on all five beaches, quadrat sampling was only undertaken at Watt Bay 1 (Table 3). There was a rich bivalve fauna 23 on the beaches as indicated by the presence of live animals and copious amount of dead shell on all five beaches (Table 2).

Butter Clams

Evidence of butter clams, either live animals or dead shell, was found on all five beaches. There were reasonable populations of butter clams at the lower levels of the intertidal area on all five beaches. At Watt Bay 1, density of butter clams ranged from 104-120 clams m-2 (Table 3). Most (86%) were smaller than 63 mm TL. Shell length of the butter clams in both quadrats ranged from 19-69 mm and age from 1-11 years, most were 5-7 years (Figure 83) indicating good recruitment in recent years. Growth was slow and it required about 10 years for butter clams in this area to attain a shell length of 63 mm (Figure 84).

Littleneck Clams

Littleneck clams were common in the area and live animals were found on all five beaches (Table 2). There was also considerable dead shell on the beaches indicating extensive populations in suitable habitat. Density in the two quadrats ranged from 28-72 clams m-2 (Table 3). There were wide distributions of size and age of littlenecks; shell length ranged from 14-56 mm and age from 2-9 years, although most were 6-8 years old (Figure 85).

Manila Clams

Manila clams are generally dispersed in the area and either live animals or dead shell was found on four of the beaches (Table 2). No Manila clams were found in the two quadrats dug at Watt Bay 1 (Table 3), however, they were found in numerous exploratory scratches dug on all five beaches. These were used to provide an analysis of size and age distribution and growth rate. Shell length ranged from 28-58 mm and age from 3-9 years with most being 6 and 7 years old (Figure 86). This shows that some rec!Uitment has occurred in recent years. Growth was slow and it required about 4 years to attain a shell length of 38 mm (Figure 87).

Although Manila clams are present in the area it appears the population is limited but it is maintaining itself with sufficient recruitment. Density is low and the amount of habitat is limited. It is doubtfuUf the populations are sufficient to be of interest to the commercial industry, nor would they be able to withstand sustained fishing pressure.

Varnish Clams

No evidence of varnish clams, live animals or dead shell, was found in Kildidt Sound. 24

Other Species

Softshells were common in the area and live animals and dead shell were found on most beaches (Table 2). Cockles were common on some beaches and density in the quadrats at Watt Bay 1 was 8-12 clams m-2 (Table 3). They were present in areas with softer muddy substrate.

In the 1991 survey, native oysters were found in the Watt Bay area and it was of interest to determine ifthe population still existed. In the present survey dead shell of native oysters was found at Watt Bay 1 and live animals were found in a lagoon at Watt Bay 3. The population appears to be maintaining itself. As has been found in other areas, these oysters occurred in a lagoon. Lagoon areas in the North Coast should be surveyed closely to determine ifnative oysters are present in them.

Other Observations

A five minute surface plankton tow taken offStewart Island (Table 4) had massive amounts ofphytoplankton. Most ofthis was chain forming algae and chain forming diatoms, but Noctiluca scintillans was present. There was a great deal of zooplankton. There were few bivalve larvae; all observed were mussel larvae in various stages ofdevelopment. There was a large amount of eggs, which may have been bivalve eggs. Surface water temperature offthe five beaches was IS-17°C (Table 2).

Broughton Strait

Cluxewe River Estuary

The extensive butter clam beach at the mouth ofthe Cluxewe River was surveyed in 2002 (Gillespie and Bourne 2005). The only species recorded at that time were butter and littleneck clams and cockles. No evidence was found ofManila or varnish clams. We received a reliable report ofa single pair ofvarnish clam shells collected from the beach at Cluxewe late in 2002 (K. Marcus, DFO Nanaimo, pers. comm.).

We surveyed the beach to the southeast ofthe butter clam beach, including the entire Cluxewe estuary and a stretch ofbeach east ofthe estuary (Figure 88). Only butter, littleneck and cockle shell were found, and scratches produced only live butter clams. No evidence ofManila or varnish clams was found. We can only assume that varnish clams, ifthey still exist on this beach, are at densities too low to be easily detected in an exploratory survey. 25

DISCUSSION

As in previous years, results of the present survey have increased our knowledge of the biology and status of bivalve populations in the North and Central Coasts. An extensive body of information has accumulated as a result of these surveys that can provide a solid biological basis for management policies of present fisheries or potential expansion of fisheries for other species.

Butter Clams

Little can be added to what has been said already in previous reports about butter clam resources in the North Coast. Methods used in these surveys were not designed to give an accurate estimate of butter clam populations, but they provide an indication of the extent of populations. There are extensive populations of butter clams in suitable habitat in the lower third of many beaches in the North Coast. Generally there is a wide range of sizes and ages in populations, indicating good recruitment in recent years. Growth has been accurately assessed in many areas and it is slow relative to South Coast populations; it requires 6-10 years to attain the legal size of 63 mm TL.

Prior to the demise of the butter clam fishery in the North Coast in the early 1960's, annual landings of 2,500-3,000 t occurred. Populations of butter clams in the North Coast would probably support similar landings today, however, with present day costs of harvesting and processing it is not economically viable to harvest this resource. Whether the economics of harvesting and processing butter clams will improve in the future remains to be seen.

As has been stated previously, efforts should continue to collect information on butter clam resources throughout B.C. so that if a fishery develops information is available for sound management of the resource.

Littleneck Clams

The situation for littleneck clam resources in the North Coast is similar to that for butter clam resources.

Littleneck clams are probably the most common infaunal bivalve on intertidal beaches in B.C. Sampling during the present and previous surveys has not been designed to accurately assess populations oflittlenecks, but nevertheless large populations have been found on many beaches throughout B.C. There are generally wide distributions of size and age, indicating good recent recruitment. Growth is moderate in the North Coast and the legal size of 38 mm TL is attained in 4-5 years. On many beaches significant portions of the littleneck population are stunted, many clams so badly distorted that they resemble small walnuts. The reason for this stunting is unknown but it may be due to environmental causes, high densities, cold temperatures, or genetic factors. 26

Present annual landings of littlenecks in B.C. total less than 250 t. The problem is that present markets have little interest in littlenecks since they have difficulty selling them. One way industry could assist in increasing the value of the molluscan shellfish resource would be to put some effort into devising methods to market this species so that a fishery is economically viable.

Until extensive markets are found for littlenecks the aim in future surveys should be the same for littlenecks as for butter clams; continue to collect biological data so that if a fishery develops sufficient information exists to manage the resource properly.

Manila Clams

Information continues to be gathered on the dispersal and state of populations of Manila clams in the North Coast. Manila clams were found in many areas during the present survey but extensive populations that could support commercial harvest were only found at Port Blackney. It is understood commercial harvest has occurred in this area. Results of this survey indicate that populations can sustain commercial harvest at current levels.

The small Manila clam population at the mouth of Smith Sound has increased slightly since the previous assessment in 1993 (Bourne et al. 1997). As well, other small populations were reported further into Smith and Boswell Inlets (Aquametrix Research and Axys Environmental Consulting 1997). It is evident this population has become established and is maintaining itself, however it is much too small to support commercial harvest.

The low incidence and abundance of Manila clams in Rivers Inlet cannot be explained. They were not found there in an extensive survey in 1991 (Bourne et al. 1994) and the only evidence of the species in Rivers Inlet is dead shell of one clam found in Goose Bay in 1993 (Bourne and Heritage 1997) and qualitative reports of their presence from three beaches in inner Klaquaek Channel in 1996 (Aquametrix Research and Axys Environmental Consulting 1997). Cursory surveys in 1996 did not report Manila clams from three beaches in Goose Bay (Aquametrix Research and Axys Environmental Consulting 1997), so this population may have disappeared. Suitable habitat exists in the islands at the mouth of the inlet and populations of Manila clams exist both north and south of the area. Iflarvae have settled in this area they have not survived to establish extensive or abundant populations. Further exploration of beaches in Klaquaek Channel is required t9 provide data on abundance and biological characteristics of Manila populations reported from the area.

Dead shell of Manila clams was found in the lower part of Burke Channel but no live animals. These dead animals probably resulted from recruitment of larvae from one or two spawning events elsewhere that settled on the beach and survived. It would 27 appear that a breeding population was not established and no further recruitment of larvae from elsewhere occurred.

The lack of Manila clams in the mid to upper areas of Burke and Dean Channels and in South Bentinck Arm is probably due to several factors. Suitable habitat is limited. The surface waters are cold and probably contain quantities of glacial melt waters that prevent temperatures increasing to levels where larvae and juveniles could survive. Further, there is a strong flow of surface water down these channels that could prevent larvae from being carried farther north.

The presence of Manila clams in Roscoe Inlet was not unexpected since they are present in surrounding areas (Bourne and Cawde1l1992; Bourne et al. 1994; Heritage et al. 1998). What was surprising was the populations were limited to edge habitats on large beaches and small pockets of habitat along the inlet shores, and that they were not _more extensive.

Similarly the population at Port Blackney was expected since it too is surrounded by areas supporting Manila clam populations. The surprise was the extent of the population, the largest found during the survey.

Sampling in the Tolmie Channel-Graham Reach area established the northern limit ofManila clam dispersal in this area is the northern end of Mathieson Channel and western end of Sheep Passage as found in the 1998 survey (Gillespie and Bourne 2000). Further dispersal northward via Graham Reach and Princess Louise Channel is probably prevented by cold water temperatures that do not permit survival of larvae orjuveniles.

Sampling in the Spider Anchorage-Kildidt Sound area showed that although Manila clams continue in this area the populations are not extensive and have not increased since the previous survey in 1991 (Bourne et al. 1994). The populations are able to maintain themselves but little more. Furhter investigation of Kildidt Lagoon and other entrained inlets in the area is required to quantitatively assess abundance and biological characteristics of populations there.

In general there was a preponderance of larger, older Manila clams in areas where they were found indicating limited recruitment in recent years. However, where Manila clams were found, the populations appear to be well established and able to maintain themselves.

Surface water temperatures were generally cool; generally well below 15°C, the temperature needed for gonadal d~velopment and spawning in Manila clams. Only in Roscoe Inlet was a surface water temperature over 15°C recorded. Water temperatures may increase slightly in some areas in July-August but they probably remain too cold in areas like Burke, Dean and Tolmie Channels to permit successful breeding of Manila clams. 28

Growth ofManila clams was generally slow and it required 3.5-5 years to attain a shell length of38 mm, the minimum size limit in the commercial fishery.

Varnish Clams

Results ofthese surveys indicated that the current northern limit ofvarnish clams in B.C. is fudian Island in Smith Sound. The shells collected there are significant as they are the first found north ofVancouver Island, and provide evidence that this exotic species is spreading into the North Coast. The nearest records to this are shells taken at Stories Beach, Fort Rupert in Queen Charlotte Strait4 and live animals collected at three locations in Checlest Bay on the west coast ofVancouver Island (Gillespie and Bourne 2005).

. Although shells ofone animal were found at the Cluxewe River and fudian Island, no live animals were found. This suggests that we are seeing settlement ofa few individual larvae that drifted from spawning populations elsewhere, but no establishment ofpopulations. Further monitoring ofbeaches in Queen Charlotte and Johnstone Straits is required to document whether these records represent ephemeral individuals remaining from failed populations, or the first pioneers that will establish populations in the near future.

It is interesting to note that the dispersal route for the species to the North Coast, should they become established there, is different from that hypothesized for Manila clams. Bourne (1982) postulated that North Coast populations ofManila clams were the result oflarval drift from spawning populations in Quatsino Sound. He argued that distribution patterns supported an outside dispersal route with limited colonization of Queen Charlotte and Johnstone Straits from Quatsino Sound, and presented oceanographic data that support his hypotheses ofcold-water barriers to larval survival and current patterns that would explain the resulting distribution ofpopulations. Gillespie and Bourne (2005) did not find varnish clams during a 2002 survey in Winter Harbour, although they located several populations south ofBrooks Peninsula. The presence ofvamish clams on beaches in Queen Charlotte and Johnstone Straits, their appearance in Smith Sound and there apparent absence from Spider Anchorage and Kildidt Sound all support the provisional hypothesis that they are dispersing through inside waters. Further investigation ofbeaches to confirm their absence from Quatsino Sound and monitor population trends in inside waters could provide information to confirm or refute this hypothesis.

Olympia Oysters

Olympia oysters have been found in a few isolated areas in the North Coast, including Kildidt Sound (Bourne et al. 1994, this report) and Fish Egg fulet (Bourne and

4 The shells from Stories Beach were accompanied by anecdotal information that live varnish clams accorred there as well (A. Stewart, Port Hardy, pers. comm.). 29

Heritage 1997; Gillespie et ai. 2004). We have also received reliable reports of a small population in the northern end of Gale Passage (T. Johannson, DFO Central Coast Area, Port Hardy); this is the northernmost population for which we have solid documentation.

Olympia oysters are often found in lagoons, as in Kildidt Sound, where being continually immersed in water even at low tide mitigates cold winter temperatures. Because Olympia oysters are often found in lagoons, these areas should be carefully examined in future surveys. The species has no commercial value but information on its occurrence and abundance should be collected, as they were listed as a Species of Concern by the Committee on the Status ofEndangered Wildlife in Canada (COSEWIC) in November of 2000 (COSEWIC 2004).

Other Species

This survey, like those in previous years, focused mainly on collecting data on butter, littleneck and Manila clam resources. However, information on other species is accumulating and results of this survey will contribute to this knowledge.

Horse clams, mainly T. capax, are a common bivalve in the lower third of many intertidal beaches in northern B.C. Results of our survey work do little more than establish the presence or absence of the species. Although there is probably an extensive horse clam resource in the North Coast, as there is in the South Coast, a fishery has not been developed (Lauzier et ai. 1998).

Cockles are present on many beaches in the North Coast, particularly in the lower half of beaches in soft substrate. Results of the present and past surveys report the presence or absence of the species and give some estimate of the extent of populations, as well as determining growth rates. The species has no commercial value in B.C. and even if dense extensive populations existed, it is doubtful if industry would have any interest in harvesting them. However, they do have particular significance to First Nations as a food species, especially in the North Coast (Baxter et ai., in press).

Softshells are another abundant bivalve on many beaches in the North Coast. The species is highly prized on the Atlantic coast of Canada and supports a valuable fishery there, but it has never been accepted in B.C. although it is used to a limited extent in the recreational fishery. A small commercial harvest occurred in the past in the state of Washington but has never existed in B.C. It is doubtful ifpopulations of softshells could support a targeted commercial fishery in B.C. even if suitable economic conditions prevailed, but it could be harvested along with other species. Growth has been assessed in many areas and it generally takes about 4 years to attain a shell length of 50 mm.

Information on Baltic, pointed and bent-nose macomas was collected. The occurrence of a dense population of Baltic macomas in south Bentnick Arm and the calculation of a growth rate for this population is of note. 30

Plankton Tows

Numbers ofbivalve larvae were only found in the tow in Smith Inlet. Most larvae observed were mussel larvae in various developmental stages. The lack oflarvae in other areas is due in part to tows being made in June. Extensive spawning ofmany bivalves may not have occurred by that time. Another reason for the lack oflarvae was that heavy phytoplankton blooms were occurring in most areas that plugged the plankton net. Larvae may have been caught up in the phytoplankton mass and could not be sorted out for observation. The presence ofthe dinoflagellate Noctiluca scintillans is some tows was ofinterest.

ACKNOWLEDGEMENTS

We thank Capt. Glen Ormiston and the crew ofCCGS VECTOR for their support and assistance during the surveys. Jim Boutillier, Ken Fong and Antan Phillips assisted on the surveys. We thank Jason Dunham and Joanne Lessard for their reviews ofthis manuscript.

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Gillespie, G.B., and Kronlund, A.R. 1999. A manual for intertidal clam surveys. Can. Manuscr. Rep. Fish. Aquat. Sci. 2270: 144 p.

Gillespie, G.B., Norgard, T.C., and Scurrah, F.B. 1999a. Review ofthe Area 7 Manila clam fishery. CSAS Res. Doc. 99/197: 66 p.

Gillespie, G.B., Norgard, T.C., and Scurrah, F.B. 2001a. Status ofManila clam (Venerupis philippinarum) stocks in Area 7, with a proposal for active management ofa data-limited fishery. CSAS Res. Doc. 2001/089: 59 p.

Gillespie, G.E., Parker, M., and Merilees, W. 1999b. Distribution, abundance, biology and fisheries potential ofthe exotic varnish clam (Nuttallia obscurata) in British Columbia. CSAS Res. Doc. 99/193: 39 p.

Gillespie, G.E., Rusch, B., Gormican, S.l, Marshall, R., and Munroe, D. 2001b. Further investigations ofthe fisheries potential ofthe exotic varnish clam (Nuttallia obscurata) in British Columbia. CSAS Res. Doc. 2001/143: 59 p.

Harbo, R.M. 1999. Whelks to whales. Coastal marine life ofthe Pacific Northwest. Harbour Publishing, Madiera Park. 245 p. 32

Harbo, R., Marcus, K., and Boxwell, T. [eds.]. 1997. Intertidal clam resources (Manila, littleneck and butter clams). Vol. 3: The northern inside waters ofVancouver Island and the British Columbia mainland. Can. Manuscr. Rep. Fish. Aquat. Sci. 2418: 79 p.

Heritage, G.D., Gillespie, G.B., and Bourne, N.F. 1998. Exploratory intertidal clam surveys in British Columbia-1994 and 1996. Can. Manuscr. Rep. Fish. Aquat. Sci. 2464: 114 p.

Lambert, P. 1997. Sea cucumbers ofBritish Columbia, Southeast Alaska and Puget Sound. Roy. B.C. Mus. Handbook. UBC Press, Vancouver. 166 p.

Lambert, P. 2000. Sea stars ofBritish Columbia, Southeast Alaska and Puget Sound. Roy. B.C. Mus. Handbook. UBC Press, Vancouver. 186 p.

Lauzier, R.B., Hand, C.M., Campbell, A, and Heizer, S. 1998. A review ofthe biology and fisheries ofhorse clams (Tresus capax and T. nuttallii). CSAS Res. Doc. 89/88. xx p.

Peacock, A.M., Blyth, C.A, Home, C.A, Williams, F.A., Cross, S.F., and Gormican, S.J. 1998. Shellfish culture capability appraisal for the northern Central Coast region. Report prepared for B.C. Ministry ofFisheries, Victoria.

Quayle, D.B. 1966. Paralytic shellfish poisoning - sa fe shellfish. Fisheries Research Board ofCanada Circular 75. 6 p. + figs.

Quayle, D.B., and Bourne, N. 1972. The clam fisheries ofBritish Columbia. Fish. Res. Board Can. Bull. 179: 70 p.

Turgeon, D.D., Quinn, Jr., J.F., Bogan, A.B., Coan, E.V., Hochberg, F.G., Lyons, W.G., Mikkelsen, P.M., Neves, R.I., Roper, C.F.E., Rosenberg, G., Roth, B., Scheltema, A., Thompson, F.G., Vecchione, M., and Williams, J.D. 1998. Common and scientific names ofaquatic invertebrates from the United States and Canada: Mollusks. 2nd Ed. Amer. Fish. Soc. Spec. Pub!. 26: 526 p. 33

Table 1. Location of beaches sampled during exploratory intertidal bivalve surveys in British Columbia, June 2004.

Location Number of Beaches Date

Smith Sound 4 June 3, 2004 Rivers Inlet 7 June 4-5, 2004 Burke Channel 4 June 6,2004 South Bentinck Arm 3 June 7, 2004 Dean Channel 2 June 8, 2004 Roscoe Inlet 3 June 9, 2004 Port Blackney 3 June 14, 2004 Tolmie Channel 5 June 15-16,2004 Spider Anchorage 6 June 17,2004 Kildidt Sound 5 June 18,2004 Broughton Strait 1 June 19, 2004 34

Table 2. Physical description of beaches visited during exploratory intertidal bivalve surveys in British Columbia, 2004. Area is estimated intertidal area, followed by estimated area of good clam habitat in brackets.

Beach Area Slope Substrate Remarks No. (ha)

,Smith Sound

1 3.0 Low, Sand/mud on Indian Island (51 °17.0TN, (2.0) increasing lower beach, 127°38.66'W). Sparse eelgrass over near high sand/shell on most of lower beach, density tide line upper beach, increasing at low tide line. Rocks at gravel and high tide line covered in acorn cobbles at high barnacles, blue mussels and rockweed. tide line. Lots of rubbish on beach; old truck frame, glass and china fragments, shoes. Shell of Manila, littleneck and butter abundant, horse, cockle, pointed and bent-nose macoma shell also present. One varnish clam shell collected. Water temperature 14°e. 2 0.5 Low. Packed Fly Basin (51°16.4TN, 127°36.88'W). «0.1) sand/mud with Eelgrass and Laminaria at low density rock at high tide over lower beach, acorn barnacles, line. blue mussels and rockweed on rocks in upper intertidal. Not much clam shell on beach, small fringe of gravel near high tide mark. Not much shell; Manila, littleneck, butter, horse, softshell and bent-nose macoma present. No varnish clams or shell. Water temperature 13°e. 35

Table 2. cont'd.

Beach Area Slope Substrate Remarks No. (ha)

Smith Sound (cont'd)

3 1.0 Low over Lower beach Broad Bay (51 °17.05'N, (0.5) most of was shell/sand 127°35.70'W). Lower beach densely beach, with one large covered in eelgrass, moonsnails and increasing tide pool; upper moonsnail egg collars abundant. Mid­ near high beach saddle was beach area between soft and hard tide line. a rocky channel substrates covered with thick layer of with several clam shell (butter, littleneck, cockle large and and Manila). Upper rocky area numerous small supported large populations of giant tide pools. green and aggregating green anemones, sea stars, chitons and snails. Shell of pointed macoma and horsemussel also present. No varnish clams or shell. Water temperature 13°C. 4 2.0 Low. Packed North side of Greaves Island «0.1) sand/mud/clay, (51°18.16'N, 127°34.48'W). Lower some gravel in beach sparsely covered with eelgrass, fringe near high some higher density patches near low tide line, upper tide line, moonsnails and egg collars margin rock. present at low abundance. Rocky margin supports acorn barnacles, blue mussels and rockweed. Poor clam habitat, not much shell. Littleneck shell appears stunted. Shell of Manila, littleneck, butter, horse (both species) cockle, softshell, pointed, bent-nose and white-sand macomas. No varnish clams or shell. Water temperature 13°C. 36

Table 2. cont'd.

Beach Area Slope Substrate Remarks No. (ha)

Rivers Inlet

1 0.5 Moderate. Shell/sand with Head of Klaquaek Channel (0.3) rock at high tide (51°30.28'N,127°41.18'W). Middle line. to upper beach covered in blue mussel, thatched barnacle and rockweed. Eelgrass increasing in density at low tide line. Butter and littleneck clams very abundant, cockles and horse clams moderately abundant. Softshells abundant at high tide levels in soft substrate. Shell of butter, littleneck, horse, cockle, pointed and Baltic macoma also present. No Manila or varnish clams or shell. Water temperature 13°C. 2 0.1 Low to Hard packed Penrose Island North (51°30.49'N, «0.1) moderate. shell/sand in 127°42.19'W). Rocks covered in center ofbeach, thatched barnacle, blue mussel, boulders and rockweed and tarspot cucumbers. bedrock on Butter littleneck and horse shell middle to upper abundant, cockle and softshell shell beach levels. also present. Water temperature 13°C. 3 4.0 Low to Shell/sand over Fury Island (51°29.17'N, (3.0) moderate. most of beach, 127°45.64'W). Rocks on upper beach with some mud and any vertical structure (e.g., large in depressions stump) covered in blue mussels, acorn and at the low and thatched barnacles and rockweed. tide line. Sea lettuce in patches on lower beach, Bedrock and eelgrass primarily below low tide line. large boulders Live butter, littleneck, cockle and near high tide horse clams, shell of horsemussel, line. One large California mussel and softshells tidepool high on present. Live Pacific oysters and shell be?ch and large on longline found on beach. No lagoon in small Manila or varnish clams or shell embayment on found. Water temperature 14°C. west side of beach. 37

Table 2. cont'd.

Beach Area Slope Substrate Remarks No. (ha)

Rivers Inlet (cont'd)

4 0.1 Moderate Shell/sand with Big Frypan Bay (51 °29.05'N, (0.1) sloped increasing mud 127°42.38'W). Rocky upper intertidal hummock under eelgrass. covered in blue mussels, thatched with small Bedrock near barnacles and rockweed. Eelgrass low slope high tide line. density increased near low tide line. area on Live littleneck, butter, horse cockle top. and softshell present, shell of all abundant. No Manila or varnish clams or shell found. Water temperature 15°C. 5 0.1 Low. Shell/sand, Taylor Bay (51 °30.42'N, (0.1) bedrock and rock 127°35.46'W). Very late on rising at high tide line. tide, 90uld not fully assess beach. Sand blue in Upper beach covered with blue color, indicating mussel, thatched barnacle and most of crushed rockweed. Some littleneck and butter shell was mussel. shell high on beach. Water temperature Boe. 6 >20.0 Low. Packed sand Kilbella Bay (51°41.69'N, with wood 127°21.34'W). Beach barren; no good debris, areas of clam habitat. Mysids, juvenile H2S, rocky salmonids, flatfish and sculpins below margin with low tide line. Sparsely scattered shell, acorn barnacles commonly Baltic macoma, softshell and stunted less common, one blue mussel shell rockweed. seen. Water temperature 11 °e. 7 3.0 Low. Lower beach Whannock River estuary (51 °40.17'N, packed sand, 127°15.99'W). Beach largely barren; upper beach sand no good clam habitat. Baltic macoma with rocks, shell sparsely scattered, one softshell heavily scoured. shell found. Three bent-nose macoma Wood debris shells found on beach furthest from un~er sand, H2S river mouth. Shoals of mysids and bubbling in some juvenile salmonids below low places. Rock tide line. Northwestern crows digging with acorn sandlance from sand near river mouth. barnacles and Water temperature 10°C. rockweed. 38

Table 2. cont'd.

Beach Area Slope Substrate Remarks No. (ha)

Burke Channel

1 2.0 Low. Sand/gravel in Edmund Point (51 °54.06'N, (2.0) upper beach 127°52.1O'W). Dungeness and red lagoon, rock crabs common in lagoon, lots of sand/shell on moults. Upper lagoon supported small lower beach. butter clams and bent-nose macomas, Rocky area at lower beach had large butter, littleneck mid-beach and horse clams and cockles. separates lagoon Softshells present but rare. Manila and lower beach. shell collected from rocky areas at Margins bedrock mid-beach and head of lagoon. Shell with rockweed, of softshell and Baltic macoma blue mussels and present. Water temperature 13°C, acorn barnacles; both in lagoon and at low tide line. thatched barnacles on rocky break at mid-beach. 2 2.0 Low. Sand/mud with Fougner Bay (51 °54.32'N, (1.5) embedded rock; 127°50.78'W). Beach divided into sand/shell near three areas by rocky outcrops. low tide line. Easternmost area protected by log Rocks with boom. Butter shell common; horse, rockweed, acorn littleneck and cockle shell less barnacles and abundant. Pointed, Baltic and bent- blue mussels at nose macoma shell present. Water high tide line. temperature 13°C. 3 5.0 Low. Firm sand with King Island 1 (51°57.38'N, (4.5) some shelL 127°49.00'W). Broad estuary with a Margins rocky single stream channel meandering with rockweed, across. Dogwinkles common, both acorn barnacles frilled and striped. Butter, littleneck and blue and cockles present at low densities. mu;ssels. Shell of butter, littleneck, and cockle moderately abundant; horse, softshell, bent-nose shell present. Water temperature 12°C. 39

Table 2. cont'd.

Beach Area Slope Substrate Remarks No. (ha)

Burke Channel (cont'd)

4 3.5 Low. Gravel/sand with King Island 2 (51°57.99'N, (2.0) 3 cm layer of 127°45.06'W). Broad semi-circular coarse gravel beach with several small stream and small rock channels. Green urchins, sea on surface. cucumbers and amphipods abundant in Patches of beach top gravel, butter and littleneck clams covered with abundant shallow in substrate. Shell thatched of butter, littleneck and horse barnacle and common; softshell shell present. blue mussel. Water temperature 10°C. 40

Table 2. cont'd.

Beach Area Slope Substrate Remarks No. (ha)

South Bentinck Arm

1 >10.0 Low. Packed Head of South Bentinck Arm (min.) sand/mud with (51°57.90'N, 126°40.90'W). Broad silt on surface. beach across head of inlet. Pockets of Some soft areas Baltic macomas in firmer substrate, that were patches of blue mussel on solid primarily substrates. Rockweed fairly stunted, silt/mud. very light set of small acorn barnacles. Several stream Water temperature 12°C. channels crossing beach. Upper margin grasses and brush, lateral margins rock with rockweed and blue mussels. 2 >20.0 Low. Packed sand Bentinck Narrows (51°58.89'N, (min.) with mud and silt 126°41.27'W). Extensive but on surface. relatively narrow beach running Wood debris on around margin of narrows. Baltic surface. Upper macomas sparsely distributed in firmer beach rocky with substrate. Patches ofblue mussels on rockweed and solid substrate. Stunted rockweed, blue mussels. acorn barnacles uncommon. Water temperature 14°C. 41

Table 2. cont'd.

Beach Area Slope Substrate Remarks No. (ha)

South Bentinck Arm (cont'd)

3 >20.0 Low. Sand with Taleomy Narrows (52°02.52'N, (min.) scattered patches 126°40.99'W). Extensive beach of gravel and running around margin of narrows and some large logs well up Noeick River. Taleomy River and stumps. crosses beach in several branches. Upper beach Baltic macomas present at moderate grasses and densities in sand. Light set of tiny brush. acorn barnacles; rockweed stunted. Patches of grass and other vegetation on hummocks. Blue mussels relatively scarce, primarily present on and around large logs and stumps that may have drifted onto the beach from elsewhere. Water temperature 14°C on beach, goC in Noeick River. 42

Table 2. cont'd.

Beach Area Slope Substrate Remarks No. (ha)

Dean Channel

1 4.0 Low. Sand/mud with Elcho Harbour (52°23.65'N, (2.0) embedded rock. 127°32.1O'W). Moderately large Mid- to upper beach across head of harbour with one beach very rocky stream channel. Some Baltic macoma with heavy sparsely distributed amongst rocks, rockweed cover, very sparse in sandy areas. Softshells abundant blue in low to moderate density, 2 mussels and approximately 20 m- , in sandy area dense set of adjacent to stream channel. Water acorn barnacles. temperature 15°C. Lower beach sand and mud. 2 2.0 Low to Large rock and King Island 3 (52°19.94'N, (0.5) moderate. boulders 127°27.33'W). Moderately large embedded in beach with large stream channel on sand. Some western end. Very rocky beach with small areas of small areas of good sand substrate. sand, usually Baltic macoma sparsely distributed covered in blue between rocks and in sandy areas. mussels and Two old butter shells and one softshell acorn barnacles. shell found on western end. Water Thick covering temperature 15°C. of rockweed on upper half of beach. Upper margin grasses and brush. 43

Table 2. cont'd.

Beach Area Slope Substrate Remarks No. (ha)

Roscoe Inlet

1 1.0 Low. Rocky with Clatse Bay (52°20.36'N, (0.2) sand/mud in 127°50.51'W). Very rocky beach with interstices. little clam habitat. Some softshells Rocks covered and cockles in patches of soft substrate with thick low on beach. Old dead Manila shell rockweed, acorn common, softshell and Baltic macoma barnacles and present. No littleneck or butter clam moderate shell. Water temperature 16°C. densities ofblue mussels. 2 1.5 Low. Sand with Shack Bay (52°23.13'N, (0.3) patches of gravel 127°51.43'W). Broad beach exposed and rock. to weather from southeast. Softshell Highly scoured, shells abundant, live clams in patches few acorn of soft substrate at densities of 2 barnacles or approximately 10-20 m- • Manila, mussels, very Baltic macoma and cockle shell little vegetation. present. No littleneck or butter shells. Water temperature 16°C. 3 1.0 Low to Gravel/sand at Ripley Bay (52°25.45'N, (0.2) moderate. mid-beach, 127°53.27'W). Beach divided by large progressively stream channel in center. Live Manila, rocky towards softshell, cockles and Baltic macomas high tide line and on beach at low densities, shell of all increasing sand common. No butter or littleneck shell. towards low tide Water temperature 16°C. line. Rockweed and acorn barnacles increasing towards high tide line, relatively few mussels. 44

Table 2. cont'd.

Beach Area Slope Substrate Remarks No. (ha)

Port Blackney

1 0.4 Low. Sand/mud with Boat Inlet (52°18.42'N, (0.3) rock covered by 128°22.41 'W). A small beach at the acorn barnacles head of the inlet. Substrate was sticky and rockweed at mud with lots of rock; not easily dug. high tide line. Live Manila, littleneck, butter, Eelgrass at low softshell and pointed macomas tide line. One collected. Shell of cockle and bent- stream channel nose macoma were also observed. crossing beach. Water temperature 12°C. 2 0.1 Low. Sand/gravel with Passage Cove (52°18.47'N, (0.1) some mud near 128°21.42'W). A small beach at the low tide line, head of the cove. Live Manila and well drained near softshell collected, shell of butter, high tide line. horse, littleneck, cockle and pointed Bedrock at upper macoma on beach. Water temperature margin, eelgrass 11°C. at low tide line. Small stream channel crossing beach. 3 1.0 Low. Gravel/sand with Oliver Cove (52°18.84'N, (1.0) increased mud 128°21.01'W). A moderately large and eelgrass at beach at the head of the cove. Live low tide line. Manila, littleneck, butter, horse (T. High tide margin capax), softshell, cockle and pointed bedrock and macoma collected, shell of all boulders. abundant on beach. Water temperature 11°C. 45

Table 2. cont'd.

Beach Area Slope Substrate Remarks No. (ha)

Tolmie Channel

1 0.7 Low. Sand/gravel with Alexander Inlet (52°39.52'N, (0.5) embedded rock. 128°37.53'W). A moderately large Bedrock and beach on the northwest shore of the rocks with inlet, above the narrows. Live butter, thatched and littleneck, pointed macomas and acorn barnacles, truncated softshells collected; shell of rockweed and softshell, cockle and Baltic macoma some blue present. Shell of horse clam (T. mussels at high capax) present, some very large. tide line. Difficult digging due to rocks Increased mud embedded in substrate. Water and eelgrass at temperature was lOoC. low tide line. 2 0.5 Low. Sand with Brown Cove (52°41.14'N, (0.2) embedded rock. 128°34.71'W). A moderately large Heavy set of beach at the head of the bay. Live thatched and butter, littleneck and cockle collected, acorn barnacles shell of Baltic and pointed macomas on mid- to upper present. Single quadrat and additional beach; rockweed butter clams for growth analyses dug and blue mussels low in beach in soft substrate. on upper beach. Dungeness crabs abundant subtidally Some patches of in eelgrass. Water temperature was sand and lOoC. barnacle thatch on lower beach, eelgrass below low tide line. One very large stream channel crosses beach. 46

Table 2. cont'd.

Beach Area Slope Substrate Remarks No. (ha)

Tolmie Channel (cont'd)

3 0.5 Low. Sand/shell/gravel Tolmie Channell (S2°41.49'N, (0.5) with some rock 128°32.44'W). A moderately large embedded. beach behind an unnamed island. Live Rocks and butter, littleneck, horse (T. capax), bedrock at high cockle and truncated softshells tide line with collected; shell of fan horsemussel on thatched and beach. Large sunflower stars and acorn barnacles, Dungeness crabs in eel grass below rockweed and low tide line, newly settled Dungeness blue mussels; crabs and small green urchins in gravel eelgrass at low on beach. One large gumboot chiton tide line. found. Water temperature was IDoC. 4 1.0 Low. Firm sand/shell, Tolmie Channel 2 (S2°S1.46'N, (0.9) upper beach rock 128°31.2S'W). A moderately large with rockweed, beach protected by a small island. sparse acorn Live butter, littleneck, cockle, pointed barnacles and andbent-nose macoma collected; shell blue mussels. of butter, littleneck, horse (T. capax) Lower third of and cockle abundant, shell of pointed beach with and bent-nose macoma also present. sparse eelgrass, Adult Dungeness crab abundant low tide line had subtidally. Water temperature was dense mats of 10°C. algae. 5 0.3 Low. Rocky beach Flat Point (S2°S8.70'N, (min.) with small sandy 128°30.80'W). A small beach open to areas. Thick the channel. Live butter, littleneck, covering of cockle and pointed macoma collected; rockweed with shell of butter, littleneck, horse (T. sparse acorn capax) and cockle abundant, shell of barnacles and arctic hiatella, truncated softshells and blue mussels on Baltic macoma also present. Fringed upper third of dogwinkles extremely abundant, dire beach. Thatched whelks also common. Chitons barnacles common, particularly black katy. common on Arctic hiatella abundant under rocks, lower beach. as were small grey sea cucumbers. Water temperature was IDoC. 47

Table 2. cont'd.

Beach Area Slope Substrate Remarks No. (ha)

Spider Anchorage

1 0.1 Moderate. Gravel/sand. Hurricane Island 1 (51°50.52'N, (0.1) High tide line 128°12.29'W). Live littleneck, butter rocks and and softshell collected; Shell of horse bedrock with (T. capax), cockle and red turban heavy cover of present. A few Manila shells present, acorn barnacles all very old and eroded. Blue mud and stunted shrimp, moonsnails and sunflower rockweed. Sand stars observed. Moon jellyfish and sea and eelgrass at blubber common in channel; clinging low tide line. jellyfish observed in eelgrass bed. Water temperature was 12°C. 2 <0.1 Low. Gravel with Hurricane Island 2 (51 °50.53'N, «0.1) heavy algal 128°12.46'W). Live softshells cover on mid- observed; shell of butter common, and lower beach. shell of littleneck, cockle and softshell Boulders at high observed. Very old, eroded Manila tide line covered shell present but not common. Water with acorn temperature was 12°C. barnacles and stunted rockweed; eelgrass in sandy substrate at low tide line. 3 0.1 Low. Gravel with Hurricane Island 3 (51°50.56'N, (0.1) increased sand at 128°12.70'W). No live clams low tide line. observed; shell of butter and softshell Boulders on observed. Few very old, eroded upper beach Manila shells observed. Water covered with temperature was 13°C. acorn barnacles and stunted ro,?kweed; eelgrass at low tide line. 48

Table 2. cont'd.

Beach Area Slope Substrate Remarks No. (ha)

Spider Anchorage (cont'd)

4 0.2 Low. Sand/gravel, Hurricane Island 4 (51°50.86'N, (0.2) boulders at high 128°12.80'W). Live butter, littleneck, tide line with pointed and bent-nose macomas sparse cover of collected; shell of softshell, cockle and acorn barnacles, horse (T. capax) present. Old, eroded stunted Manila shell common; three live rockweed. Manilas collected. Very large Extensive moonsnails common below low tide eelgrass bed line. Water temperature was 11°C. from low tide line subtidally. 5 <0.1 Low. Gravel/sand, Hurricane Island 5 (51°51.08'N, «0.1) boulders at high 128°12.91'W). Live butter, littleneck tide line covered and softshell observed; shell of these in acorn and Manila common, shell of cockle, barnacles and horse (T. capax), California stunted sunsetclam, pointed and Baltic rockweed. macomas present. No live Manilas Eelgrass at low found. Water temperature was 12°C. tide line and subtidally. 6 0.1 Low. Gravel/sand with Hunter Island (51°51.65'N, (0.1) thick cover of 128°11.99'W). Live butter, littleneck, algae on mid- softshell, cockle and Manila collected. and lower beach. Shell of horse (T. capax), pointed and Rocks and Balthic macomas present. Manilas boulders on mid- present only in substrate between to upper beach rocks on upper beach. Water covered in acorn temperature was 14°C. barnacles and stunted rockweed. Extensive eelgrass bed subtidally. 49

Table 2. cont'd.

Beach Area Slope Substrate Remarks No. (ha)

Kildidt Sound

1 0.1 Moderate. Sand/gravel. Watt Bay 1 (51°49.92'N, (0.1) Bedrock and 128°07.79'W). Live butter, littleneck, boulders at high softshell, cockle, pointed macoma and water margins green false-jingle collected; shell of all covered in acorn common. Moonsnails common; live barnacles and snails, egg collars and drilled stunted clamshell abundant. Black-clawed rockweed. and porcellanid crabs abundant under Eelgrass bed rocks. Water temperature was 15°C. below low tide line. 2 0.2 Low. Beach divided Watt Bay 2 (51°50.12'N, (0.1) by weir into 128°06.66'W). Live butter, littleneck, upper and lower softshell and bent-nose macoma portions. Upper collected; shell of cockle present. portion Several very old, eroded Manila shells sand/mud, lower found, one old Olympia oyster shell portion found. Red turbans, blue mud shrimp sand/shell. and black-clawed crabs present. Bedrock and Water temperature was 15°C. boulder margins covered sparsely with acorn barnacles and stunted rockweed, eelgrass bed below low tide line. 50

Table 2. cont'd.

Beach Area Slope Substrate Remarks No. (ha)

Kildidt Sound (cont'd)

3 0.3 Low to Beach divided Watt Bay 3 (51°50AO'N, (0.2) steep. into three 128°06.20'W). Live butter and poritions: lower littleneck on lower beach; live butter, beach very littleneck, softshell, Baltic, pointed small, and bent-nose macomas in middle sand/gravel lagoon; live green false-jingles and substrate; middle Olympia oysters in upper lagoon. lagoon with Live Manila clams and shells in all stream flowing three portions. Shell of horse (T. through and capax) present on lower beach, cockle gravel/sand shell present on lower beach and substrate; and middle lagoon. Acorn barnacles and upper lagoon limpets found on rocks in all three primarily rocky portions. Water temperature was 17°C with some in upper lagoon, 15°C at lower beach. sand/gravel. 4 <0.1 Moderate. Sand/gravel with Goodlad Bay (51 °52.96'N, «0.1) boulders at high 128°09AO'W). Live Manila and tide line covered littleneck collected, shell ofbutter, in acorn littleneck, Manila, softshell, cockle barnacles, lower and pointed macoma present. Manila margin of beach shell relatively scarce, few live dropped off Manilas at rock line on middle of quickly, sparse beach. Water temperature was 15°C. eelgrass present. 5 <0.1 Low. Gravel/sand with Stewart Inlet (51 °53.73'N, «0.1) heavy algal 128°07.37'W). Live Manila, butter, cover. Rocks on littleneck and cockle observed, shell of mid- to upper all common. Beach largely flooded by beach sparsely incoming tide, Manilas near rock line covered with at mid-beach. Water temperature was acorn barnacles. 17°C. 51

Table 2. cont'd.

Beach Area Slope Substrate Remarks No. (ha)

Broughton Strait

1 >10.0 Low. Gravel/sand with Cluxewe River estuary (500 37.3'N, (>10) some sandbars at 127°1O.90'W). Extensive beach mouth of river. extending north and south of the River channel Cluxewe River. Live butters found in divides to cross scratches; shell of butters common, beach at several shell of littleneck and cockle present. locations, Newly settled Dungeness crabs channels and common in sandy substrate, red rock sandbars appear crabs observed at low tide line. No to change live Manila or varnish clams or shell regularly; very were found. Water temperature was dynamic beach 13°C. at river mouth. 52

2 Table 3. Clam densities (clams m- ) by species from exploratory intertidal bivalve surveys in British Columbia, June 2004.

Butter Littleneck Manila Beach Quadrat Legal Sublegal Legal Sublegal Legal Sublegal Horse Macoma Softshell Cockle Varnish

Smith Sound

I 4.0 8.0 48.0 24.0 8.0 0.0 0.0 0.0 0.0 0.0 0.0 2 0.0 0.0 8.0 20.0 32.0 8.0 0.0 0.0 4.0 0.0 0.0 3 37.0 4.0 6.0 1.0 0.0 0.0 0.0 2.0 9.0 0.0 0.0 3 I 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 72.0 0.0 0.0 2 4.0 40.0 28.0 0.0 0.0 0.0 0.0 0.0 4.0 0.0 0.0

Rivers Inlet

I 24.0 352.0 112.0 20.0 0.0 0.0 4.0 20.0 4.0 0.0 0.0 2 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 52.0 0.0 0.0 3 I 44.0 26.0 15.0 4.0 0.0 0.0 0.0 17.0 0.0 17.0 0.0 4 I 20.0 304.0 68.0 112.0 0.0 0.0 48.0 0.0 0.0 52.0 0.0

Burke Channel

1 1 0.0 0.0 0.0 0.0 0.0 0.0 0.0 40.0 0.0 0.0 0.0 1 2 48.0 8.0 4.0 0.0 0.0 0.0 8.0 0.0 0.0 12.0 0.0 2 1 19.0 0.0 16.0 1.0 0.0 0.0 0.0 56.0 0.0 5.0 0.0 3 I 16.0 0.0 24.0 0.0 0.0 0.0 0.0 8.0 0.0 12.0 0.0 4 I 88.0 92.0 4.0 16.0 0.0 0.0 24.0 0.0 0.0 0.0 0.0

South Bentinck Arm

0.0 0.0 0.0 0.0 0.0 0.0 0.0 2,377.8 0.0 0.0 0.0

Roscoe Inlet

3 1 0.0 0.0 0.0 0.0 3.2 8.0 0.0 0.0 0.0 0.0 0.0 3 2 0.0 0.0 0.0 0.0 5.0 10.0 0.0 0.0 0.0 0.0 0.0 3 3 0.0 0.0 0.0 0.0 2.0 16.0 0.0 0.0 0.0 0.0 0.0 3 4 0.0 0.0 0.0 0.0 2.0 14.0 0.0 0.0 5.0 0.0 0.0 3 5 0.0 0.0 0.0 0.0 4.0 24.0 0.0 0.0 0.0 0.0 0.0 3 6 0.0 0.0 0.0 0.0 0.0 4.0 0.0 0.0 0.0 0.0 0.0 3 7 0.0 0.0 0.0 0.0 4.0 0.0 0.0 0.0 0.0 0.0 0.0 3 8 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 56.0 0.0 0.0 3 9 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 3 10 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 3 11 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 3 12 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0

Port B1ackney

1 I 0.0 0.0 0.0 0.0 20.0 20.0 0.0 0.0 0.0 0.0 0.0 1 2 0.0 0.0 0.0 0.0 12.0 4.0 0.0 0.0 0.0 0.0 0.0 1 3 0.0 0.0 8.0 16.0 8.0 0.0 0.0 4.0 0.0 0.0 0.0 1 4 0.0 0.0 4.0 0.0 16.0 0.0 0.0 0.0 0.0 0.0 0.0 1 5 2.0 0.0 8.0 22.0 10.0 2.0 0.0 10.0 0.0 0.0 0.0 1 6 0.0 0.0 0.0 0.0 88.0 32.0 0.0 16.0 24.0 0.0 0.0 2 1 0.0 0.0 0.0 0.0 10.0 4.0 0.0 0.0 26.0 0.0 0.0 2 2 0.0 0.0 0.0 0.0 6.0 5.0 0.0 0.0 6.0 0.0 0.0 2 3 0.0 0.0 0.0 0.0 4.0 12.0 0.0 0.0 12.0 0.0 0.0 2 4 0.0 0.0 0.0 0.0 8.0 4.0 0.0 0.0 0.0 0.0 0.0 3 1 17.0 5.0 1.0 0.0 1.0 1.0 1.0 0.0 0.0 1.0 0.0 3 2 0.0 16.0 8.0 48.0 240.0 36.0 0.0 0.0 0.0 0.0 0.0 3 3 8.0 40.0 24.0 16.0 48.0 0.0 0.0 0.0 0.0 0.0 0.0 3 4 0.0 0.0 0.0 16.0 164.0 36.0 0.0 4.0 0.0 0.0 0.0 3 5 0.0 0.0 0.0 0.0 12.0 8.0 0.0 16.0 4.0 0.0 0.0 3 6 4.0 12.0 16.0 0.0 8.0 0.0 0.0 8.0 0.0 0.0 0.0 53

Table 3. cont'd.

Butter Littleneck Manila Beach Quadrat Legal Sublegal Legal Sublegal Legal Sublegal Horse Macoma Softshell Cockle Varnish

Tolmie Channel

II 6.0 6.0 34.0 11.0 0.0 0.0 0.0 13.0 0.0 0.0 0.0 2 I 13.0 3.0 2.0 0.0 0.0 0.0 0.0 0.0 0.0 5.0 0.0 3 I 94.0 90.0 35.0 7.0 0.0 0.0 2.0 0.0 0.0 3.0 0.0 4 I 156.0 8.0 36.0 0.0 0.0 0.0 0.0 4.0 0.0 4.0 0.0 4 2 30.0 0.0 8.0 0.0 0.0 0.0 0.0 2.0 0.0 6.0 0.0 5 I 0.0 120.0 64.0 196.0 0.0 0.0 00 12.0 0.0 28.0 0.0

Spider Anchorage

1 1 2.0 3.0 1.0 0.0 0.0 0.0 0.0 0.0 22.0 0.0 0.0 I 2 48.0 8.0 0.0 0.0 0.0 0.0 4.0 4.0 0.0 0.0 0.0 4 I 28.0 0.0 5.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 6 0.0 3.0 13.0 2.0 19.5 1.0 0.0 0.5 0.0 0.5 0.0

Kildidt Sound

II 16.0 88.0 64.0 8.0 0.0 0.0 0.0 0.0 0.0 12.0 0.0 1 . 2 16.0 104.0 12.0 16.0 0.0 0.0 0.0 4.0 0.0 8.0 0.0 54

Table 4. Date, time and location of plankton tows conducted during exploratory intertidal bivalve surveys, June 2004.

Area Location Date Start Time Duration

Smith Sound Takush Harbour June 3 0955 5 min. (51°17.04'N,127°34.48'W) Rivers Inlet Darby Channel June 4 0615 5 min. (51°39.95'N, 127°40.92'W) Rivers Inlet Kilbella Bay June 5 0740 5 min. (51°41.27'N,127°21.25'W) Burke Channel Opposite Hvidsten Point June 6 1150 5 min. (51°57.96'N, 127°44.95'W) South Bentinck Taleomy Narrows June 7 1120 5 min. Arm (52°00.27'N,126°41.13'W) Dean Channel SW ofElcho Harbour June 8 1205 5 min. (52°19.97'N,127°27.29'W) Roscoe Inlet Ripley Bay June 9 1340 5 min. (52°25.36'N, 127°53.29'W) Port Blackney Oliver Cove June 14 0715 5 min. (52°18.74'N,128°21.18'W) Tolmie Channel Tolmie Channel June 15 0720 5 min. (52°42.69'N, 128°32.80'W) Tolmie Channel Flat Point June 16 0840 5 min. (52°58.59'N, 128°30.80'W) Kildidt Sound Stewart Inlet June 18 0950 5 min. (51°53.65'N, 128°07.29'W) 55

4,500 $9.0

4,000 $8.0

3,500 $7.0 3,000 $6.0 -r:: .t:::.- O" -~ 2,500 $5.0 -(I)- c '6 'E c 2,000 $4.0 ctl -G) -l ca:::s 1,500 $3.0 > 1,000 $2.0

500 $1.0

0 $0.0 70 75 80 85 90 95 00 Year 1--- Butter -+- Littleneck -+- Manila""*" Razor -e- Value I

Figure 1. Landings (t) and value ($Cdn) of intertidal clams from British Columbia commercial fisheries, 1970·2001. 56

120

100

80 ..-.. .::::... en Ol c: 60 :ac: Cl1 ....J 40

20

o 92/93 93/94 94/95 95/96 96/97 97/98 98/99 99/00 00101 01/02 02/03 Season

Figure 2. Landings of Manila clams (t) from Pacific Fisheries Management Area 7, 1992/1993 to 2002/2003 seasons. 57

Queen Charlotte Sound

Figure 3. General location of exploratory intertidal bivalve surveys in British Columbia, June 2-19, 2004. Legend: 1 - Smith Sound; 2 - Rivers Inlet; 3 - Burke Channel; 4 - South Bentinck Arm; 5 - Dean Channel; 6 - Roscoe Inlet; 7 - Port Blackney; 8 - Tolmie Channel; 9 - Spider Anchorage; 10 - Kildidt Sound; 11 - Broughton Strait. 58

Figure 4. Locations of beaches surveyed in Smith Sound, June 3, 2004.

Legend: 1 - Indian Island; 2 - Fly Basin; 3 - Broad Bay; 4 - North Side of Greaves Island. 59

10 -,------,

8-1------1

~ 6-1------1 c CD ::::lc:r ~ LL 4 +------1------.------1

2+------..-

O-h-rrrn"l-rrrTTTTTTTTTTTTTTTTTTTTTTTT-rrri"r-rnTTTT-I'r-n 10 20 30 40 50 60 70 80 90 100 110 120 Length (mm)

10

8

~ 6 c CD ::::lc:r ~ LL 4 -

2 -

o U II o 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 No. of Annuli

Figure 5. Length (top) and age (bottom) frequency distributions of butter clams collected at Indian Island, Smith Sound, June 3, 2004. 60

5-.------,

4+------1

>.3+------1 o c: (]) ::J C'" ~ L1.2-J------.------l

1 -J------

o +rrrrrrrTTTTTTTTTTTTrrTTTTl-r1 10 20 30 40 50 60 70 80 90 100 110 120 Length (mm)

5-.------,

4+------....,.------1

>. 3 +------1II1II­ o c: (]) ::J C'" ~ L1. 2 +------1II1II-

1 +------1II1II-

o 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 No. of Annuli

Figure 6. Length (top) and age (bottom) frequency distributions of butter clams collected in Broad Bay, Smith Sound, June 3, 2004. 61

100

90 ~ 80 /~ 70 -E -...-.E 60 / .s::..... /~ Ol c 50 (J) -l C co 40 / (J) :::2: 30 f

20 I 10 -J 0 o 12345678910 11 12 13 14 15 16 17 18 19 20 Annulus

Figure 7. Mean length-at-annulus of butter clams collected at Indian Island, Smith Sound, June 3, 2004. Error bars are 95% confidence intervals. 62

10 -,------,

8+------1

~ 6 +------1 c:: OJ ::Jc- ~ LL 4 +------1--,.------1

2+------.r-.---I-----.rH--..------I

O+-r...... -r--.-r...... -r--.-rr-A"r-r-...... -r..-r"'r-A..-r"',..,.,..,..,.r"Y"r..".r--ro'....roo.,.,...... "...... -rr-rrr..,..,.-,c-r-r--,----,,---.-r-rl 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 Length (mm)

10 -,------,

8+------

~ 6 +------c:: OJ ::Jc- ~ LL 4 +------

2+------

o +------r--,- o 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 No. of Annuli

Figure 8. Length (top) and age (bottom) frequency distributions oflittleneck clams collected at Indian Island, Smith Sound, June 3, 2004. 63

5.,.------,

4+------/

>-3+------/ (,) c (J) ::l C" ~ lL2+------.------/

1+------..----..-.rlI--..-.,.------j

O+-r-",-.-rr-rr-.-rr-rr-.-r",---.r",---.r",",--,--,-",-r"r"Y"r-T-r"r"'r--r-o--'--'-TTl---rTTTl---rT.--n---rT.--n---rT,.,--,rr1 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 Length (mm)

5

4

(,)>-3 c (J) ::l C" ~ lL 2 -

1 ;-- i--

o o 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 No. of Annuli

Figure 9. Length (top) and age (bottom) frequency distributions of littleneck clams collected in Broad Bay, Smith Sound, June 3, 2004. 64

5.,-~~~~~~~~~~~~~~~~~~~~~~~~~~~----,

4-t-~~~~~~~~~~~~~~~~~~~~~~~~~~~-I

(;'3-l-~~~~~~~~~~~~~~~~~~~~~~~~~~~--1

C Q) :::l 0- ~ LL.2-l-~~~~~~~~~~~~~~~~~~~~~~~~~~~--1

1+-~~~~~~~~~...... ---..--.n"...--

O+-r-rrr-rrrrr.."-.,.,.,---,-r.,.,.,---,-r,,,'Y"r"""-T'Y''r''nn-r 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 Length (mm)

5

4

(;' 3 c Q) :::l 0- ~ LL. 2 - .--

1 - - - l- I-

o o 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 No. of Annuli

Figure 10. Length (top) and age (bottom) frequency distributions of Manila clams collected at Indian Island, Smith Sound, June 3, 2004. 65

70

60

50 r/ E E ~ :;; 40 Cl /~ -C ~ c 30 ell Ql ::2: 20 I

10 / i o o 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Annulus

80

70 V t--' 60 150 T~ :5 ~ g> 40 ~ c ~ 30 Y ::2: 20 Y

10 /~ o o 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Annulus

Figure 11. Mean length-at-annulus of live Manila clams (top) and dead Manila shell (bottom) collected at Indian Island, Smith Sound, June 3, 2004. Error bars are 95% confidence intervals. 66

5.,------,

4+------j

»3+------1 () c:: Q) ::J C" ~ 1L2+------1

1-1------r----,,-...,,-....-...-.--.--..----,.------I

O+r-r-rTTTrrrTTTTTTTTTTTTTTTT1..,.,-,-rTTTrTTTTTTTTTTT-rrl'rTTTTTTTTTTT1~rhrrl'l'r-~n"rr-l'n-rTTT1TTTlI'n-r-TTTTTTTTTTTTTTT"1 10 20 30 40 50 60 70 80 90 100 110 120 Length (mm)

5

4

»3() c:: Q) ::J C" ~ 1L 2

1 - - ~ - - ~

o o 2 3 4 5 6 7 8 9 10 11 12 13 14 15 No. of Annuli

Figure 12. Length (top) and age (bottom) frequency distributions ofsoftshells collected at Indian Island, Smith Sound, June 3, 2004. 67

5.------,

4+------1

>.3+------1 (.) c (]) :::J 0- ~ ll..2+------,,----.------,,------1

O+rrrn-r-rrrrTTTT,.,.,..-r-",-/'n"n-l'rn'TT"i 10 20 30 40 50 60 70 80 90 100 110 120 Length (mm)

10

8

~ 6 c (]) :::J 0- ~ ll.. 4 r--

2 f-- - - -

o o 2 3 4 5 6 7 8 9 10 11 12 13 14 15 No. of Annuli

Figure 13. Length (top) and age (bottom) frequency distributions ofsoftshells collected in Broad Bay, Smith Sound, June 3,2004. 68

120

100

E 80 E '-' J:: C> c 60 3

~ 40

20

0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Annulus

120

100 ~ E 80 E -J:: r____ / C> c 60 3 /i ! 40

20 / rf

0 o 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Annulus

Figure 14. Mean length-at-annulus ofsoftshells collected at Indian Island (top panel) and Broad Bay (bottom panel), Smith Sound, June 3, 2004. Error bars are 95% confidence intervals. 69

Figure 15. Location of beaches surveyed in Rivers Inlet, June 4·5, 2004.

Legend: 1 - Head of Klaquaek Channel; 2 - Penrose Island North; 3 - Fury Island; 4 ­ Big Frypan Bay; 5 - Taylor Bay; 6 - Kilbella Bay; 7 - Whannock River estuary. 70

15 -,------,

12 -j------I

G 9 -j------L------I c Q) ::l 0" ~ u. 6 -1------

3+------....----

O+n-TTTTTTTTTTTTTTTTTTTTTTTT"T"Tf1"rr; 10 20 30 40 50 60 70 80 90 100 110 120 Length (mm)

35

30

25

Gc 20 Q) ::l 0" ~ u. 15

10 -

5 -

o I .. o 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 No. of Annuli

Figure 16. Length (top) and age (bottom) frequency distributions of butter dams collected at the head of Klaquaek Channel, Rivers Inlet, June 4, 2004. 71

5

4

>. 3 () c: Q) :::l C" ~ LL 2

1 f-

o "rr; 10 20 30 40 50 60 70 80 90 100 110 120 Length (mm)•

10

8

~ 6 c: Q) :::l C" ~ LL 4

2

o II o 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 No. of Annuli

Figure 17. Length (top) and age (bottom) frequency distributions of butter clams collected at Fury Island, Rivers Inlet, June 4, 2004. 72

10 .,------,

8+------1

~ 6 +------..-1------1 c (]) ::J 0- ~ LL 4 +------.,,-,,-

2+------.-.-...... ---.-

20 30 40 50 60 70 80 90 100 110 120 Length (mm)

20

16

>- 12 () c (]) ::J 0- ~ LL 8

4 -

o • o 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 No. of Annuli

Figure 18. Length (top) and age (bottom) frequency distributions of butter clams collected in Big Frypan Bay, Rivers Inlet, June 4,2004. 73

120

100

...... I E 80 E "-' ..c:..... 0) ~ c 60 (]) .....J Cco (]) ~ 40 /

20 I I o o 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Annulus

Figure 19. Mean length-at-annulus of butter clams collected at Fury Island, Rivers Inlet, June 4, 2004. Error bars are 95% confidence intervals. 74

10

8

5' 6 c Ql :::J C" ~ LL 4

2

o II 1111 II I 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 Length (mm)

20

16

>- 12 o c Ql :::J C" ~ LL 8 l-

4 f----- I---

o • o 2 3 4 5 6 7 8 9 10 11 12 13 14 15 No. of Annuli

Figure 20. Length (top) and age (bottom) frequency distributions oflittleneck clams collected at the head of Klaquaek Channel, Rivers Inlet, June 4, 2004. 75

5.------,

4+------1

>,3+------..------1 (.) c: OJ ::l 0- ~ LL2-j------,.,------h...... ------j

O-+--r-.,-,-,-,-,-.,-,-,-,-,-.,...-,---.r-.-r-1"..,.'r-t"'1rrr..,.."IIr-T-,--,-,--,-,--,--,-""'''''''''''''''''''',-,I",---I"r-h-r."--,.---".,,--,.---,,.,,--r-r-i 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 Length (mm)

10

8

~ 6 c: OJ ::l 0- ~ LL 4

2 c-- --

o 1I o 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 No. of Annuli

Figure 21. Length (top) and age (bottom) frequency distributions oflittleneck clams collected at Fury Island, Rivers Inlet, June 4,2004. 76

10

8

2

o I I II I I 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 Length (mm)

20

16

>- - o 12 s:: Q) ::l .l!:!0" u.. 8 -

4 r-- - r--

o • • o 2 3 4 5 6 7 8 9 10 11 12 13 14 15 No. of Annuli

Figure 22. Length (top) and age (bottom) frequency distributions of littleneck clams collected in Big Frypan Bay, Rivers Inlet, June 4,2004. 77

80

70

60 ~~ -II I 50 ..c---- g> 40 / j c:: ~ 30 / :2: /. 20

10 / rI o o 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Annulus

Figure 23. Mean length-at-annulus oflittleneck clams collected at Fury Island, Rivers Inlet, June 4, 2004. ' Error bars are 95% confidence intervals. 78

5..------,

4+------1

>.3+------1 () s::: Q) c:r::J ~ U.2+------,,----.------1

1+------..----.--.rl--..--rl-

O-l-rr-rTTTrTTTTTTTTTTT""""""T"T"nCTTT""rrrrl'rrrrl'r-l''n''rrrllr-r-r''r-l'rr 10 20 30 40 50 60 70 80 90 100 110 120 Length (mm)

10

8

~ 6 s::: Q) c:r::J ~ u. 4

2 I- ~ -

o L 1I o 2 3 4 5 6 7 8 9 10 11 12 13 14 15 No. of Annuli

Figure 24. Length (top) and age (bottom) frequency distributions of softshells collected at the head of Klaquaek Channel, Rivers Inlet, June 4, 2004. 79

80

70 ~ 60 y 150 .s:: ~ 40 / ~ c: ~ 30 I ~

20 / ( 10 o o 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Annulus

Figure 25. Mean length-at-annulus ofsoftshells collected at the head of Klaquaek Channel, Rivers Inlet, June 4, 2004. Error bars are 95% confidence intervals. 80

5

4

>.o 3 t: Q) :J C" ~ LL 2

1

o li 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 Height (mm)

15

12

~ 9 t: Q) :J C" ~ LL 6 l- I-

3 -- l- I- -

o o 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 No. of Annuli

Figure 26. Height (top) and age (bottom) frequency distributions ofcockles collected at Fury Island, Rivers Inlet, June 4, 2004. 81

100

80

..-.. ~ E / E 60 1.---" -..c 1 C) -c: Q) ...J c: Cll 40 Q) 7 ~ I~ 20 I o o 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Annulus

Figure 27. Mean height-at-annulus ofcockles collected at Fury Island, Rivers Inlet, June 4, 2004. Error bars are 95% confidence intervals. 82

Fitz Hugh ~ ~ Sound

127'55~

Figure 28. Location of beaches surveyed in Burke Channel, June 6, 2004.

Legend: 1 - Edmund Point; 2 - Fougner Bay; 3 - King Island 1; 4 - King Island 2. 83

5.------,

4-1------1

>.3+------,,------1 () s:::

1+------.-..------B--I---h-

O--h-rITTTTTTTrrn_TTTI"T1T1TTT1rrrrrTTTlTTT~'r-rrrrrn_TTTTTTTI"T1T1--n"nrr!'r-rHn 10 20 30 40 50 60 70 80 90 100 110 120 Length (mm)

5

4

>. 3 () s:::

1 I--

o o 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 No. of Annuli

Figure 29. Length (top) and age (bottom) frequency distributions of butter clams collected at Edmund Point, Burke Channel, June 6, 2004. 84

5

4

>, 3 () c: Q) :J 0- ~ LL 2

1

o ] 10 20 30 40 50 60 70 80 90 100 110 120 Length (mm)

10

8

~ 6 c: Q) :J 0- ~ LL 4

2

o I o 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 No. of Annuli

Figure 30. Length (top) and age (bottom) frequency distributions of butter clams collected in Fougner Bay, Burke Channel, June 4, 2004. 85

5-,------,

4+------.-----,.------1

3-1------1-----+------\ C/l .=! ::l c: «c: 2-1------.----.--

o -h-rrrrr-rrrr-rrrr-n"rrn"rrf"TT!ll'r­ 10 20 30 40 50 60 70 80 90 100 110 120 Length (mm)

10

8

()' 6 c: Q) ::l C" ~ u. 4 -

2

o I I o 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 No. of Annuli

Figure 31. Length (top) and age (bottom) frequency distributions of butter clams collected at King Island 2, Burke Channel, June 4, 2004. 86

100 ..,------,

80

E S 60 .c: 'E> c: Q) ...J c:co 40 Q) ::2

20

o 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Annulus

100 ..,------~------,

80

E S 60 .c: 'E> c: Q) ...J c:co 40 "Q) ::2

20

o 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Annulus

Figure 32. Mean length-at-annulus of butter clams collected at Edmund Point (top) and in Fougner Bay (bottom), Burke Channel, June 6, 2004. Error bars are 95% confidence intervals. 87

100 .,------,

80

E -S 60 ~ "5 c: Q) ..J c: ctS 40 Q) :2

20

o 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Annulus

100 .,------,

80

E -S 60 ~ -c:Ol Q) ..J c: ctS 40 Q) :2

20

o 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Annulus

Figure 33. Mean length-at-annulus of butter clams collected at King Island 1 (top) and King Island 2 (bottom), Burke Channel, June 6, 2004. Error bars are 95% confidence intervals. 88

5-r------,

4+------1

>.3-1------.------1 o I: Q) :::J C" ~ LL2-1------...---.--I---...------I

1-1------..------..-I1--I--h-I1--.--.-,....---.,..------I

0+r-T"""TT..-rr-r-,--,rr-r-,--,rr-rc-r"'r-rr-rrT"Trr-rn"r''n 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 Length (mm)

10

8

~ 6 I: Q) :::J C" ~ LL 4 c--

2 I-- -

o L o 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 No. of Annuli

Figure 34. Length (top) and age (bottom) frequency distributions of littleneck clams collected in Fougner Bay, Burke Channel, June 6, 2004. 89

80

70

60 I I 50 .s::--- ~i g> 40 .5 c ~ 30 / ::2: 20 /

10 / .,f o o 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Annulus

Figure 35. Mean length-at-annulus ofdead Manila clam shell collected at Edmund Point, Burke Channel, June 6, 2004. Error bars are 95%confidence intervals. 90

Figure 36. Location ofbeaches surveyed in South Bentinck Arm, June 7, 2004.

Legend: 1 - Head of South Bentinck Ann; 2 - Bentinck Narrows; 3 - Taleomy Narrows. 91

50

40 f--- -

>. 30 f--- - () c: Q) :::l 0- ~ LL 20 '--- - I-

10 ~ - I- - l- f--- I-

o LI-.L • 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Length (mm)

150 ,------,

120 -j------.

~ 90+------c: Q) :::l 0- ~ LL 60+------

30 +------

o +------r-- o 1 2 3 4 5 No. of Annuli

Figure 37. Length (top) and age (bottom) frequency distributions ofBaltic macomas collected at the head ofSouth Bentinck Arm, June 7, 2004. 92

50

40

~ 30 c (]) ::J 0" ~ LL 20

10 -

o I I I I II Ia I III r [ r I U. 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Length (mm)

!IIAge 1 o Age 2 ~Age 3 IIAge 4\

Figure 38. Length frequency by age class of Baltic macomas collected at the head of South Bentinck Arm, June 7, 2004. 93

Figure 39. Location of beaches surveyed in Dean Channel, June 8, 2004.

Legend: 1 - Elcho Harbour; 2 - King Island 3. 94

5

4

~ 3 c: Q) c:r:J ~ Li. 2

I" 1 mr o I 10 20 30 40 50 60 70 80 90 100 110 120 Length (mm)

10

8

~ 6 c: Q) :J c:r ~ Li. 4 l- I-

2 l- I- l- I- I-

o o 2 3 4 5 6 7 8 9 10 11 12 13 14 15 No. of Annuli

Figure 40. Length (top) and age (bottom) frequency distributions ofsoftshells collected in Elcho Harbour, Dean Channel, June 8, 2004. 95

100 ,------,

80

-E E 60 -..c Ol -C Q) ...J C ttl 40 Q) :2

20

0+-~,____,-_,__-r_____,-___,_-r_____,-_,__-r_____,-___,_-r_____,-___,__1 o 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Annulus

Figure 41. Mean length-at-annulus ofsoftshells collected in Elcho Harbour, Dean Channel, June 8, 2004. Error bars are 95% confidence intervals. 96

Figure 42. Location of beaches surveyed in Roscoe Inlet, June 9, 2004.

Legend: 1 - Clatse Bay; 2 - Shack Bay; 3 - Ripley Bay. 97

10

8

2

o IIIII 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 Length (mm)

25

20

- o>- 15 c: OJ ::l 0- ~ u. 10 f-- -

5 I- --

o o 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 No. of Annuli

Figure 43. Length (top) and age (bottom) frequency distributions of Manila clams collected in Ripley Bay, Roscoe Inlet, June 9, 2004. 98

80

70

60

I~ ~-l

20 /

10 / II o o 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Annulus

80

70

60

I ..... ~ ~

20 /

10 /

o " o 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Annulus

Figure 44. Mean length-at-annulus of Manila clams collected in Ripley Bay (top panel) and Manila clam shells collected in Clatse Bay (bottom panel), Roscoe Inlet, June 9, 2004. Error bars are 95% confidence intervals. 99

10.,------

8-1------j

~ 6 -I------.---,,------j l:: Q) :::s C" ~ u. 4 -I------t--I------j

2+------...... ------.--....----I---.r-1r-l----IIf------j

O-+rr-ITTTlTTTITTTTTTTTTTTTTTl''rr-n-TTTT-n"n-i'n"r..".{',-rn 10 20 30 40 50 60 70 80 90 100 110 120 Length (mm)

20 ..,------__,

15 +------

~ l:: ~ 10 +------C" ~ U.

5 -1------

o 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 No. of Annuli

Figure 45. Length (top) and age (bottom) frequency distributions ofsoftshells collected in Shack Bay, Roscoe Inlet, June 9, 2004. 100

5...,.------~------~------,

4+------~------~--1

>,3+------~-__j () c: Q) ::I C" ~ U.2+------.-----.....------__j

1+------.-..--...... --I----r--.-----..-----.--

O-h-rrrrrTTTTrrrrTTTTTTT1:-rrrrM-n"rrn"rrnl'r-r~'rrI'rTT1 10 20 30 40 50 60 70 80 90 100 110 120 Length (mm)

10

8

~ 6 c: Q) ::I C" ~ u. 4

2 ~ ~ ~ ~

o ~ o 2 3 4 5 6 7 8 9 10 11 12 13 14 15 No. of Annuli

Figure 46. Length (top) and age (bottom) frequency distributions ofsoftsheHs collected in Ripley Bay, Roscoe Inlet, June 9, 2004. 101

120

100

E 80 or T ...... E I .s:: C> l: 60 / ~

~ 40 /

20 / r/

0 o 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Annulus

120

100

E 80 g .s:: C> yrf l: 60 .... ~

~ 40 /

20 / r/

0 o 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Annulus

Figure 47. Mean length-at-annulus ofsoftshells collected in Shack Bay (top panel) and Ripley Bay (bottom panel), Roscoe Inlet, June 9, 2004. Error bars are 95% confidence intervals. 102

128'22'

Mathieson Channel

Powell Anohorage "- ~ "'------,.....-----.....IlI...... - ...... 128'22'l!l------.,..---128'21)'

Figure 48. Location of beaches surveyed in Port Blackney, June 14,2004.

Legend: 1 - Boat Inlet; 2 - Passage Cove; 3 - Oliver Cove. 103

5

4

G 3 c: OJ ::J 0- ~ LL 2

1 c-

o I T"TC 10 20 30 40 50 60 70 80 90 100 110 120 Length (mm)

15 --,------,

12 -j------j

G 9 c: OJ ::J 0- ~ LL 6-1------111------1

3 +------_IIIII_-----IIIIIIII---IIIIIII-_-

o 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 No. of Annuli

Figure 49. Length (top) and age (bottom) frequency distributions of butter clams collected in Oliver Cove, Port Blackney, June 14,2004. 104

100 --.------,

80

E .....-E 60 .J:: -OJ C (l) ...J C ('(j 40 (l) ~

20

o 12345678910 11 12 13 14 15 16 17 18 19 20 Annulus

Figure 50. Mean length-at-annulus of butter clams collected in Oliver Cove, Port Blackney, June 14, 2004. Error bars are 95% confidence intervals. 105

5.,.------,

4-!------..,------1

G 3 c::: OJ ::::l C" ~ u.. 2 -1------1-----0,----..-111----..--..------1

O+-r-,,--y-,--r,..,.-,-,--r.,--,--.--r''rr'''1''YY'rr'''1!''rr'''rr'''1''Y''r-,-,-,!''r-r.,--,rrr-,-,-,--.--r''r-T-rrr'-'-rTT'-'-rTT'-'-rTT,...,-rr-I 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 Length (mm)

10

8

G 6 c::: OJ ::::l C" ~ u.. 4

2 c-- - r-- -

o L LU o 2 3 4 5 6 7 8 9 10 11 12 13 14 15 No. of Annuli

Figure 51. Length (top) and age (bottom) frequency distributions of littleneck clams collected in Boat Inlet, Port Blackney, June 24, 2004. 106

5-,------,

4-1------..----..-----..------1

>, 3 -1------1--...... --1--11------1 () c: CD ::J 0" ~ lJ.. 2 -j------Jl----III-_._-11I------.,------1

O-h--r-r"'r---..''-r---I'''rrr-.''r-r'"n---..'"r''J''r'''r--r-,--,''Y'-r-,rr'Y"r''J''r'''r--r'''r--r..-r-r-rl 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 Length (mm)

10

8

() 6 - c: CD ::J 0" ~ lJ.. 4 ~ -

2 I- -- ~ - ~ -

o -.L o 2 3 4 5 6 7 8 9 10 11 12 13 14 15 No. of Annuli

Figure 52. Length (top) and age (bottom) frequency distributions of littleneck clams collected in Oliver Cove, Port Blackney, June 14,2004. 107

10

8

G 6 c Ql :::l C" ~ u.. 4

2

o II II II III I 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 Length (mm)

15

12

,- G 9 t-- c :::l Ql C" ~ u.. 6 - I-- '--- I-- t--

3 - t-- - 1- '--

o -J o 2 3 4 5 6 7 8 9 10 11 12 13 14 15 No. of Annuli

Figure 53. Length (top) and age (bottom) frequency distributions of Manila clams collected in Boat Inlet, Port Blackney, June 14, 2004. 108

5,------,

4+------j

»3+------..-.r------j () c (I) :::J 0- ~ u..2+------..-----...... ----I-I!I--...------1

O+rTTl---rT-rr"rr-r'Y"r-"""'-."r"t-r-r"rr'Y'r"-r'"T"T'''r''r''A-r-r'''r"rrr''-;-TTl---rT"rr-r-.--r-,--,-,rrr.,-;-,,--,-,--,,,-! 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 Length (mm)

10

8 -

~ 6 - c (I) :::J 0- ~ u.. 4 -

2 I-- r- - I--

o o 2 3 4 5 6 7 8 9 10 11 12 13 14 15 No. of Annuli

Figure 54. Length (top) and age (bottom) frequency distributions of Manila clams collected in Passage Cove, Port Blackney, June 14, 2004. 109

20

16

~ 12 c: OJ :::l cr ~ u. 8

4

o I II II I. III 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 Length (mm)

60

50

40 !-- >. (,) c: ~ - cr 30 ~ U.

20 r---- l-

10 I- '-- l-

o II LI o 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 No. of Annuli

Figure 55. Length (top) and age (bottom) frequency distributions of Manila clams collected in Oliver Cove, Port Blackney, June 14, 2004. 110

70

60

50 E E ~ :; 40 rnc: CIJ ~ / 30 ttl CIJ :2: 20 /

10 / .I

o o 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Annulus

70

60

50 E E ~ :; 40 rnc: CIJ ~ 30 / ttl CIJ :2: 20 /

10 I o " o 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Annulus

Figure 56. Mean lengthmatmannulus of Manila clams collected in Boat Inlet (top) and Passage Cove (bottom), Port Blackney, June 14,2004. Error bars are 95% confidence intervals. 111

70

60

50 E E ~ :;; 40 "5 c::: (]) ~ 30 / CIl (]) ::2 20 /

10 ,I o o 2 345 6 7 8 9 10 11 12 13 14 15 Annulus

Figure 57. Mean length-at-annulus of Manila clams collected in Oliver Cove, Port Blackney, June 14, 2004. Error bars are 95% confidence intervals. 112

5,------,

4+------1

>.3+------1 Q c: OJ ::J 0- ~ ll..2+------.------.------!

O+n-TTTT-rn"l"r-n-fTTT-I'rn-N'rrrrrTTTT-rn"l-l'rrn"r-rn"r-r-!'l'n-N'rrrrrrrn''r-rn 10 20 30 40 50 60 70 80 90 100 110 120 Length (mm)

10

8

~ 6 c: OJ ::J 0- ~ ll.. 4

2 ,.- I-- - - -

o .-L LI o 2 3 4 5 678 9 10 11 12 13 14 15 No. of Annuli

Figure 58. Length (top) and age (bottom) frequency distributions ofsoftshells collected in Passage Cove, Port Blackney, June 14, 2004. 113

120

100 V -E 80 E .c--- /i ..... 0> c 60 Q) -.J C co Q) :2 40 /

20 / Ill'

o o 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Annulus

Figure 59. Mean length-at-annulus of softshells collected in Passage Cove, Port Blackney, June 14, 2004. Error bars are 95% confidence intervals. 114

Figure 60. Location of beaches surveyed in Tolmie Channel, June 15-16, 2004.

Legend: 1 - Alexander Inlet; 2 - Brown Cove; 3 - Tolmie Channell; 4 - Tolmie Channel 2; 5 - Flat Point. us

5,------,

4-!------I

6 3 -t------.".------I s:: OJ ::J 0- ~ LL2-t------h---.------I

O-h-nrrn-rTTTTTTTTTTT-rrrr-.rr;""TTTlrrrnrrn-rrrrTTTTT"T"n 10 20 30 40 50 60 70 80 90 100 110 120 Length (mm)

10

8

2

o III o 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 No. of Annuli

Figure 61. Length (top) and age (bottom) frequency distributions of butter clams collected in Alexander Inlet, Tolmie Channel, June 15, 2004. 116

5--,------,

4--j------j

6 3 -I------,------j c (j) ::J c:r ~ LL2+------h-----.------1

1+------

O+n-TTTTrrrTrrTTTTTTTTTl-rrr1TTTTTTTTTTTlTTTrrTTTTTT 10 20 30 40 50 60 70 80 90 100 110 120 Length (mm)

10

8

2

o III I o 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 No. of Annuli

Figure 62. Length (top) and age (bottom) frequency distributions of butter clams collected in Brown Cove, Tolmie Channel, June 15, 2004. 117

15 -,------,

12 +------..------1

G 9 +------1------/ c OJ ::l 0- E! LL 6+------...,.------I-fl--h------/

3+------..-l1-lhr--..-

o -+rrrrN'rn"n 10 20 30 40 50 60 70 80 90 100 110 120 Length (mm)

35

30

25

Gc 20 OJ ::l 0- J: 15

10

5 -

o I11III I I o 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 No. of Annuli

Figure 63. Length (top) and age (bottom) frequency distributions of butter dams collected at Tolmie Channel 1, Tolmie Channel, June 15, 2004. 118

10,------,

8+------,------j

G 6 +------,,------j c:: CD :J 0- E:! 11. 4+------f-----f-H-....-.r----u------j

2+------h-

O--t-.rTITTTTTTTTTTTTTTTTTTOTTlOTTlOTTlOTTlcrn"-fTTT"n"n-f"TT"l"rn 10 20 30 40 50 60 70 80 90 100 110 120 Length (mm)

20

16

G 12 c:: CD :J 0- E:! 11. 8

4 -

o o 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 No. of Annuli

Figure 64. Length (top) and age (bottom) frequency distributions of butter clams collected at Tolmie Channel 2, Tolmie Channel, June 16, 2004. 119

5

4

>, 3 () c (]) ::::l 0-e: u. 2

r-

o T In- 10 20 30 40 50 60 70 80 90 100 110 120 Length (mm)

15

12

~ 9 c (]) ::::l 0-e: u. 6

3

o I o 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 No. of Annuli

Figure 65. Length (top) and age (bottom) frequency distributions of butter dams collected at Flat Point, Tolmie Channel, June 16, 2004. 120

100 .,------,

80

E ,§. 60 ..t: 0, c: OJ ...J c: ell 40 OJ ~

20

o 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Annulus

100 .,------,

80

E ,§. 60 ..t: 0, c: OJ ...J c: m 40 ~

20

o 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Annulus

Figure 66. Mean lengthaat-annulus of butter clams collected in Alexander Inlet (top) and Brown Cove (bottom), Tolmie Channel, June 15, 2004. Error bars are 95% confidence intervals. 121

100 -,------,

80

E -S 60 ..r::: OJ c (I) -l C CIl 40 (I) ~

20

2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Annulus

Figure 67. Mean length-at-annulus of butter clams collected at Tolmie Channell, Tolmie Channel, June 15,2004. Error bars are 95% confidence intervals. 122

100 -,------,

80

E 5 60 ..c 0, c OJ ....J Cco 40 OJ ::2:

20

o 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Annulus

100 -,------,

80

E 5 60 ..c 0, c OJ ....J Cco 40 "OJ ::2:

20

o 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Annulus

Figure 68. Mean lengthmatmannulus of butter dams collected in high density areas (top) and low density areas (bottom) of Tolmie Channel 2, Tolmie Channel, June 16, 2004. Error bars are 95% confidence intervals. 123

10

8

2

o 1111 I III 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 Length (mm)

25

20

G 15 c: OJ ::J cr l!! u. 10

5 I-- I-- l-

o • o 2 3 4 5 6 7 8 9 10 11 12 13 14 15 No. of Annuli

Figure 69. Length (top) and age (bottom) frequency distributions of littleneck clams collected in Alexander Inlet, Tolmie Channel, June 15, 2004. 124

10

8

2

o I 111111 II I 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 Length (mm)

15 ,------,

12 -t------

~ 9-+------c: Q) ::J C'" l!! u.. 6-+------

3-t------

o -1----,--,- o 2 3 4 5 6 7 8 9 10 11 12 13 14 15 No. of Annuli

Figure 70. Length (top) and age (bottom) frequency distributions of littleneck clams collected at Tolmie Channell, Tolmie Channel, June 15, 2004. 125

5--r------,

4+------j

>.3+------..------..------j () s:: Q) ::l 0- ~ Ll..2+------D-----.nr-l----..------j

1+------Ih-mrlH--I---.rlI-----..-----..------j

O+r-r-r-T.,..-,--.--.-r.,..-,--.--.-r-r-r..-r-r-r-r..-r-r-r-r..-r-r-r-r"...... ,""""'Y",-'l,-,JI',-""""'-,JI',-..--r"',--rr-r-r-rTT-.--r;rTT-r-r-r-r-r..-rr-I 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 Length (mm)

10

8

() 6 s:: Q) ::l 0- ~ Ll.. 4 l- I-

2 i- i-

o L o 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 No. of Annuli

Figure 71. Length (top) and age (bottom) frequency distributions oflittleneck clams collected at Tolmie Channel 2, Tolmie Channel, June 16, 2004. 126

10

8

2 II o III II 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 Length (mm)

20

16

>, 12 I-- () c: (1) :::J 0" ~ u. 8 I- -

4 - - I-- -- I--

o It o 2 3 4 5 6 7 8 9 10 11 12 13 14 15 No. of Annuli

Figure 72. Length (top) and age (bottom) frequency distributions of littleneck clams collected at Flat Point, Tolmie Channel, June 16, 2004. 127

.------'"""l128'14' 128'12' 128'10'

o 0.5 1 Km ~

Figure 73. Locations of beaches surveyed in Spider Anchorage, June 17, 2004.

Legend: 1-Huriicane Island 1; 2 - Hurricane Island 2; 3 - Hurricane Island 3; 4­ Hurricane Island 4; 5 - Hurricane Island 5; 6 - Hunter Island. 128

5,------,

4-1------1

~3-1------1 c Q) :Jc- ~ LL2-J------.------..----..,------1

O+r-r-rTTT"rrrrrrrrTTTTTTTTTrTl"""rTTT"I'rr-rTTTTrrI'r-n"r1'rr 10 20 30 40 50 60 70 80 90 100 110 120 Length (mm)

5

4

r-

1

o o 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 No. of Annuli

Figure 74. Length (top) and age (bottom) frequency distributions of butter clams collected at Hurricane Island 1, Spider Channel, June 17,2004. 129

5

4

>. 3 () c: (j) :J a- ~ LL 2 1111

1

o '" 10 20 30 40 50 60 70 80 90 100 110 120 Length (mm)

15

12

i:)' 9 c: (j) :J a- ~ LL 6 -

3 -

o •1 I •• o 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 No. of Annuli

Figure 75. Length (top) and age (bottom) frequency distributions of butter clams collected at Hurricane Island 4, Spider Anchorage, June 17, 2004. 130

100 ..,------,

80

E .S- 60 .c..., 0) c Q) .....I Cco 40 Q) :2

20

o 12345678910 11 12 13 14 15 16 17 18 19 20 Annulus

Figure 76. Mean length-at-annulus of butter clams collected in Spider Anchorage, June 17,2004. Error bars are 95% confidence intervals. 131

10

8

>. 6 o c Q) ::J 0' ~ LL 4

2

o I II I II 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 Length (mm)

10

8

>. 6 f-- - o c Q) ::J 0' ~ LL 4 f-- -

2 - ,...-- f-- - I--

o -J o 2 3 4 5 6 7 8 9 10 11 12 13 14 15 No. of Annuli

Figure 77. Length (top) and age (bottom) frequency distributions of littleneck dams collected at Hunter Island, Spider Anchorage, June 17, 2004. 132

10

8

2

o II II I II II 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 Length (mm)

20

16

>, 12 (,) l:: OJ ::::s 0- ~ u.. 8 - i--

4 - - i--

o II o 2 345 6 7 8 9 10 11 12 13 14 15 No. of Annuli

Figure 78. Length (top) and age (bottom) frequency distributions of Manila clams collected at Hunter Island, Spider Anchorage, June 17,2004. 133

80

70

60

I 50 ---.c ~ ~ 40 (]) ....J C ~ 30 / ::2: 20 I

10 I I o o 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Annulus

Figure 79. Mean Iength-at-annuIus of Manila clams collected in Spider Anchorage, June 17, 2004. Error bars are 95% confidence intervals. 134

5,------,

4-1------1

is 3-1------1 c OJ ::J 0- ~ U.2+------.------,.-----..----I

1+-----.------".------11'--,,------.---.-----.--....---.-.--,..-

O-trr-rTTTTTTT-/'rn-TlTTTTTl-rrnrTTTrTTTTTTTITTTTlTTTlTTTTTTTTl"'J-rrrrrn"n"rTTT1"rTT1"rn"rrTTTl"I'rI'J"rrrM-c 10 20 30 40 50 60 70 80 90 100 110 120 Length (mm)

10

8

~

2 ~ - l-

o LL LI o 2 3 4 5 6 7 8 9 10 11 12 13 14 15 No. of Annuli

Figure 80. Length (top) and age (bottom) frequency distributions ofsoftshells collected at Hurricane Island 1, Spider Anchorage, June 17,2004. 135

120 ,------,

100

80 .sE .c Ol -c 60 OJ ....J C tiS OJ :::iE 40

20

o 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Annulus

Figure 81. Mean length-at-annulus of softshells collected in Spider Anchorage, June 17,2004. Error bars are 95% confidence intevals. 136

Kildidt Sound

128'10'

Figure 82. Location of beaches surveyed in Kildidt Sound, June 18, 2004.

Legend: 1 - Watt Bay 1; 2 - Watt Bay 2; 3 - Watt Bay 3; 4 - Goodlad Bay; 5 - Stewart Inlet. 137

10 -,------

8 -1------1

~ 6+------..------1 c OJ :J 0- £I: LL 4+------

2 +------.-11-

o --\-n-;rrrn-n"n-n"n-rl'n-f'rn-rl'f'rTTTT-f'rN'rn 10 20 30 40 50 60 70 80 90 100 110 120 Length (mm)

20

16

>, 12 o c (l) ::s 0- ~ LL 8

4

o • 1. 1 I • o 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 No. of Annuli

Figure 83. Length (top) and age (bottom) frequency distributions of butter clams collected at Watt Bay 1, June 18, 2004. 138

80

70

60 vf-- 150 T~l .!: g 40 / ~ c: / ~*30 20 I 10 ,I o o 12345678910 11 12 13 14 15 16 17 18 19 20 Annulus

Figure 84. Mean length-at-annulus of butter clams collected at Watt Bay 1, Kildidt Sound, June 18, 2004. Error bars are 95% confidence intervals. 139

5,------,

4+------1

>.3+------1 o c:: (1) ::l 0- ~ l.L2-+------....---...--..-----.n..-...------!

O+-r-,.--"'''r-r-TT"T--.-r-r-r-r....,-,-.,..,,....,-,-r-r-r.....Y''r'"1..,..,.'r-r-o---r''r''r-r-o..,..,.Y''r'"1...... 'r-r--rTT.,,---rTT.,,---rTT.,,---rr-r.,,---~ 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 Length (mm)

10

8

Ei' 6 c:: (1) ::l 0- ~ l.L 4 I-- '---

2 I-- ~

o L.L LJ o 2 3 4 5 6 7 8 9 10 11 12 13 14 15 No. of Annuli

Figure 85. Length (top) and age (bottom) frequency distributions of littleneck clams collected at Watt Bay 1, June 18,2004. 140

10

8

G 6 c OJ ::J 0- ~ u.. 4

2

o I III II I II 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 Length (mm)

30

25

20

15 I-

10 I- 1-

5 r-- I- I- I- I-

o La o 2 3 4 5 6 7 8 9 10 11 12 13 14 15 No. of Annuili

Figure 86. Length (top) and age (bottom) frequency distributions of Manila clams collected in Kildidt Sound, June18, 2004. 141

70

60

50 / E E ~ 40 / lJ) -c Q) ....J 30 / c ell Q) ~ 20 /

10 / rI

o o 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Annulus

Figure 87. Mean length-at-annulus of Manila clams collected in Kildidt Sound, June 18, 2004. Error bars are 95% confidence intervals. 142

127'20' 127'15' 127'10' 127'5' 125'55'

Johnstone Strait

Figure 88. Location of beach surveyed in Broughton Strait, June 19, 2004.

Legend: 1 - Cluxewe River estuary. 143

Appendix 1. Common and scientific names of species recorded during exploratory intertidal bivalve surveys in British Columbia, June 2004.

Common name Scientific name Common name Scientific name

Bivalve Molluscs

Cockle (Nuttall cockle) Clinocardium nuttallii Softshell Mya arenaria Pacific oyster Crassostrea gigas Truncated softshell Mya truncata California sunsetclam Gari califomica Varnish clam (purple mahogany­ Nuttallia obscurata clam) Arctic hiatella Hiatella arctica Olympia oyster Ostrea conchaphila Kellyclam (suborbicular kellyclam) Kellia suborbicularis Green false-jingle Pododesmus macrochisma Baltic rnacoma Macoma balthica Littleneck clam (Pacific Protothaca staminea littleneck) Pointed macoma Macoma inquinata Butter clam (Washington Saxidomus gigantea butterclam) Bent-nose macoma Macoma nasuta Fat horse clam (fat gaper) Tresus capax White-sand macoma Macoma secta Pacific horse clam (Pacific gaper) Tresus nuttallii Fan horsemussel Modiolus rectus Manila clam (Japanese littleneck) Venerupis philippinarum Blue mussel Mytilus edulis complex Oblique-lined yoldia Yoldia seminuda California mussel Mytilus califomianus

Gastropods

Red turban Astraea gibberosa Dire whelk Lirabuccinium dirum Moonsnail Euspira lewisii Limpets Lottiidae Gumboot chiton Cryptochiton stelleri Striped dogwinkle Nucella emarginata Black katy chiton Katerina tunicata Frilled dogwinkle Nucella lamellose

Arthropods

Acorn barnacle Balanus glandula Porcelain crab Petrolisthes eriomerus Dungeness crab Cancer magister Thatched barnacle Semibalanus cariosus Red rock crab Cancer productus Blue mud shrimp Upogebia pugettensis Black-clawed crab Lophopanopeus bellus

Echinoderms

Tarspot cucnmber Cucumaria vegae Green sea urchin Strongylocentrotus droebachiensis Giant red cucumber Parastichopus califomicus

Cnideria

Giant green anemone Anthopleura Sea blubber Cyanea capillata xanthogrammica Aggregating green anemone Anthopleura Clinging jellyfish Gonionemus vertens elegantissima Moon jellyfish Aurelia labiata Giant plumose anemone Metridium giganteum

Plants

Rockweed Fucus gairdneri Sea lettuce Ulva jenestrata Dinoflagellate Noctiluca scintillans Eelgrass Zostera marina Broadleaf Kelp Lamineria sp.

Fish

Pacific sand lance Ammodytes hexapterus Flatfish Pleuronectidae Sculpins Cottidae Salrnonids Oncorhynchus sp.

Sources: Drueh12000; Harbo 1999; Lambert 1997, 2000; Turgeon et at. 1998; eoan et at. 2000. 144

Appendix 2. Data collection form used during exploratory intertidal bivalve surveys in British Columbia, June 2004.

Beach Data Form - Exploratory Intertidal Clam Survey

Date: Beach Name:

Time Surveyed: LatILong:

Total Beach Area (hal: Clam-bearing Area (hal:

Water Temp: Plankton tow:

Beach Slope:

Substrate:

No. of scratches: No. of guadrats:

Species: Live Shell Live Shell

Manila Littleneck

Butter Varnish

T.capax T. nuttallii

Softshell Cockle

M. balthica M. inquinata

M. nasuta M. secta

Oly. Oyster Pac. Oyster

Other species:

Remarks: