National Marine Fisheries Service U.S DEPARTMENT OF COMMERCE AFSC PROCESSED REPORT 94-03 Preliminary Report on the Genetic Diversity of Sockeye Salmon Populations from Southeast Alaska and Northern British Columbia July 1994 iis report does nor mnsutute a ppl nd is for inl ormafion only. 1 data herein are to h wndderm ~IUVEI~~a!. ERRATA NOTICE This document is being made available in .PDF format for the convenience of users; however, the accuracy and correctness of the document can only be certified as was presented in the original hard copy format. Inaccuracies in the OCR scanning process may influence text searches of the .PDF file. Light or faded ink in the original document may also affect the quality of the scanned document. PRJ%IMINARY REPORT ON THE GENETIC DIVERSITY OF SOCKEYE SALMON POPULATIONS FROM SOUTHEAST ALASKA AND NORTHERN BRITISH COLUMBIA C.M. Guthrie HI1, J.H. Helle1, l? Aebersold2, G.A. Wmans2, and A.J. GharrettU 'Auke Bay Laboratory Alaska Fisheries Science Center National Marine Fisheries Service National Oceanographic and Atmospheric Administration 1 1305 Glacier Highway, Juneau, Alaska 99801-8626 9orthwest Fisheries Science Center National Marine Fisheries Service National Oceanographic and Atmospheric Administration 2725 Montlake Boulevard East, Seattle, Washington 981 12 School of Fisheries and Ocean Sciences, University of Alaska Fairbanks, 11 120 Glacier Highway, a, , Juneau, Alaska 99801 July 1994 ABSTRACT Genetic data were collected and prepared with the use of protein electrophoresis from 52 spawning locations in southeastern Alaska and northern British Columbia. Genetic relationships were examined from principal components analysis and unrooted trees constructed from genetic distances between collections. These descriptive analyses suggest a geographic basis to genetic divergence among populations. This geographic basis was confirmed using log-likelihood-ratio analysis and analyses of variance. Three groups of populations were observed: one from systems that drain into the inside waters of northern and central southeast Alaska; another from the far southeastern islands (including Prince of Wales Island); and the third in systems of the southern inside waters. Although the geographic structure was a statistically significant component of the overall genetic structure, gene diversity analysis indicates that only about 4.7% of the total genetic variability was attributable to genetic differences among those regions, whereas about 8.4% of the total was due to differences among populations within each region. The other 87.0% of the variation occurred, on average, within each collection. v CONTENTS METHODS ANDMATERIALS ........................................... 1 Samples .......................................................... 1 Analysis ...................................................... 2 RESULTS ............................................................ 3 Genetic Description of the Collections ................................... 3 Pooling Adult Collections for Analyses ................................... 3 Taku River Juvenile Sockeye ........................................... 4 DescriptiveAnalysis ................................................. 5 Analysis of Geographic Structure ....................................... 6 EntryRoute ....................................................... 7 Effect of Rearing Habitat on Genetic Structure ............................ 8 GeneDiversityAnalysis .............................................. 8 5 DISCUSSION ....................................................... 9 RECOMMENDATIONS ................................................ 11 ACKNOWLEDGMENTS .> .............................................. 11 CITATIONS .......................................................... 13 TABLES .............................................................. 15 FIGURES ............................................................ 29 APPENDICES ........................................................ 39 TABLES Table 1.--Group designation (letters correspond to spawning areas listed in F'igs. 1,3-6 and appendices 1-3), location, collection date, and number of sockeye salmon (N), used for electrophoretic analysis. Districts are Alaska Department of Fish and Game statistical areas. .......................................................... 17 Bble 2.--Group designation (letters correspond to rearing areas listed in Fig. 2 and in Appendices 4-6), location, date of collection, and number of Tmku River juvenile sockeye salmon (N) used for electrophoretic analysis. ........................ 22 Table 3.-Buffer systems used for electrophoresis of Southeast Alaska and northern British Columbia sockeye salmon samples. ...................................... 23 Table 4.-Enzymes screened, their International Union of Biochemistry (IUBNC 1984) enzyme commission (EC) numbers and abbreviations. Peptidases are designated according to their substrate specificity. ................................... 24 Table 5.-Protein-coding loci (ShaMee et. al. 1990) for enzymes resolved in this study and the tissues and buffer in which they were resolved. Peptidase loci are designated according to their substrate specificity. The buffers are designated by the acronyms in Table 4. L = liver, H = heart, M = muscle, E = eye. ....................... 25 Table 6.-Hierarchical gene diversity analysis (Chakraborty and Leimar 1987) of Southeast Alaska sockeye populations. One analysis used data from 31 loci and included 25 collections, the other used 8 loci and included 47 collections. The additional collections in the latter analysis enabled use of an additional level of hierarchy, among collections taken at a sample site. ................................................ 28 Table 7.-Hierarchical gene diversity analysis (Chakraborty and Leimar 1987) of Taku River sockeye populations. bne analysis used data £rom 31 loci and the other used 8 loci. Additional collections in the latter analysis enabled use of an additional level of hierarchy, among collections taken at a sample site. ......................... 28 vii FIGURES Figure 1.-Alaska Department of Fish and Game statistical fishery districts, designated by threedigitcode..................................................... 31 Figure 2.Sampling sites for sockeye salmon in Southeast Alaska and northern British Columbia. Letters correspond to collection sites listed in Table 1, Figs. 4-7, and Appendices 1-3. Sites with multiple collections are designated by a single letter. ... 32 Figure 3.--Sampling sites for juvenile sockeye salmon on the Taku River drainage in Southeast Alaska and northern British Columbia. Letters correspond to collection sites listed in Table 2 and Appendix 4. ....................................... 33 Figure 4.-Principal component analysis of Southeast Alaska and northern British Columbia sockeye salmon for allelic frequency of 21-locus data set. Letters correspond to collection sites listed in Table 1, Figs. 2, 5-7, and Appendices 1-3. Circled letters within aggregations indicate collections not geographically associated with the aggregation. NSE = northern Southeast; SSE = southern Southeast. ............ 34 Figure 5.-Principal component analysis of Southeast Alaska and northern British Columbia sockeye salmon for the most common allele in a &locus data set. Letters correspond to collection sites listed in Table 1, Figs. 2, 5-7, and Appendices 1-3. Circled letters within aggregations indicate collections not geographically associated with the aggregation. ....................................................... 35 Figure 6.-Neighbor-joining tree (Saitou and Nei 1987) using genetic distances (CavalliSforza and Edwards 1%7) estimated from allelic frequencies at 31 loci. .... 36 Figure 7.-Neighbor-joining tree (Saitou and Nei 1987) using genetic distances (CavalliSforza and Edwards 1%7) estimated from allelic frequencies at 8 loci. Circled letters within aggregations indicate collections not geographically associated with the aggregation. ................................................ 37 APPENDIX Appendix 1.-Allozyme variation in collections of sockeye salmon from Southeast Alaska and northern British Columbia Allelic frequencies and collection sizes (N) are designated as in Bble 1. Alleles are designated by their mobility relative to the most common allele (*100) and as descrii in Shaklee et. aL (1990). Collections are pooled in accordance with Appendix 3. .......................................... 41 Appendix 24ample sizes of monomorphic loci .............................. 95 Appendix 3.-Log-likelihood ratio analysis comparisons of collections from the same site but at difEerent times. Where subdivision of samples at a site are made for subsequent analyses, both the total heterogeneity at the site and the heterogeneity within the subdivision are presented. The total includes the heterogeneity within and among collections at that site. A blank at a site (with a value for "betweenw)indicates one collectiononly. .................................................... 99 Appendix 4.-AUozyme variation in collections of juvenile sockeye salmon from the 'Ihlcu River in Southeast Alaska and northern British Columbia. AUelic frequencies and collection sizes (N) are designated as in nble 2. Alleles are designated by their mobility relative to the most common allele (*I@) and as descni in Shaklee et. al. (1990). .......................................................... 101 Appendix 5.-Log-likelihood ratio analysis (G-test) of the genetic heterogeneity