Single nucleotide polymorphisms (SNPs) are appealing genetic markers due to several beneficial attributes, but uncertainty remains about how many of these bi‐allelic markers are necessary to have sufficient power to differentiate populations, a task now generally accomplished with highly polymorphic microsatellite markers. In this study, we tested the utility of 37 SNPs and 13 microsatellites for differentiating 29 broadly distributed populations of Chinook salmon (n = 2783). Information content of all loci was determined by In and , and the top 12 markers ranked by In were microsatellites, but the 6 highest, and 7 of the top 10 ranked markers, were SNPs. The mean ratio of random SNPs to random microsatellites ranged from 3.9 to 4.1, but this ratio was consistently reduced when only the most informative loci were included. Individual assignment test accuracy was higher for microsatellites (73.1%) than SNPs (66.6%), and pooling all 50 markers provided the highest accuracy (83.2%). When marker types were combined, as few as 15 of the top ranked loci provided higher assignment accuracy than either microsatellites or SNPs alone. Neighbour‐joining dendrograms revealed similar clustering patterns and pairwise tests of population differentiation had nearly identical results with each suite of markers. Statistical tests and simulations indicated that closely related populations were better differentiated by microsatellites than SNPs. Our results indicate that both types of markers are likely to be useful in population genetics studies and that, in some cases, a combination of SNPs and microsatellites may be the most effective suite of loci.

An international multi-laboratory project was conducted to develop a standardized DNA database for Chinook salmon (Oncorhynchus tshawytscha). This project was in response to the needs of the Chinook Technical Committee of the Pacific Salmon Commission to identify stock composition of Chinook salmon caught in fisheries during their oceanic migrations. Nine genetics laboratories identified 13 microsatellite loci that could be reproducibty assayed in each of the laboratories. To test that the loci were reproducible among laboratories, blind tests were conducted to verify scoring consistency for the nearly 500 total alleles. Once standardized, a dataset of over 16,000 Chinook salmon representing 110 putative populations was constructed ranging throughout the area of interest of the Pacific Salmon Commission from Southeast Alaska to the Sacramento River in California. The dataset differentiates the major known genetic lineages of Chinook salmon and provides a tool for genetic stock identification of samples collected from mixed fisheries. A diverse group of scientists representing the disciplines of fishery management, genetics, fishery administration, population dynamics, and sampling theory are now developing recommendations for the integration of these genetic data into ocean salmon management.

Most of the variation (99%) of Asian odd‐broodline pink salmon Oncorhynchus gorbuscha, based on data at 32 variable (46 total) allozyme loci from 35 populations, occurred within populations. The remaining interpopulation variation was attributable to: (1) differences between northern (the northern Sea of Okhotsk, eastern Kamchatka Peninsula and western Kamchatka Peninsula) and southern (Hokkaido Island, Kuril Islands and Sakhalin Island) populations; (2) differences between the southern areas; (3) low variation among populations within some areas. The pattern contrasted strongly with that observed for Asian even‐broodline populations, which had a strong structure, possibly related to geographic and oceanographic influences. Isolation‐by‐distance analyses of each of the two broodlines showed a stronger relationship (x 4·8) among even‐ than odd‐broodline populations. Allele frequency differences between even‐ and odd‐broodlines reflected the reproductive isolation of the broodlines. However, there were no fixed frequency differences which, considered with the differing population structures, suggests that migration‐drift equilibrium has not yet obtained in one or both broodlines. The structural differences also suggest it is likely that the even‐ and odd‐broodlines are of different ages and that one is derived from the other. Allozyme data do not provide a genealogical basis for identifying the ancestral lineage.

The first catches of Atlantic salmon, Salmo salar L., in British Columbia (BC) waters occurred in 1987. The first reported escape of Atlantic salmon (2000 individuals) occurred in 1988. From 1988 to 1995, 97 799 Atlantic salmon were reported escaped from net pens in BC but the true number was higher as not all escapes are reported. Since 1987 a total of 9096 Atlantic salmon was caught in the coastal marine waters of BC, Washington and Alaska, and 188 were caught in fresh water. Most catches occurred in the Johnstone Strait area, where the abundance of salmon farms is highest. The most distant recovery occurred in 1994 when an Atlantic salmon was caught near the western end of the Alaska Peninsula. There have been no reports of successful reproduction of Atlantic salmon in the wild and no feral juveniles have been found. Atlantic salmon caught in the ocean in BC have substantial amounts of adipose tissue and they are heavier at length than fish caught in Alaska. The proportion of fish with prey items in their stomachs is generally low but higher in Alaska (13.1%) than in BC (5.8%). Most fish caught in fresh water are either maturing or mature.

An immature female Atlantic salmon Salmo salar, caught by a commercial salmon troller off southeastern Alaska on 20 July 1990, is the first documented representative of this species in the marine waters of Alaska. Identification was based on morphology, meristic characters, and protein electrophoresis. Scale growth patterns, an eroded or clipped dorsal fin, and a high proportion of regenerated scales indicate that the fish escaped from an aquaculture pen during spring 1990. Five additional Atlantic salmon were subsequently caught by commercial fishermen in southeastern Alaska during August 1991; identification was based on morphology and color patterns, Escaped Atlantic salmon are unlikely to have a genetic impact on native Pacific salmonids, but the possibility exists that they will disseminate nonendemic pathogens or parasites.