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We genotyped Chinook salmon (Oncorhynchus tshawytscha) from the Bering Sea and North Pacific Ocean for 43 single-nucleotide polymorphisms (SNPs) to investigate seasonal distribution and migration patterns. We analyzed 3563 immature fish from 22 spatiotemporal strata; composition analyses were performed using genotype data from spawning stocks spanning the species range. Substantial variation in stock composition existed among spatial and seasonal strata. We inferred patterns of seasonal migration based upon these data along with data from previous tag, scale, and parasite studies. We found that stocks from western Alaska and Yukon River overwinter on the Alaska continental shelf then travel to the middle and western Bering Sea during spring-fall. Stocks from California to Southeast Alaska were distributed in Gulf of Alaska year-round, with a substantial portion of this group migrating northward to the eastern Bering Sea during spring-fall. Proportions of Russian stocks increase when moving east to west in both the Bering Sea and North Pacific Ocean. These data can be used to better understand the impacts of fisheries and climate change on this valuable resource. Nous avons realise le genotypage de saumons quinnat (Oncorhynchus tshawytscha) de la mer de Bering et du Pacifique Nord pour 43 sites de polymorphisme mononucleotidique (SNPs) afin d'etudier la repartition saisonniere et les habitudes migratoires de ces saumons. Nous avons analyse 3563 poisons immatures issus de 22 strates spatiotemporelles; des analyses de la composition ont ete realisees a partir de donnees de genotypage pour des stocks reproducteurs recoupant toute l'aire de repartition de l'espece. Des variations importantes sur le plan de la composition des stocks des differentes strates spatiales et saisonnieres ont ete observees. Nous avons infere les habitudes de migration saisonnieres a la lumiere de ces donnees, ainsi que de donnees issues d'etudes de marquage, a l'echelle et de parasites. Nous avons constate que les stocks de l'ouest de l'Alaska et du fleuve Yukon passent l'hiver sur la plate-forme continentale de l'Alaska pour ensuite se diriger vers le milieu et l'ouest de la mer de Bering du printemps a l'automne. Des stocks provenant de la Californie au sud-est de l'Alaska sont presents dans le golfe d'Alaska a l'annee longue, une portion importante de ce groupe migrant vers le nord jusque dans la partie orientale de la mer de Bering, du printemps a l'automne. La proportion de stocks russes augmente d'est en ouest dans la mer de Bering et le Pacifique Nord. Ces donnees peuvent servir a etablir une meilleure comprehension des impacts de la peche et des changements climatiques sur cette ressource de grande valeur. [Traduit par la Redaction], Introduction Knowledge of the dynamics of migration and harvest of marine organisms is necessary to enable adequate conservation and management (Ruggerone and Goetz 2004; Welch et al. 2011). This critical [...]

Genetic data from nine species of the fish Merluccius, or hake, of America and Euro-Africa from 21 informative allozyme loci and new insight into phylogenetic and biogeographical relationships in the genus are discussed. A northwest Atlantic origin of the genus is likely, and likely unsampled M. albidus broadly distributed in the Caribbean is the most primitive species extant.

Colonization of brown trout in the postglacial period has been studied through distribution of allozyme variants in Europe. Fourteen published studies and unpublished data were used to compile data from 11 polymorphic allozyme loci. Three preglacial lineages existed, each fixed for different sets of alleles at the two loci, LDH-C and CK-A1. At the time of glacial retreat, recolonization seems to have taken place mostly into adjacent areas. A northern expansion from an Atlantic drainages refuge may have taken place in southern France and Iberia, and perhaps there was a northern/eastern radiation from a refuge near the English Channel and a north-western migration from an eastern Mediterranean-Caspian area refuge.

In allozyme analysis of tissue samples of 910 European hake, Merluccius merluccius, polymorphism was found at 21 of 34 protein-coding loci. The samples were from six North Atlantic and four Mediterranean locations. A major subdivision was seen from allelic differences related to the two collections. Gene flow from nearby Atlantic to proximal Mediterranean populations was suggested by allele frequencies and relevant oceanographic and geological information. Present management, based on two distinct populations, is justified. The differing and separate northern and southern stocks suggested by the International Council for the Exploration of the Sea (ICES) do not constitute an adequate description.

Since it was first described as a biological species by Jordan and Gilbert in 1880, has been a disputed taxonomic unit, generally regarded in recent decades as an intergeneric hybrid between English sole and starry flounder , both of which are common in coastal waters of the eastern North Pacific. Here, we investigate this suspected hybridization with molecular genetic and morphological data. Genotyping at four diagnostic allozyme loci clearly demonstrates that is an intergeneric hybrid between English sole and starry flounder; one individual was homozygous at one locus and may have been a backcross with starry flounder. Diagnostic restriction fragment length polymorphisms of a 464-base-pair region of the cytochrome b gene revealed symmetric, two-way directionality of hybridization in which 50% of maternities are assigned to each of the parental species. Principal components analysis of meristic characters demonstrated that is an intermediate between the parental species. Based on the low frequency of hybrids and the rarity of backcrosses, these natural hybridization events do not appear to be ecologically or evolutionarily significant. [ABSTRACT FROM AUTHOR]

This publication focuses on fisheries in the U.S. This January 2007 issue of "Fisheries" features various reports related to fishes, which include one about the role of fish biologists in ecological sustainability, another on fisheries management and another on the creation of the "Marine and Coastal Fisheries Journal." It details activities of the American Fisheries Society.