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Populations of several billfish species are declining due to overfishing and bycatch, and fundamental aspects of their biology and population dynamics remain poorly understood. We provide the first assessment of the population genetic structure of longbill spearfish (Tetrapturus pfluegeri) in the western Atlantic Ocean. We screened variation at 12 nuclear microsatellite loci (n = 144) and mitochondrial DNA control region seque...
Embryonic selfish‐herding blurs the line between brood parasitism and mutualism for communal‐breeding stream fishesNARA Subscribed
Mutualisms are complex, interspecific relationships, which sometimes create “selfish‐herds” as individuals of each species compete to maximize their own fitness. Nest association , where individuals of different species spawn on a nest created by a host species, is a reproductive interaction characteristic of some minnows (Leuciscidae) and is considered mutualistic despite mimicking the behavior labeled “brood parasitism.” We...
Walleye Sander vitreus is a valued sportfish in eastern North America, including the upper New River of Virginia, where individuals can grow to a large size (>7 kg). After construction of dams, especially Claytor Dam in 1939, the population declined and non-native walleye were stocked. Stocking of non-native walleye was stopped in 1997, and molecular marker data showed that the presumptive native population had persisted. To r...
Fish growth is a fundamental biological process driven by a multitude of intrinsic (within-individual) and extrinsic (environmental) factors that underpin individual fitness and population dynamics. Interannual variability in river hydrology regarding the intensity and duration of floods and droughts can induce interannual variations in the biotic and abiotic variables that regulate fish growth. However, the understanding of h...
Walleye is an important sportfish across eastern North America, is commercially fished in the Laurentian Great Lakes region, and has been introduced outside its native range. Thirty-eight Walleye populations within six watersheds across the Eastern Highlands and other portions of the native range were screened at eight microsatellite DNA loci to better understand evolutionary history and to inform fishery management and conser...
Candy darter Etheostoma osburni, a federally endangered non-game fish, has been extirpated from most of its historic range in Virginia and now occurs in four isolated populations in the New River drainage. Understanding of population genetic structure will provide insights into the recent natural history of the species and can inform conservation management. Our objectives were to: characterize population genetic structure, es...
Clinch Dace (Chrosomus sp. cf. saylori) is a newly recognized and yet-undescribed species of minnow with a restricted and fragmented distribution in the upper Tennessee River basin in southwestern Virginia, USA. We collected Clinch Dace from seven streams and observed variations at nine selectively neutral microsatellite DNA loci to infer population genetic processes and identify units for conservation management. Bayesian clu...
A Synthesis of the Ecology and Conservation of Pseudoplatystoma Catfishes in the NeotropicsOA Marine
Species of the genus Pseudoplatystoma, the long-whiskered catfishes, are important in commercial and recreational fisheries in South America, and some species have become key to regional aquaculture. Some species of the genus are under pressure due to overfishing and the negative impacts of dams. Six questions are asked in this review: (i) What species are in the genus, and where are they distributed? (ii) What are the life hi...
Genetics and biotechnology make increasingly important contributions to fishery science, fishery management, aquaculture, and related fields [...]
Advances in fisheries and aquaculture science often follow the introduction of new tools or analytic methods [...]
Towards progressive regulatory approaches for agricultural applications of animal biotechnologyNARA Subscribed
Traditional breeding techniques, applied incrementally over thousands of years, have yielded huge benefits in the characteristics of agricultural animals. This is a result of significant, measurable changes to the genomes of those animal species and breeds. Genome editing techniques may now be applied to achieve targeted DNA sequence alterations, with the potential to affect traits of interest to production of agricultural ani...
The farming and husbandry of Colossoma macropomum : From Amazonian waters to sustainable productionNARA Subscribed
Within the rich diversity of South American freshwater fish, Colossoma macropomum (Characiformes: Serrasalmidae), known as tambaqui, cachama or blackfin pacu, can reach 30 kg, is a traditional product in regional fish markets and has drawn the attention of fish farmers since the 1930s. Considerable progress achieved in different fields of aquaculture science has contributed to the growth of tambaqui production. Tambaqui has pr...
Direct and indirect measures of individual movement provide valuable knowledge regarding a species’ resiliency to environmental change. Information on patterns of movement can inform species management and conservation but is lacking for many imperiled fishes. The Candy Darter, Etheostoma osburni, is an endangered stream fish with a dramatically reduced distribution in Virginia in the eastern United States, now known from only...
Testing a global standard for quantifying species recovery and assessing conservation impactNARA Subscribed
Recognizing the imperative to evaluate species recovery and conservation impact, in 2012 the International Union for Conservation of Nature (IUCN) called for development of a “Green List of Species” (now the IUCN Green Status of Species). A draft Green Status framework for assessing species’ progress toward recovery, published in 2018, proposed 2 separate but interlinked components: a standardized method (i.e., measurement aga...
“A new journey for Fishes” [...]