American Shad captured in the Penobscot river n the U.S. state of Maine. (Credit: Joe Zydlewski)
David Kazyak, Ph.D.
Dave Kazyak is a Supervisory Research Fish Biologist at the USGS Eastern Ecological Science Center in Kearneysville, WV.
Dave Kazyak is a Supervisory Research Fish Biologist at the USGS Eastern Ecological Science Center leads a conservation genetics and genomics research team. His research applies quantitative approaches in conservation genetics and population dynamics to provide decision-relevant information for imperiled species. Dave Kazyak's current projects use cutting-edge genetics tools to identify biologically-appropriate management units, measure rates of gene flow, and characterize how isolation, genetic drift, and hatchery supplementation impact wild populations. He also is working to develop novel approaches to census imperiled fishes, including techniques using combinations of acoustic telemetry, side-scan sonar, and genetics.
Professional Experience
2017-Present. U.S. Geological Survey, Eastern Ecological Science Center. Research Fish Biologist.
2015-2017. U.S. Geological Survey, Leetown Science Center (Integrated Statistics Contractor) - Postdoctoral Scientist.
Education and Certifications
Ph.D. 2015. University of Maryland (Marine Estuarine and Environmental Science)
M.S. 2011. University of Maine (Wildlife Ecology)
B.S. 2008. Frostburg State University (Wildlife and Fisheries)
Affiliations and Memberships*
American Fisheries Society
North American Sturgeon and Paddlefish Society
Science and Products
Sturgeon Occurrence and Behavior in the Outer Continental Shelf
Conservation Genetics of Atlantic Sturgeon
Alosine Genetic Stock Identification and Tissue Repository
Individual assignments and microsatellite genotypes for Atlantic Sturgeon from 2021 (ver. 2.0, February 2024)
Population genetic data for three at-risk tiger beetles Habroscelimorpha dorsalis dorsalis, H. d. media, and Ellipsoptera puritana
Population genetic data for flathead catfish from the Susquehanna and Delaware River basins in Pennsylvania and Maryland, USA
Population genetic data for wild Brook Trout (Salvelinus fontinalis) from the Midwestern United States and selected domestic strains
Genotypes of Atlantic Sturgeon collected from Canada to Georgia used in the development of a genetic baseline
Population genetics metrics for wild brook trout populations in North Carolina (1998-2016)
American Shad captured in the Penobscot river n the U.S. state of Maine. (Credit: Joe Zydlewski)
Integrating genetic and demographic data to refine indices of abundance for Atlantic sturgeon in the Hudson River, New York
Validation of a molecular sex marker in three sturgeons from eastern North America
Genetic population assignments of Atlantic sturgeon provided to National Marine Fisheries Service, 2022
A new genomic resource to enable standardized surveys of SNPs across the native range of brook trout (Salvelinus fontinalis)
Is now the time? Review of genetic rescue as a conservation tool for brook trout
U.S. Geological Survey invasive carp strategic framework, 2023–27
Utilization of genetic data to inform native Brook Trout conservation in North Carolina
Decades of global sturgeon conservation efforts are threatened by an expanding captive culture industry
Conservation genetics and wild trout: Evolving opportunities to support management
Benefits of genetic data for the design of Brook Trout translocation efforts
Multispecies approaches to status assessments in support of endangered species classifications
Evaluating sources of bias in pedigree-based estimates of breeding population size
Non-USGS Publications**
Management 36:259-266
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
Science and Products
- Science
Sturgeon Occurrence and Behavior in the Outer Continental Shelf
A new study aims to collect information on sturgeon temporal and spatial distribution to inform offshore wind energy and sand leasing operations.Conservation Genetics of Atlantic Sturgeon
Atlantic sturgeon genetic assignment testing assigns individuals to populations and is combined with life history data to present a comprehensive view of the species.Alosine Genetic Stock Identification and Tissue Repository
American Shad ( Alosa sapidissima ), Blueback Herring ( Alosa aestivalis ), and Alewife ( Alosa pseudoharengus ; collectively “alosines”) once supported large fisheries along the U.S. Atlantic Coast. However, impassable migration barriers, declines in habitat quality, and exploitation have led to declines in many spawning populations. Substantial resources have been invested to support the... - Data
Individual assignments and microsatellite genotypes for Atlantic Sturgeon from 2021 (ver. 2.0, February 2024)
This dataset includes genotypes and individual-based assignment tests for 868 Atlantic Sturgeon selected for assignment by the National Marine Fisheries Service to meet management requirements under the Endangered Species Act.Population genetic data for three at-risk tiger beetles Habroscelimorpha dorsalis dorsalis, H. d. media, and Ellipsoptera puritana
This dataset includes microsatellite genotypes for 16 collections of tiger beetles (Ellipsoptera puritana) distributed in Connecticut and Maryland, United States and 44 collections of Habroscelimorpha dorsalis dorsalis and 14 collections of H. d. media distributed from Massachusetts to Florida, United States.Population genetic data for flathead catfish from the Susquehanna and Delaware River basins in Pennsylvania and Maryland, USA
This dataset includes microsatellite genotypes for 137 flathead catfish from the Susquehanna River and Delaware River basins in Pennslyvania and Maryland, USA. Each individual was genotyped at 13 loci. Additional information about sex, capture date, and size are also provided for most individuals.Population genetic data for wild Brook Trout (Salvelinus fontinalis) from the Midwestern United States and selected domestic strains
This dataset includes microsatellite genotypes for 8,454 brook trout from 188 wild Midwestern populations and 26 hatchery strains of both Midwest and eastern (Atlantic seaboard) origin. Each individual was genotyped at either 5 or 7 loci.Genotypes of Atlantic Sturgeon collected from Canada to Georgia used in the development of a genetic baseline
This dataset includes microsatellite genotypes for 2510 Atlantic sturgeon from 18 different populations distributed from Canada to Georgia. Each individual was genotyped at 12 loci. Additional information about sex, capture date, and size are also provided.Population genetics metrics for wild brook trout populations in North Carolina (1998-2016)
This data set includes information on 406 wild brook trout populations from across the State of North Carolina. Key genetics metrics on diversity and the extent of hatchery introgression are presented. These data accompany the following article: Kazyak, D.C., Rash, Jacob, Lubinski, B.A., and King, T.L., 2018, Assessing the impact of stocking northern-origin hatchery brook trout on the genetics - Multimedia
American Shad capture in the Penobscot river (Credit: Joe Zydlewski)American Shad capture in the Penobscot river (Credit: Joe Zydlewski)
American Shad captured in the Penobscot river n the U.S. state of Maine. (Credit: Joe Zydlewski)
American Shad captured in the Penobscot river n the U.S. state of Maine. (Credit: Joe Zydlewski)
- Publications
Filter Total Items: 36
Integrating genetic and demographic data to refine indices of abundance for Atlantic sturgeon in the Hudson River, New York
Critical to Atlantic sturgeon Acipenser oxyrinchus oxyrinchus recovery and monitoring is the ability to estimate abundance and identify age- and stock-specific threats to survival. As adult Atlantic sturgeon spend much of their lives broadly distributed in marine and estuarine environments, it is challenging to collect data needed to estimate these demographic parameters in the adult population. AAuthorsShannon L. White, Richard M. Pendleton, Amanda Higgs, Barbara A. Lubinski, Robin L. Johnson, David C. KazyakValidation of a molecular sex marker in three sturgeons from eastern North America
Despite the importance of sex-specific information for sturgeon conservation and management, sex identification has been a major challenge outside of mature adults on spawning grounds. Recent work identified a sex-specific locus (AllWSex2) that appears to be broadly conserved across many Acipenserids, but the assay was not validated for all species within the family. We tested the AllWSex2 markerAuthorsNicholas M Sard, Brian R Krieser, Richard M. Pendleton, Barbara A. Lubinski, Robin L. Johnson, Dewayne A. Fox, Joel P Van Eenennaam, Jason E Kahn, Chris H Hager, Amanda L. Higgs, David C. KazyakGenetic population assignments of Atlantic sturgeon provided to National Marine Fisheries Service, 2022
Acipenser oxyrinchus oxyrinchus (Atlantic sturgeon) were once abundant and supported large-scale fisheries throughout much of the east coast of the United States. However, historic overharvest and habitat loss resulted in dramatic declines in abundance and eventual listing under the Endangered Species Act of the United States. As part of this listing, Atlantic sturgeon populations were divided intAuthorsShannon L. White, Robin L. Johnson, Barbara A. Lubinski, Michael S. Eackles, David C. KazyakA new genomic resource to enable standardized surveys of SNPs across the native range of brook trout (Salvelinus fontinalis)
Understanding how genetic diversity is distributed across spatiotemporal scales in species of conservation or management concern is critical for identifying large-scale mechanisms affecting local conservation status and implementing large-scale biodiversity monitoring programmes. However, cross-scale surveys of genetic diversity are often impractical within single studies, and combining datasets tAuthorsNadya Mamoozadeh, Andrew R. Whiteley, Benjamin Letcher, David C. Kazyak, Charlene Tarsa, Mariah H. MeekIs now the time? Review of genetic rescue as a conservation tool for brook trout
Brook trout populations have been declining throughout their native range in the east coast of the United States. Many populations are now distributed in small, isolated habitat patches where low genetic diversity and high rates of inbreeding reduce contemporary viability and long-term adaptive potential. Although human-assisted gene flow could theoretically improve conservation outcomes through gAuthorsShannon L. White, Jacob M Rash, David C. KazyakU.S. Geological Survey invasive carp strategic framework, 2023–27
U.S. Geological Survey (USGS) research has supported management of Hypophthalmichthys nobilis (bighead carp), Mylopharyngodon piceus (black carp), Ctenopharyngodon idella (grass carp), and H. molitrix (silver carp), hereafter referred to collectively as invasive carps, for over a decade. This strategic framework identifies thematic research areas to guide funding decisions for USGS invasive carp rAuthorsDuane Chapman, Jon Amberg, Robin Calfee, Enrika Hlavacek, Jon Hortness, P. Ryan Jackson, David C. Kazyak, Brent Knights, James RobertsUtilization of genetic data to inform native Brook Trout conservation in North Carolina
As North Carolina’s only native salmonid, Brook Trout Salvelinus fontinalis is a fish of considerable ecological and cultural significance in the state, but anthropogenic alterations to the landscape and introductions of nonnative salmonids have fragmented and reduced its native range. As a result, the North Carolina Wildlife Resources Commission (NCWRC) has enacted numerous efforts to help conserAuthorsJacob Rash, David C. Kazyak, Shannon L. White, Barbara A. LubinskiDecades of global sturgeon conservation efforts are threatened by an expanding captive culture industry
After centuries of overexploitation and habitat loss, many of the world's sturgeon (Acipenseridae) populations are at the brink of extinction. Although significant resources are invested into the conservation and restoration of imperiled sturgeons, the burgeoning commercial culture industry poses an imminent threat to the persistence of many populations. In the past decade, the number and distribuAuthorsShannon L. White, Dewayne A. Fox, Tamar Beridze, Stephania K Bolden, Robin L. Johnson, Thomas F Savoy, Fleur Scheele, Andrea D Schreier, David C. KazyakConservation genetics and wild trout: Evolving opportunities to support management
It is increasingly apparent that our planet is undergoing rapid, unprecedented environmental change. These changes are already impacting wild trout populations, leading to declines in occupancy and abundance across increasingly fragmented landscapes. Many changes are projected to intensify in the coming decades, which are likely to be crucial to the future of many wild populations. While there isAuthorsDavid C. Kazyak, Shannon L. White, N. Mamoozadeh, John Hargrove, Mariah MeekBenefits of genetic data for the design of Brook Trout translocation efforts
With wild trout populations in decline, many conservation practitioners are evaluating the feasibility of incorporating reintroduction and genetic rescue into management frameworks. As interest in these conservation tools continues to grow, so too has the need for rigorous science to evaluate translocation success and improve the efficacy of future efforts. From this, it has become increasingly apAuthorsShannon L. White, Thomas C Johnson, Jacob M Rash, Barbara A. Lubinski, David C. KazyakMultispecies approaches to status assessments in support of endangered species classifications
Multispecies risk assessments have developed within many international conservation programs, reflecting a widespread need for efficiency. Under the United States Endangered Species Act (ESA), multispecies assessments ultimately lead to species-level listing decisions. Although this approach provides opportunities for improved efficiency, it also risks overwhelming or biasing the assessment procesAuthorsDaniel Bruce Fitzgerald, Mary Freeman, Kelly O. Maloney, John A. Young, Amanda E. Rosenberger, David C. Kazyak, David R. SmithEvaluating sources of bias in pedigree-based estimates of breeding population size
Applications of genetic-based estimates of population size are expanding, especially for species for which traditional demographic estimation methods are intractable due to the rarity of adult encounters. Estimates of breeding population size (NS) are particularly amenable to genetic-based approaches as the parameter can be estimated using pedigrees reconstructed from genetic data gathered from diAuthorsShannon L. White, Nicholas M Sard, Harold M Brundage III, Robin L. Johnson, Barbara A. Lubinski, Michael S. Eackles, Ian A Park, Dewayne A. Fox, David C. KazyakNon-USGS Publications**
Hilderbrand RH, Kazyak DC. 2017. Spatiotemporal patterns of Brook Trout abundance and implications for stream monitoring. North American Journal of Fisheries Management 37:353-362.Kazyak DC, Hilderbrand RH, King TL, Keller SR, Chhatre VE. 2016. Hiding in plain sight: a case for cryptic metapopulations in Brook Trout (Salvelinus fontinalis). PLOS ONE 11(1): e0146295. doi:10.1371/journal.pone.0146295Kazyak DC, Sell MT, Cooper R, Hilderbrand RH. 2016. A comparison of catchability and mortality with circle and J hooks for stream-dwelling Brook Trout Salvelinus fontinalis. North American Journal of Fisheries
Management 36:259-266
Sell MT, Kazyak DC, Hilderbrand RH, Heft AA, Cooper RM. 2016. A comparison of circle hook size on hooking success, deep hooking rate, and post release mortality of hatchery-reared Rainbow Trout Oncorhynchus mykiss. North American Journal of Fisheries Management 36:254-258
Kazyak DC, Hilderbrand RH, Keller SK, Colaw M, Holloway AE, Morgan RP, King TL. 2015. Spatial structure of morphological and neutral genetic variation in Brook Trout Salvelinus fontinalis. Transactions of the American Fisheries Society 144:480-490Kazyak DC, Hilderbrand RH, Sell MT. 2014. Growth variation in a Mid-Atlantic Brook Trout population. Proceedings of Wild Trout XI. Supplement:350-356
Sell MT, Heft AA, Kazyak DC, Hilderbrand RH, Morgan RP. 2014. Short-term and seasonal movements of eastern Brook Trout (Salvelinus fontinalis) in the upper Savage River watershed, Garrett County, Maryland. Proceedings of Wild Trout XI. Supplement:357-362Stranko SA, Ashton MJ, Hilderbrand RH, Weglein SL, Kazyak DC, Kilian JV. 2014. Fish and benthic macroinvertebrate densities in small streams with and without American Eels. Transactions of the American Fisheries Society 143:700-708Kazyak DC, Letcher BH, Zydlewski J, O'Donnell MJ. 2013. Growth variability of brook charr (Salvelinus fontinalis) in coastal Maine. Ecology of Freshwater Fish. doi: 10.1111/eff.12105
Kazyak DC, Hilderbrand RH, Holloway AE. 2013. Rapid visual assessment to determine sex in Brook Trout. North American Journal of Fisheries Management 33:665-668Kazyak DC, Zydlewski J. 2012. High-density polyethylene: a new material for pass-over PIT antennas. North American Journal of Fisheries Management 32:49-52Strain, GF, Kazyak DC. Raesly R. 2012. Headwaters and headlamps: a comparison of nocturnal and diurnal surveys to estimate richness, abundance, and detection of streamside salamanders. Herpetological Review 43:26-30**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
- News
*Disclaimer: Listing outside positions with professional scientific organizations on this Staff Profile are for informational purposes only and do not constitute an endorsement of those professional scientific organizations or their activities by the USGS, Department of the Interior, or U.S. Government