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  1. Article ; Online: Pool Age and Local Habitat Are Associated with Effective Number of Breeders in Spotted Salamander Populations Colonizing Created Vernal Pools

    Millikin, Alice R. / Coster, Stephanie S. / Welsh, Amy B. / Anderson, James T.

    Diversity. 2023 Jan. 17, v. 15, no. 2

    2023  

    Abstract: Population genetics can reveal whether colonization of created habitats has been successful and inform future strategies for habitat creation. We used genetic analysis to investigate spotted salamander (Ambystoma maculatum) colonization of created vernal ...

    Abstract Population genetics can reveal whether colonization of created habitats has been successful and inform future strategies for habitat creation. We used genetic analysis to investigate spotted salamander (Ambystoma maculatum) colonization of created vernal pools and explored the impact of habitat characteristics on the genetic diversity and connectivity of the pools. Our first objective was to examine genetic structure, differentiation, diversity, and potential for a founder effect. Our second objective was to determine if habitat characteristics were associated with effective number of breeders, relatedness, or genetic diversity. We sampled spotted salamander larvae in 31 created vernal pools (1–5 years old) in Monongahela National Forest (WV) in May and June 2015 and 2016. The youngest pools exhibited genetic differentiation, a founder effect, and low effective number of breeders. Effective number of breeders was positively associated with pool age, vegetation cover, pool diameter, and sample size. Vegetation cover was also negatively associated with relatedness. Genetic diversity did not have strong environmental predictors. Our results indicated the effective number of breeders increased and genetic differentiation decreased within 4–5 years of pool creation, a sign of rapid colonization and potential population establishment. Our research also showed that higher vegetative cover within the pool and larger pool diameters could impact habitat quality and should be incorporated into future pool creation.
    Keywords Ambystoma ; founder effect ; genetic analysis ; genetic structure ; genetic variation ; habitats ; salamanders and newts ; sample size ; vegetation cover ; Monongahela National Forest
    Language English
    Dates of publication 2023-0117
    Publishing place Multidisciplinary Digital Publishing Institute
    Document type Article ; Online
    ZDB-ID 2518137-3
    ISSN 1424-2818
    ISSN 1424-2818
    DOI 10.3390/d15020124
    Database NAL-Catalogue (AGRICOLA)

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  2. Article: Novel hair snare and genetic methods for non-invasive bobcat detection.

    Rounsville, Thomas F / Rogers, Richard E / Welsh, Amy B / Ryan, Christopher W / Anderson, James T

    Ecology and evolution

    2022  Volume 12, Issue 1, Page(s) e8435

    Abstract: Over the past 20 years, the use of non-invasive hair snare surveys in wildlife research and management has become more prevalent. While these tools have been used to answer important research questions, these techniques often fail to gather information ... ...

    Abstract Over the past 20 years, the use of non-invasive hair snare surveys in wildlife research and management has become more prevalent. While these tools have been used to answer important research questions, these techniques often fail to gather information on elusive carnivores, such as bobcats (
    Language English
    Publishing date 2022-01-24
    Publishing country England
    Document type Journal Article
    ZDB-ID 2635675-2
    ISSN 2045-7758
    ISSN 2045-7758
    DOI 10.1002/ece3.8435
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article: Genetic Considerations in the Restoration of Small Forest Populations: Perspectives From Fish and Wildlife Genetics

    Welsh, Amy B

    Journal of sustainable forestry. 2014 May 30, v. 33, no. sup1

    2014  

    Abstract: The evolutionary forces that drive recent population genetic changes include migration, mating strategy, genetic drift, and selection. However, the strength of these forces varies depending on population size. The purpose of this article is to review ... ...

    Abstract The evolutionary forces that drive recent population genetic changes include migration, mating strategy, genetic drift, and selection. However, the strength of these forces varies depending on population size. The purpose of this article is to review genetic issues associated with small forest populations and to provide perspectives from fish and wildlife genetics through case studies. Small populations are often fragmented, potentially preventing migration. In forest trees, long-distance pollen dispersal and highly mobile, generalist pollinators can help maintain connectivity. A landscape and community approach to understanding connectivity is critical (case study: mussels). Outbreeding depression can also be a concern in forest restoration. This becomes a greater risk when mixing populations that are highly diverged and when the species is polyploid. Management units should be designated that mimic natural gene flow (case study: lake sturgeon). At the other extreme, inbreeding depression can result in reduced fitness. When inbreeding depression is a concern, genetic rescue may be necessary (case study: Florida panther). Loss of diversity through genetic drift can occur with small effective population sizes (N ₑ) and a small number of founders (case study: salmonids). Selection is most likely to occur through adaptation to captivity or introduction of resistant/tolerant strains (case study: amphibians).
    Keywords Acipenser fulvescens ; Puma concolor ; Salmonidae ; amphibians ; captive animals ; case studies ; fish ; forest restoration ; forest trees ; forests ; gene flow ; genetic drift ; genetic rescue ; inbreeding ; inbreeding depression ; landscapes ; mussels ; outbreeding depression ; pollen flow ; pollinators ; polyploidy ; population size ; risk ; sustainable forestry ; wildlife
    Language English
    Dates of publication 2014-0530
    Size p. S66-S92.
    Publishing place Taylor & Francis
    Document type Article
    ZDB-ID 2094282-5
    ISSN 1540-756X ; 1054-9811
    ISSN (online) 1540-756X
    ISSN 1054-9811
    DOI 10.1080/10549811.2014.887475
    Database NAL-Catalogue (AGRICOLA)

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  4. Article: Tracking Stocking Success in a Long‐Lived Species through Genetics and Demographics: Evidence of Natural Reproduction in Lake Sturgeon after Twenty‐Two Years

    Welsh, Amy B. / Carlson, Douglas M. / Schlueter, Scott L. / Jackson, James R.

    Transactions of the American Fisheries Society. 2020 Jan., v. 149, no. 1

    2020  

    Abstract: Lake Sturgeon Acipenser fulvescens populations throughout the Great Lakes have experienced declines. Therefore, Lake Sturgeon have been stocked at several locations, including the Oswegatchie River in New York State, where Lake Sturgeon are listed as ... ...

    Abstract Lake Sturgeon Acipenser fulvescens populations throughout the Great Lakes have experienced declines. Therefore, Lake Sturgeon have been stocked at several locations, including the Oswegatchie River in New York State, where Lake Sturgeon are listed as threatened. The goal of New York's Lake Sturgeon stocking program has been the establishment of self‐sustaining populations in six out of the seven management units in order to meet delisting criteria. Due to Lake Sturgeon's long lifespan and late sexual maturity, there is a significant delay before it can be determined whether natural reproduction is occurring at the reintroduction site. Our objective was to determine whether recently captured Lake Sturgeon from the Oswegatchie River were of hatchery origin and whether natural reproduction was occurring in the river. Age data and genetic data from 12 microsatellite loci were collected from 38 individuals from the Oswegatchie River. The genetic data were used to reconstruct families by using COLONY and STRUCTURE statistical analysis programs. The genetic diversity of the Oswegatchie River population was also compared with other natural and introduced Lake Sturgeon populations in the region. The combination of family reconstruction and age data indicated that natural reproduction is occurring in the Oswegatchie River. Individuals that were presumed to be recruited had ages ranging from 6 to 12 years. It is often thought female Lake Sturgeon typically do not reach sexual maturity until about 20 years of age. Only 12–15 years had elapsed since the earliest times of stocking, suggesting the possibility that remnant native females remained in the system or stocked female Lake Sturgeon have reached early sexual maturity. The genetic diversity of the Lake Sturgeon population in the Oswegatchie River is comparable to that of other nearby natural populations. However, the effective population size (Nₑ) was lower than that of many natural populations. As natural reproduction continues in the Oswegatchie River, Nₑ will likely increase.
    Keywords Acipenser fulvescens ; demographic statistics ; effective population size ; females ; genetic variation ; hatcheries ; longevity ; microsatellite repeats ; reproduction ; rivers ; sexual maturity ; statistical analysis ; New York
    Language English
    Dates of publication 2020-01
    Size p. 121-130.
    Publishing place John Wiley & Sons, Ltd
    Document type Article
    Note JOURNAL ARTICLE
    ZDB-ID 416724-7
    ISSN 0002-8487
    ISSN 0002-8487
    DOI 10.1002/tafs.10214
    Database NAL-Catalogue (AGRICOLA)

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  5. Article: Watershed‐level brook trout genetic structuring: Evaluation and application of riverscape genetics models

    Nathan, Lucas R / Vokoun, Jason C / Welsh, Amy B

    Freshwater biology. 2019 Mar., v. 64, no. 3

    2019  

    Abstract: Stream connectivity promotes resilience and population viability of aquatic organisms. Landscape genetic approaches, traditionally applied to terrestrial systems, may reveal important watershed‐level dynamics that influence connectivity. Additional ... ...

    Abstract Stream connectivity promotes resilience and population viability of aquatic organisms. Landscape genetic approaches, traditionally applied to terrestrial systems, may reveal important watershed‐level dynamics that influence connectivity. Additional validation would improve understanding of how the models perform when gene flow is constrained to dendritic networks. The objectives of this study were to use simulations to assess the utility of landscape genetics analyses in dendritic stream networks and investigate riverscape variables influencing gene flow among brook trout Salvelinus fontinalis populations in headwater streams. We used an individual‐based simulation program to simulate different dispersal scenarios and used combinations of landscape genetic models, model selection methods, and genetic metrics to determine the best combination for riverscape systems. We also sampled brook trout from 76 headwater streams in two watersheds (c. 1,000 km2) in Connecticut, U.S.A. to assess connectivity and riverscape influences on genetic structuring. Gravity models with Bayesian information criterion (BIC) selection were the most accurate (>85%) landscape genetic models that consistently identified the correct simulated gene flow barrier. However, all models performed poorly when unidirectional barriers were simulated without a distance‐based dispersal limitation. Excluding this scenario, model accuracy for the gravity models using BIC selection was >90% across multiple genetic metrics, validating the application of landscape genetic models to riverscape systems. We found highly variable levels of brook trout genetic connectivity (FST range 0.01–0.19) at the watershed level (5–15 river km). Gravity models identified increases in upstream impervious surfaces and decreases in riparian tree canopy cover as riverscape variables associated with increases in genetic differentiation in one watershed, while the other watershed was consistent with an isolation by distance pattern. In this study we used demogenetic (i.e. combined demographic and genetic) simulations to demonstrate the utility of landscape genetics techniques in dendritic river networks. Our empirical genetic study documented gene flow among headwater populations of brook trout at the watershed level and also suggested connectivity can be limited by watershed development. Incorporating the heterogeneity of riverscapes into connectivity‐focused conservation planning is essential to the development of effective restoration actions, and landscape genetics approaches can be useful tools to identify watershed‐level connectivity in stream systems.
    Keywords aquatic organisms ; Bayesian theory ; canopy ; computer simulation ; gene flow ; genetic models ; genetic variation ; landscape genetics ; planning ; population viability ; rivers ; Salvelinus fontinalis ; selection methods ; streams ; trees ; water ; watersheds ; Connecticut
    Language English
    Dates of publication 2019-03
    Size p. 405-420.
    Publishing place John Wiley & Sons, Ltd
    Document type Article
    Note JOURNAL ARTICLE
    ZDB-ID 121180-8
    ISSN 0046-5070
    ISSN 0046-5070
    DOI 10.1111/fwb.13230
    Database NAL-Catalogue (AGRICOLA)

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  6. Article: Genetic swamping and possible species collapse: tracking introgression between the native Candy Darter and introduced Variegate Darter

    Gibson, Isaac / Cincotta, Daniel A / Welsh, Amy B / Welsh, Stuart A

    Conservation genetics. 2019 Apr., v. 20, no. 2

    2019  

    Abstract: Candy Darters (Etheostoma osburni) and Variegate Darters (E. variatum) are both native to West Virginia and Virginia. The geographic ranges of these two species were historically separated by Kanawha Falls, a natural barrier to fish dispersal located at ... ...

    Abstract Candy Darters (Etheostoma osburni) and Variegate Darters (E. variatum) are both native to West Virginia and Virginia. The geographic ranges of these two species were historically separated by Kanawha Falls, a natural barrier to fish dispersal located at Glen Ferris, WV. In the early 1980s, Variegate Darters or putative hybrids (E. osburni × E. variatum) were first collected at locations upstream of Kanawha Falls, and have since undergone range expansion. Hybridization with the Variegate Darter was one of the threats that led to the Candy Darter being listed as Endangered under the U.S. Endangered Species Act in 2018. Genetic and morphologic data were examined for individuals from the New, Gauley, and Greenbrier river drainages. Individuals were genotyped using a suite of 5 diagnostic microsatellite loci to investigate potential hybridization. Widespread hybridization was found throughout populations of Candy Darters, with the geographic range of hybridization expanding from 2004 to 2014. A hybrid zone was observed, with the highest levels of Variegate Darter introgression representing the kernel within this zone and the locations of first-generation (F1) hybrids at the periphery. F1 hybrids were morphologically intermediate within and across characters for parental species. Introgressive hybridization threatens the genetic integrity of the Candy Darter, and may lead to population extirpation or extinction.
    Keywords Endangered Species Act of 1973 ; Etheostoma osburni ; extinction ; fish ; genetic stability ; genotyping ; hybrids ; introgression ; microsatellite repeats ; rivers ; seeds ; Virginia ; West Virginia
    Language English
    Dates of publication 2019-04
    Size p. 287-298.
    Publishing place Springer Netherlands
    Document type Article
    ZDB-ID 2059560-8
    ISSN 1572-9737 ; 1566-0621
    ISSN (online) 1572-9737
    ISSN 1566-0621
    DOI 10.1007/s10592-018-1131-2
    Database NAL-Catalogue (AGRICOLA)

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  7. Article: Evaluation of Genetic Structuring within GIS‐Derived Brook Trout Management Units

    Nathan, Lucas R. / Kanno, Yoichiro / Letcher, Benjamin H. / Welsh, Amy B. / Whiteley, Andrew R. / Vokoun, Jason C.

    Transactions of the American Fisheries Society. 2020 Nov., v. 149, no. 6

    2020  

    Abstract: Delineation of management units across broad spatial scales can help to visualize population structuring and identify conservation opportunities. Geographical information system (GIS) approaches can be useful for developing broad‐scale management units, ... ...

    Abstract Delineation of management units across broad spatial scales can help to visualize population structuring and identify conservation opportunities. Geographical information system (GIS) approaches can be useful for developing broad‐scale management units, especially when paired with field data that can validate the GIS‐based delineations. Genetic data can be useful for evaluating whether management units accurately represent population structuring. The Eastern Brook Trout Joint Venture, a regionwide collaborative group, delineated patch‐based management units for Brook Trout Salvelinus fontinalis by using GIS approaches to inform conservation strategies across the eastern United States. The objectives of this research were to (1) evaluate how well the patches predicted Brook Trout genetic structuring in Connecticut, USA; (2) modify the patches as needed to represent contemporary genetic structuring; and (3) identify catchment‐ and patch‐scale riverscape characteristics that predict genetic diversity. Patches with dams and high levels of upstream impervious surfaces (>3%) had increased intrapatch genetic structuring, which we incorporated into our revised patch delineation algorithm. Patch area and catchment area were the best predictors of genetic diversity, suggesting the importance of maintaining connectivity and incorporating patch‐scale processes into conservation actions. The modified patch layer could be used as the basis for Brook Trout management units to help predict population structuring in the absence of watershed‐scale genetic data, allowing opportunities for Brook Trout conservation to be identified.
    Keywords Salvelinus fontinalis ; algorithms ; genetic variation ; geographic information systems ; rivers ; watersheds ; Connecticut
    Language English
    Dates of publication 2020-11
    Size p. 681-694.
    Publishing place John Wiley & Sons, Ltd
    Document type Article
    Note JOURNAL ARTICLE
    ZDB-ID 416724-7
    ISSN 0002-8487
    ISSN 0002-8487
    DOI 10.1002/tafs.10260
    Database NAL-Catalogue (AGRICOLA)

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  8. Article: Are culvert assessment scores an indicator of Brook Trout Salvelinus fontinalis population fragmentation?

    Nathan, Lucas R / Smith, Ava A / Vokoun, Jason C / Welsh, Amy B

    Ecological indicators. 2018 Jan., v. 84

    2018  

    Abstract: Fragmentation is a major threat to the integrity of stream ecosystems and maintaining connectivity is a primary goal for conservation to promote natural system functioning. In human dominated systems with extensive anthropogenic fragmentation, resource ... ...

    Abstract Fragmentation is a major threat to the integrity of stream ecosystems and maintaining connectivity is a primary goal for conservation to promote natural system functioning. In human dominated systems with extensive anthropogenic fragmentation, resource managers are faced with prioritizing restoration actions to provide the most cost-effective conservation strategies. Road crossings, particularly poorly designed culverts, limit fish passage and thus population connectivity and access to seasonally important resources. Culvert assessment protocols, such as the one developed by the North Atlantic Aquatic Connectivity Collaborative (NAACC), are useful tools for managers to evaluate culvert passability and prioritize restoration actions across broad spatial extents, however the justification of such protocols requires empirical field based investigations. In this study we collected Brook Trout genetic samples from 28 headwater streams, of which 17 were separated by a culverted road crossing and 11 were included as a comparison to natural genetic structuring. The objectives of this research were to 1) determine what effect culverts had on the genetics of Brook Trout populations, 2) evaluate the ability of the NAACC culvert assessment protocol to predict genetic patterns and 3) identify the culvert characteristics that best explained genetic variability. We found significant increases in genetic differentiation at sites with culverts compared to those without, but no differences in genetic diversity metrics. Although the NAACC classifications did not predict the extent of genetic differentiation, the openness ratio of culverts (cross sectional area/length) was significantly correlated, suggesting it may need to receive a higher weighting in assessment protocols. Our results highlight the necessity to match appropriate prioritization strategies with desired management objectives in order to design the most effective conservation actions.
    Keywords cost effectiveness ; culverts ; ecosystems ; fish ; genetic variation ; humans ; managers ; prioritization ; roads ; Salvelinus fontinalis ; streams
    Language English
    Dates of publication 2018-01
    Size p. 208-217.
    Publishing place Elsevier Ltd
    Document type Article
    ZDB-ID 2036774-0
    ISSN 1872-7034 ; 1470-160X
    ISSN (online) 1872-7034
    ISSN 1470-160X
    DOI 10.1016/j.ecolind.2017.08.033
    Database NAL-Catalogue (AGRICOLA)

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  9. Article: Genetic Assignment of Brook Trout Reveals Rapid Success of Culvert Restoration in Headwater Streams

    Wood, Darren M. / Welsh, Amy B. / Todd Petty, J.

    North American journal of fisheries management. 2018 Oct., v. 38, no. 5

    2018  

    Abstract: Fragmentation of aquatic habitats is a global conservation concern. Losses of both biodiversity and genetic diversity have been attributed to this phenomenon as dispersal movements between habitat patches are restricted. Brook Trout Salvelinus fontinalis ...

    Abstract Fragmentation of aquatic habitats is a global conservation concern. Losses of both biodiversity and genetic diversity have been attributed to this phenomenon as dispersal movements between habitat patches are restricted. Brook Trout Salvelinus fontinalis in the upper Shavers Fork watershed of West Virginia exhibit high dispersal rates and lengthy dispersal distances; however, road culverts have been hypothesized to influence the movement of Brook Trout between tributaries. Removing impassable culverts could serve as a tool to facilitate movements into previously isolated streams. We classified the passability of road culverts by their physical attributes and collected samples above each structure as well as in two streams without culverts to test for genetic population differentiation attributed to culverts. After we determined that the majority of streams consisted of a single genetic population, with the exception of two streams containing culverts designated as impassable (Beaver Creek and Lamothe Hollow), the culvert structures were restored to eliminate outlets perched above the stream bottom and were subsequently resampled 1 year after project completion. Although no individuals were assigned as first‐generation migrants into either Beaver Creek or Lamothe Hollow before culvert restoration, five individuals were detected as first‐generation migrants into Beaver Creek (13%), and one individual was identified as a first‐generation migrant into Lamothe Hollow (4.5%) after culvert restoration. Three different streams were found to be sources of the migrants into Beaver Creek, and the single individual migrating into Lamothe Hollow was from a fourth source stream. The identification of first‐generation migrants through genetic assignment not only provides a tool with which to test the effectiveness of barrier removal and subsequent restoration success but also to support the importance of culvert replacement in headwater streams.
    Keywords Salvelinus fontinalis ; administrative management ; biodiversity ; culverts ; genetic variation ; streams ; water ; watersheds ; West Virginia
    Language English
    Dates of publication 2018-10
    Size p. 991-1003.
    Publishing place John Wiley & Sons, Ltd
    Document type Article
    Note JOURNAL ARTICLE
    ZDB-ID 779391-1
    ISSN 0275-5947
    ISSN 0275-5947
    DOI 10.1002/nafm.10185
    Database NAL-Catalogue (AGRICOLA)

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  10. Article: Genetic effects of habitat restoration in the Laurentian Great Lakes: an assessment of lake sturgeon origin and genetic diversity

    Marranca, Jamie M / Welsh, Amy B / Roseman, Edward

    Restoration ecology. 2015 July, v. 23, no. 4

    2015  

    Abstract: Lake sturgeon (Acipenser fulvescens) have experienced significant habitat loss, resulting in reduced population sizes. Three artificial reefs were built in the Huron‐Erie corridor in the Great Lakes to replace lost spawning habitat. Genetic data were ... ...

    Abstract Lake sturgeon (Acipenser fulvescens) have experienced significant habitat loss, resulting in reduced population sizes. Three artificial reefs were built in the Huron‐Erie corridor in the Great Lakes to replace lost spawning habitat. Genetic data were collected to determine the source and numbers of adult lake sturgeon spawning on the reefs and to determine if the founder effect resulted in reduced genetic diversity. DNA was extracted from larval tail clips and 12 microsatellite loci were amplified. Larval genotypes were then compared to 22 previously studied spawning lake sturgeon populations in the Great Lakes to determine the source of the parental population. The effective number of breeders (Nb) was calculated for each reef cohort. The larval genotypes were then compared to the source population to determine if there were any losses in genetic diversity that are indicative of the founder effect. The St. Clair and Detroit River adult populations were found to be the source parental population for the larvae collected on all three artificial reefs. There were large numbers of contributing adults relative to the number of sampled larvae. There was no significant difference between levels of genetic diversity in the source population and larval samples from the artificial reefs; however, there is some evidence for a genetic bottleneck in the reef populations likely due to the founder effect. Habitat restoration in the Huron‐Erie corridor is likely resulting in increased habitat for the large lake sturgeon population in the system and in maintenance of the population's genetic diversity.
    Keywords Acipenser fulvescens ; DNA ; adults ; artificial reefs ; founder effect ; genetic variation ; genotype ; habitat conservation ; habitat destruction ; habitats ; larvae ; microsatellite repeats ; population ; population size ; reefs ; rivers ; spawning ; tail ; Great Lakes
    Language English
    Dates of publication 2015-07
    Size p. 455-464.
    Publishing place Wiley Periodicals, Inc.
    Document type Article
    ZDB-ID 914746-9
    ISSN 1526-100X ; 1061-2971
    ISSN (online) 1526-100X
    ISSN 1061-2971
    DOI 10.1111/rec.12200
    Database NAL-Catalogue (AGRICOLA)

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