Perry, Stephen

F18AC00818 Interim Performance Report: 4/1/2019 – 9/30/2019: This report describes accomplishments made under this FWS Service Agreement.
Located in Projects / EBTJV Operational Grants / FY18 EBTJV Coordination and Operations_FWS-NFHAP Funded Agreement
Fall and Early Winter Movement and Habitat Use of Wild Brook Trout: Brook Trout Salvelinus fontinalis populations face a myriad of threats throughout the species’ native range in the eastern United States. Understanding wild Brook Trout movement patterns and habitat requirements is essential for conserving existing populations and for restoring habitats that no longer support self-sustaining populations. To address uncertainties related to wild Brook Trout movements and habitat use, we radio-tracked 36 fish in a headwater stream system in central Pennsylvania during the fall and early winter of 2010–2011.We used generalized additive mixed models and discrete choice models with random effects to evaluate seasonal movement and habitat use, respectively. There was variability among fish in movement patterns; however, most of the movement was associated with the onset of the spawning season and was positively correlated with fish size and stream flow. There was heterogeneity among fish in selection of intermediate (0.26–0.44 m deep) and deep (0.44–1.06 m deep) residual pools, while all Brook Trout showed similar selection for shallow (0.10–0.26 m) residual pools. There was selection for shallow residual pools during the spawning season, followed by selection for deep residual pools as winter approached. Brook Trout demonstrated a threshold effect for habitat selection with respect to pool length, and selection for pools increased as average pool length increased up to approximately 30 m, and then use declined rapidly for pool habitats greater than 30 m in length. The heterogeneity and nonlinear dynamics of movement and habitat use of wild Brook Trout observed in this study underscores two important points: (1) linear models may not always provide an accurate description of movement and habitat use, which can have implications for management, and (2) maintaining stream connectivity and habitat heterogeneity is important when managing self-sustaining Brook Trout populations.
Located in Science and Data / Brook Trout Related Publications
February 2008 NFH Board Meeting Summary: This document summarizes the National Fish Habitat Board's February 20-21, 2008 meeting.
Located in About EBTJV / National Fish Habitat Board Meetings / 2008 NFH Board Meetings
February 2013 NFH Board Meeting Book: This document contains materials associated with the National Fish Habitat Board's February 26 - 27, 2013 in-person meeting.
Located in About EBTJV / National Fish Habitat Board Meetings / 2013 NFH Board Meetings
Fisheries - Responding to Drought and Water Challenges: A presentation of coldwater fisheries and climate adaptation case studies in the Eastern and Western United States.
Located in The Story of Wild Brook Trout / Brook Trout Video and Webinar Gallery
Fragmentation and Patch Size Shape Genetic Structure of Brook Trout Populations: We tested the relative influence of habitat patch size and connectivity on genetic structure and effective population size in eight brook trout (Salvelinus fontinalis) habitat patches in a watershed in Virginia, USA. Variation at eight microsatellite loci in 2229 young-of-the-year brook trout for two successive cohorts (2010 and 2011) was examined. Genetic differentiation across all populations was pronounced. Overall F'ST was 0.397 (95% CI: 0.322–0.525) and overall FST was 0.124 (95% CI: 0.096–0.159). Above-barrier patch size had a strong positive relationship with genetic diversity, Nˆ b, and genetic differentiation. Our analysis is consistent with greater extinction risk in smaller above-barrier patches. Larger above-barrier patches contained greater genetic diversity but reduced Nˆ b relative to adjacent below-barrier patches. The primary effect of barriers may be to reduce available above-barrier spawning habitat, even for larger above-barrier patches. Below-barrier patches also showed evidence of reduced genetic diversity and lack of connectivity. Genetic monitoring focused at gaining a broader understanding of the relationships here will be necessary to fully evaluate local extinction risks.
Located in Science and Data / Brook Trout Related Publications / Brook Trout Genetics Research
Fragmentation and Patch Size Shape Genetic Structure of Brook Trout Populations: We tested the relative influence of habitat patch size and connectivity on genetic structure and effective population size in eight brook trout (Salvelinus fontinalis) habitat patches in a watershed in Virginia, USA. Variation at eight microsatellite loci in 2229 young-of-the-year brook trout for two successive cohorts (2010 and 2011) was examined. Genetic differentiation across all populations was pronounced. Overall F'ST was 0.397 (95% CI: 0.322–0.525) and overall FST was 0.124 (95% CI: 0.096–0.159). Above-barrier patch size had a strong positive relationship with genetic diversity, Nˆ b, and genetic differentiation. Our analysis is consistent with greater extinction risk in smaller above-barrier patches. Larger above-barrier patches contained greater genetic diversity but reduced Nˆ b relative to adjacent below-barrier patches. The primary effect of barriers may be to reduce available above-barrier spawning habitat, even for larger above-barrier patches. Below-barrier patches also showed evidence of reduced genetic diversity and lack of connectivity. Genetic monitoring focused at gaining a broader understanding of the relationships here will be necessary to fully evaluate local extinction risks.
Located in Science and Data / Brook Trout Related Publications
FY14 EBTJV Coordination and Operations_FWS-NFHAP Funded Agreement: This folder contains documents related to the EBTJV's FY14 Coordination and Operations agreement supported by FWS-NFHAP Funds.
Located in Projects / EBTJV Operational Grants
FY15 EBTJV Coordination and Operations_FWS-NFHAP Funded Agreement: This folder contains documents related to the EBTJV's FY15 Coordination and Operations agreement supported by FWS-NFHAP Funds.
Located in Projects / EBTJV Operational Grants
FY15 Scope of Work: This document describes the EBTJV Coordinator's scope of work supported by FY15 FWS-NFHAP funds.
Located in About EBTJV / EBTJV Management / EBTJV Coordinator - Scope of Work Descriptions

« Previous 10 items Next 10 items » 1 ... 19 20 21 [22] 23 24 25 ... 38

Sections

Personal tools

Search results