Perry, Stephen

Is motivation important to brook trout passage through culverts?: Culverts can restrict movement of stream-dwelling fish. Motivation to enter and ascend these structures is an essential precursor for successful passage. However, motivation is challenging to quantify. Here, we use attempt rate to assess motivation of 447 brook trout (Salvelinus fontinalis) entering three culverts under a range of hydraulic, environmental, and biological conditions. A passive integrated transponder system allowed for the identification of passage attempts and success of individual fish. Attempt rate was quantified using time-to-event analysis allowing for time-varying covariates and recurrent events. Attempt rate was greatest during the spawning period, at elevated discharge, at dusk, and for longer fish. It decreased during the day and with increasing number of conspecifics downstream of the culvert. Results also show a positive correlation between elevated motivation and successful passage. This study enhances understanding of factors influencing brook trout motivation to ascend culverts and shows that attempt rate is a dynamic phenomenon, variable over time and among individuals. It also presents methods that could be used to investigate other species’ motivation to pass natural or anthropogenic barriers.
Located in Science and Data / Brook Trout Related Publications
Evaluation of Wild Brook Trout Populations in Vermont Streams: Wild brook trout populations in Vermont streams appeared to be relatively stable over a period of five decades as evidenced in this evaluation of 150 sites. Present-day brook trout populations sampled in 138 streams within 17 watersheds were characterized by abundant natural reproduction and multiple age-classes, including the contribution of older, larger fish. While most population measures were consistent between the two time periods, significantly higher densities of young-of-year brook trout were observed in current populations which may reflect improved environmental protections initiated since the 1950s. A decline in sympatric brown trout and rainbow trout sites also suggest that non-native trout populations have not appreciably expanded over the past 50 years.
Located in Science and Data / Brook Trout Related Publications
January 2020 NFH Board Meeting Summary: This document summarizes the National Fish Habitat Board's January 15, 2020 meeting that was conducted by teleconference.
Located in About EBTJV / National Fish Habitat Board Meetings / 2020 NFH Board Meetings
2020 NFH Board Meetings: This folder contains the 2020 NFH Board Meeting Books and/or Meeting Summaries.
Located in About EBTJV / National Fish Habitat Board Meetings
October 2019 NFH Board Meeting Summary: This document summarizes the National Fish Habitat Board's October 23 - 24, 2019 in-person meeting.
Located in About EBTJV / National Fish Habitat Board Meetings / 2019 NFH Board Meetings
June 2019 NFH Board Meeting Book: This document contains materials associated with the National Fish Habitat Board's June 19, 2019 meeting that was conducted by teleconference.
Located in About EBTJV / National Fish Habitat Board Meetings / 2019 NFH Board Meetings
March 2019 NFH Board Meeting Book: This document contains materials associated with the National Fish Habitat Board's March 20 - 21, 2019 in-person meeting.
Located in About EBTJV / National Fish Habitat Board Meetings / 2019 NFH Board Meetings
2019 NFH Board Meetings: This folder contains the 2019 NFH Board Meeting Books and/or Meeting Summaries.
Located in About EBTJV / National Fish Habitat Board Meetings
October 2018 NFH Board Meeting Book: This document contains materials associated with the National Fish Habitat Board's October 17 - 18, 2018 in-person meeting.
Located in About EBTJV / National Fish Habitat Board Meetings / 2018 NFH Board Meetings
June 2018 NFH Board Meeting Book: This document contains materials associated with the National Fish Habitat Board's June 27, 2018 meeting that was conducted by teleconference.
Located in About EBTJV / National Fish Habitat Board Meetings / 2018 NFH Board Meetings

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