Perry, Stephen

Northeast Aquatic Connectivity - An Assessment of Dams on Northeastern Rivers: Throughout the Northeast, hundreds of dams have been removed and hundreds of culverts have been replaced or retrofitted over the last two decades in projects where ecological restoration was a goal. To many working in the field of aquatic resource management it is apparent that given likely future constraints on availability of funds and staffing, it will be critical to be more strategic about investments in connectivity restoration projects. One approach to strategic investment is to assess the likely ecological “return on investment” associated with connectivity restoration. In order to complete an assessment at the regional scale, the Northeast Association of Fish and Wildlife Agencies (NEAFWA) awarded the Nature Conservancy (TNC) a 2007 Regional Conservation Needs (RCN) Grant. This RCN grant was designed to have TNC support state resource agencies in the Northeast U.S. (fish and wildlife, marine fisheries, dam safety, etc.) in efforts to strategically reconnect fragmented river, stream, coastal, reservoir, lake and estuarine habitat by removing or bypassing key barriers to fish passage. The primary ecological goal of mitigating fish passage barriers is to enhance populations of fish including anadromous fish, coldwater species, and other species of greatest conservation need (SGCN).
Located in Science and Data / Brook Trout Related Publications
Chesapeake Fish Passage Prioritization: An Assessment of Dams in the Chesapeake Bay Watershed: The Chesapeake Fish Passage Prioritization (CFPP or “the project”) project grew out of and builds on the conceptual framework of the Northeast Aquatic Connectivity.
Located in Science and Data / Brook Trout Related Publications
SEACAP: Southeast Aquatic Connectivity Assessment Project: Assessing the ecological impact of dams on Southeastern rivers: The Southeast Aquatic Connectivity Assessment Project (SEACAP) grew out of and builds on the conceptual framework of the Chesapeake Fish Passage Prioritization Project and the Northeast Aquatic Connectivity Project.
Located in Science and Data / Brook Trout Related Publications
Evaluating the Barrier Assessment Technique Derived from FishXing Software and the Upstream Movement of Brook Trout through Road Culverts: Anthropogenic barriers to fish passage, such as culverts and dams, are major factors impeding the persistence and recovery of aquatic species. Considerable work has focused on mitigating these impacts; however, activities associated with measuring and restoring connectivity of aquatic ecosystems often face challenges in determining the passability of barriers by aquatic species. Hydrological modeling software that incorporates biological aspects of a focal species is often used as a relatively inexpensive method for assessing barrier passability for restoration decisions. However, the biological relevance of these approaches remains to be rigorously tested. We assessed passage rates of PIT-tagged Brook Trout Salvelinus fontinalis through four road culverts and adjacent reference sites (unaltered areas of the streams) on the island of Newfoundland to determine whether upstream passage through road culverts was more restrictive than unaltered reference areas of the stream. Next, we examined the usefulness of barrier passability predictions derived from FishXing software by comparing them with in situ movement data for this species. Brook Trout passage for three of the four reference sites had a significantly higher range of passable stream flows compared with that for culverts, indicating the presence of velocity barriers in culverts. However, FishXing predictions of suitable fish passage discharges were conservative, and tagged fish successfully navigated partial barriers that were at least 2–3 times the upper limits of stream flow predicted to allow successful passage. The results of our study show a clear need for an improved understanding of fish movement through these structures so that barrier assessment techniques can be refined. The implications of not doing so may lead to restoration actions that result in limited biological benefit.
Located in Science and Data / Brook Trout Related Publications
Modified Culvert Inventory and Assessment Protocol: This culvert inventory and assessment method is a modified version of the National Inventory and Assessment Procedure (NIAP; Clarkin et al 2003) developed to collect data needed to run coarse filter evaluations of fish passage (Coffman 2005).
Located in Science and Data / Brook Trout Related Publications
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
Evaluation of Catch-and-Release Regulations on Brook Trout in Pennsylvania Streams: In 2004, the Pennsylvania Fish and Boat Commission implemented catch-and-release (CR) regulations on headwater stream systems to determine if eliminating angler harvest would result in an increase in the number of adult (≥100 mm) or large (≥175 mm) Brook Trout Salvelinus fontinalis. Under the CR regulations, angling was permitted on a year-round basis, no Brook Trout could be harvested at any time, and there were no tackle restrictions. A before-after–control-impact design was used to evaluate the experimental regulations. Brook Trout populations were monitored in 16 treatment (CR regulations) and 7 control streams (statewide regulations) using backpack electrofishing gear periodically for up to 15 years (from 1990 to 2003 or 2004) before the implementation of the CR regulations and over a 7–8-year period (from 2004 or 2005 to 2011) after implementation. We used Poisson mixed models to evaluate whether electrofishing catch per effort (CPE; catch/100 m2) of adult (≥100 mm) or large (≥175 mm) Brook Trout increased in treatment streams as a result of implementing CR regulations. Brook Trout CPE varied among sites and among years, and there was no significant effect (increase or decrease) of CR regulations on the CPE of adult or large Brook Trout. Results of our evaluation suggest that CR regulations were not effective at improving the CPE of adult or large Brook Trout in Pennsylvania streams. Low angler use, high voluntary catch and release, and slow growth rates in infertile headwater streams are likely the primary reasons for the lack of response.
Located in Science and Data / Brook Trout Related Publications
Movement Patterns of Brook Trout in a Restored Coastal Stream System in Southern Massachusetts: Populations of anadromous brook trout can be found from northern Canada into New England. It is believed that the extent of anadromy exhibited by coastal brook trout populations decreases with latitude, but the ecology and movements of the more southern populations are less studied. A 33-month acoustic telemetry study of anadromous brook trout (Salvelinus fontinalis) was conducted in a restored coastal stream and adjacent marine system in southeastern Massachusetts. Movement and migration patterns of 54 brook trout were investigated for individual differences and common features. Individuals exhibited a range of movement patterns. Some were more resident and only moved short distances, while others moved great distances covering the entire stretch of the stream (7.25 km) and moving into the marine environment. General Additive Mixed Models revealed that date was the major influence on brook trout movement between habitats and predicted peaks in movement in the spring and fall. Downstream movement peaked in the spring and in the fall, suggesting post-spawning feeding migration. Fish transitioned between habitats more often at new and full moons and when stream temperature was between 8 and 12 °C. Upstream transitions peaked as temperatures declined in winter 2011. Fifty percent of tagged brook trout were detected in the estuary during the study, suggesting that it is an important habitat for the population. In summer 2012, 14 tagged brook trout (20% of active tags) resided near one receiver at the head of the tide, which contained a thermal refugium in the form of a cold-water spring seep. Of the 84 tagged brook trout, 9.5% moved to the marine environment. Warm temperatures in saline Buttermilk Bay in the summer and cold temperatures in winter probably discourage some individuals from entering the marine environment. Compared to more northern coastal populations of brook trout, the Red Brook population appears to be less anadromous.
Located in Science and Data / Brook Trout Related Publications
Metabolic rates of embryos and alevin from a cold-adapted salmonid differ with temperature, population and family of origin: implications for coping with climate change: Early developmental stages of cold-adapted ectotherms such as brook trout (Salvelinus fontinalis) are at higher risk of mortality with increasing water temperatures. To determine the amount of variation present in early life, which may allow for potential adaptation to increasing temperature, we examined the routine metabolic rates (RMR) of wild-origin brook trout embryos and alevins reared at normal (5°C) and elevated (9°C) temperatures. The experiment was structured to examine variation in RMR within and among several levels of biological organization (family, population and ancestral type (native vs. mixed ancestry)). As expected, family and temperature variables were most important for predicting RMR and body mass, although population-level differences also existed when family was excluded for more detailed analysis. Additionally, body mass strongly influenced RMR at all life stages except for eyed embryos. When family identity was removed from the analysis, population became the most significant variable. Variation in RMR and mass within and among populations may indicate existing adaptive potential within and among brook trout populations to respond to predicted warming under climate change scenarios.
Located in Science and Data / Brook Trout Related Publications

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