Skip to content. | Skip to navigation

Personal tools
You are here: Home

Search results

44 items matching your search terms.
Filter the results.
Item type

New items since

Sort by relevance · date (newest first) · alphabetically
Restoring Aquatic Organism Passage within Wolf Laurel Branch, NC
This project will replace the existing double culverts with a bottomless structure to provide passage for brook trout and native nongame species. Replacement of these culverts will eliminate all artificial barriers within the Sand Creek drainage and reconnect existing populations of southern strain brook trout within approximately 2 miles of suitable habitat.
Located in Projects / 2006 - 2018 Projects / 2012 Projects
Brook Trout Catchment Scale and Climate Change Vulnerability Assessment
Climate change is currently a high risk threat to the current range of the brook trout due to changing thermal regimes. The effects of climate change may be exacerbated by greater fragmentation from land use changes. In order to effectively rank projects and work strategically, the Eastern Brook Trout Joint Venture is working on refining the status map to the catchment scale and establishing climate change resiliency rankings for brook trout populations throughout the partnership boundary from Georgia to Maine. JMU in partnership with the U.S. Forest Service and the Service have initiated efforts to determine resiliency rankings for brook trout populations in Virginia, Maryland and West Virginia. This project will allow the partnership to expand this analysis to cover all brook trout habitat from Georgia to Maine.
Located in Projects / 2006 - 2018 Projects / 2012 Projects
File chemical/x-pdb Tipton Creek Culvert Replacement, NC_FY10 Project
In the summer of 2011 the culvert at the Davis Creek Road (FSR 420) crossing of Tipton Creek was removed and replaced with a concrete arch, stream simulation crossing for the purpose of passing aquatic organisms, where the existing culvert was known to be a barrier to aquatic passage due to velocity and outlet drop. The crossing was sized using the 100-year flow calculation derived from the USGS Regression Equation for the mountains of North Carolina. Additionally, the width of the crossing was designed to accommodate a bankfull flow channel dimension plus a small area of floodplain. The channel was reconstructed through the crossing using the dimension, pattern, and profile of the reference reach upstream. The new channel was constructed using imported boulders and onsite alluvial materials. Grass seed was sown, and trees and shrubs were planted, both potted and live-stakes. Over the last year since construction, the site has experienced several small flood events. The site remains stable, passable to all aquatic species, and looks more and more natural every year as planted and natural vegetation establishes.
Located in Projects / Project Completion Reports
File chemical/x-pdb Jam Black Brook Culvert Replacement, ME_FY12 Project
The goals of the project were: (1) To remove an obstruction to upstream fish passage for brook trout, Atlantic salmon and other resident and migratory fish. (2) To restore access to 9.8 miles of stream habitat upstream of the obstruction. (3) To restore natural sediment and woody debris transport through the crossing site. (4) To improve flood capacity at the Magog Road crossing, reducing the risk of debris jams or overtopping the road. (5) To provide a demonstration site in mid‐coast Maine for an appropriate stream crossing developed in cooperation with the municipality.
Located in Projects / Project Completion Reports
File Estimating size-specific brook trout abundance in continuously sampled headwater streams using Bayesian mixed models with zero inflation and overdispersion
We examined habitat factors related to reach-scale brook trout Salvelinus fontinalis counts of four size classes in two headwater stream networks within two contrasting summers in Connecticut, USA. Two study stream networks (7.7 and 4.4 km) were surveyed in a spatially continuous manner in their entirety, and a set of Bayesian generalised linear mixed models was compared. Trout abundance was best described by a zero-inflated overdispersed Poisson model. The effect of habitat covariates was not always consistent among size classes and years. There were nonlinear relationships between trout counts and stream temperature in both years. Colder reaches harboured higher trout counts in the warmer summer of 2008, but this pattern was not observed in the cooler and very wet summer of 2009. Amount of pool habitat was nearly consistently important across size classes and years, and counts of the largest size class were correlated positively with maximum depth and negatively with stream gradient. Spatial mapping of trout distributions showed that reaches with high trout counts may differ among size classes, particularly between the smallest and largest size classes, suggesting that movement may allow the largest trout to exploit spatially patchy habitats in these small headwaters.
Located in Science and Data / Brook Trout Related Publications
File Population regulation of brook trout (Salvelinus fontinalis) in Hunt Creek, Michigan: a 50-year study
1. Fisheries models generally are based on the concept that strong density dependence exists in fish populations. Nonetheless, there are few examples of long-term density dependence in fish populations. 2. Using an information theoretical approach (AIC) with regression analyses, we examined the explanatory power of density dependence, flow and water temperature on the per capita rate of change and growth (annual mean total length) for the whole population, adults, 1+ and young-of-the-year (YOY) brook trout (Salvelinus fontinalis) in Hunt Creek, Michigan, USA, between 1951 and 2001. This time series represents one of the longest quantitative population data sets for fishes. 3. Our analysis included four data sets: (i) Pooled (1951–2001), (ii) Fished (1951–65), (iii) Unfished (1966–2001) and (iv) Temperature (1982–2001). 4. Principle component analyses of winter flow data identified a gradient between years with high mean daily winter flows, high daily maximum and minimum flows and frequent high flow events, and years with an opposite set of flow characteristics. Flows were lower during the Fished Period than during the Unfished Period. Winter temperature analyses elucidated a gradient between warm mean, warm minimum and maximum daily stream temperatures and a high number of minimum daily temperatures >6.1 C, and years with the opposite characteristics. Summer temperature analyses contrasted years with warm summer stream temperatures vs years with cool summer stream temperatures. 5. Both YOY and adult densities varied several-fold during the study. Regression analysis did not detect a significant linear or nonlinear stock–recruitment relationship. AIC analysis indicated that density dependence was present in 15 of 16 cases (four population segments · four data sets) for both per capita rate of increase (wi values 0.46–1.00) and growth data (wi values 0.28–0.99). The almost ubiquitous presence of density dependence in both population and growth data is concordant with results from other trout populations and other studies in Michigan.
Located in Science and Data / Brook Trout Related Publications
File Brook Trout Movement in Response to Temperature, Flow, and Thermal Refugia within a Complex Appalachian Riverscape
We quantified movements of brook trout Salvelinus fontinalis and brown trout Salmo trutta in a complex riverscape characterized by a large, open-canopy main stem and a small, closed-canopy tributary in easternWest Virginia, USA. Our objectives were to quantify the overall rate of trout movement and relate movement behaviors to variation in streamflow, water temperature, and access to coldwater refugia. The study area experienced extremely high seasonal, yearly, and among-stream variability in water temperature and flow. The relative mobility of brook trout within the upper Shavers Fork watershed varied significantly depending on whether individuals resided within the larger main stem or the smaller tributary. The movement rate of trout inhabiting the main stem during summer months (50 m/d) was an order of magnitude higher than that of tributary fish (2 m/d). Movement rates of main-stem-resident brook trout during summer were correlated with the maximum water temperature experienced by the fish and with the fish’s initial distance from a known coldwater source. For main-stem trout, use of microhabitats closer to cover was higher during extremely warm periods than during cooler periods; use of microhabitats closer to cover during warm periods was also greater for main-stem trout than for tributary inhabitants. Main-stem-resident trout were never observed in water exceeding 19.5◦C. Our study provides some of the first data on brook trout movements in a large Appalachian river system and underscores the importance of managing trout fisheries in a riverscape context. Brook trout conservation in this region will depend on restoration and protection of coldwater refugia in larger river main stems as well as removal of barriers to trout movement near tributary and main-stem confluences.
Located in Science and Data / Brook Trout Related Publications
File 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
File text/texmacs A Function-Based Framework for Stream Assessment & Restoration Projects
Stream restoration efforts have increased significantly in the US over the past few decades and are now recognized as a billion-dollar industry. These restoration efforts stem from centuries of abuse as humans continue to alter the riverine landscape for a variety of purposes, including farming, logging, mining and development on the floodplain, and the subsequent need for channelization and flood control. These activities have significantly diminished the natural functions of our stream corridors. Today stream corridor restoration efforts seek to improve or restore these lost functions. A variety of federal, state and local programs, along with efforts from non-profit organizations, provide funding for these programs. The goals are varied and range from simple streambank stabilization projects to watershed scale restoration. For these projects to be successful it is important to know why the project is being completed and what techniques are best suited to restore the lost functions. Knowing why a project is needed requires some form of functional assessment followed by clear project goals. To successfully restore stream functions, it is necessary to understand how these different functions work together and which restoration techniques influence a given function. It is also imperative to understand that stream functions are interrelated and build on each other in a specific order, a functional hierarchy. If this hierarchy is understood, it is easier to establish project goals. And with clearer goals, it is easier to evaluate project success.
Located in Science and Data / Brook Trout Related Publications / Stream Assessment and Monitoring
File Sampling strategies for estimating brook trout effective population size
The influence of sampling strategy on estimates of effective population size (Ne) from single-sample genetic methods has not been rigorously examined, though these methods are increasingly used. For headwater salmonids, spatially close kin association among age-0 individuals suggests that sampling strategy (number of individuals and location from which they are collected) will influence estimates of Ne through family representation effects. We collected age-0 brook trout by completely sampling three headwater habitat patches, and used microsatellite data and empirically parameterized simulations to test the effects of different combinations of sample size (S = 25, 50, 75, 100, 150, or 200) and number of equally-spaced sample starting locations (SL = 1, 2, 3, 4, or random) on estimates of mean family size and effective number of breeders (Nb). Both S and SL had a strong influence on estimates of mean family size and ^ Nb; however the strength of the effects varied among habitat patches that varied in family spatial distributions. The sampling strategy that resulted in an optimal balance between precise estimates of Nb and sampling effort regardless of family structure occurred with S = 75 and SL = 3. This strategy limited bias by ensuring samples contained individuals from a high proportion of available families while providing a large enough sample size for precise estimates. Because this sampling effort performed well for populations that vary in family structure, it should provide a generally applicable approach for genetic monitoring of iteroparous headwater stream fishes that have overlapping generations.
Located in Science and Data / Brook Trout Related Publications / Stream Assessment and Monitoring