Download or read book Effect of Change in Habitat Quality on Brook Trout Distribution and Abundance in Two Western Virginia Streams written by John R. Jordan (Jr.) and published by . This book was released on 1998 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Comparison of Brook Trout Populations and Habitat Parameters Between Eastern Kentucky Stocked Streams and Native Virginia Streams written by Grayson Richard Patton and published by . This book was released on 2010 with total page 88 pages. Available in PDF, EPUB and Kindle. Book excerpt: In 1968, the United States Fish and Wildlife Service stocked two streams, located in Wolfe County, Kentucky with brook trout (Salvelinus fontinalis) with hopes of establishing naturally reproducing populations. Shortly thereafter, four other brook trout populations were established. Very little is known about these populations and some biologists are skeptical to their contemporary existence. This study assessed Kentucky's introduced brook trout to determine their present day distribution and abundance, and then determined how each stream and population compares to two reference streams with native populations of brook trout located in Grayson County, Virginia. Brook trout were captured at each stream using a backpack electrofisher, and total lengths and weights were measured. Water temperature was collected using data loggers placed in each stream and riparian canopy cover was estimated using a vertical densiometer. In addition, air temperature and rainfall data were gathered from local weather stations. Brook trout were located in three out of five surveyed Kentucky streams, including young-of-the-year individuals, which provided evidence for natural reproduction. Virginia reference streams tended to have higher abundances (VA Catch per unit effort (CPUE) 38 and 41 brook trout/hour; KY CPUE's 6, 19 and 12 brook trout/hour) and relative weights (F=5.1316, P
Download or read book Brook Trout Populations in Headwater Stream Networks written by Yoichiro Kanno and published by . This book was released on 2011 with total page 228 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Habitat Suitability Index Model for Brook Trout in Streams of the Southern Blue Ridge Province written by Christopher J. Schmitt and published by . This book was released on 1993 with total page 66 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book General Technical Report RMRS written by and published by . This book was released on 1998 with total page 842 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Distribution and Habitat Use of Bull Trout Following the Removal of Nonnative Brook Trout written by Dirk Renner and published by . This book was released on 2005 with total page 122 pages. Available in PDF, EPUB and Kindle. Book excerpt: Invasion by nonnative brook trout (Salvelinus fontinalis) often results in replacement of bull trout (Salvelinus confluentus) in western North America, but the causal mechanisms are not well understood. Removal of brook trout from 1992 to 2000 from Sun Creek in southern Oregon, provided an opportunity to investigate the changes in distribution and abundance of bull trout. This study investigated bull trout distribution over from 1994 to 2003, during and following the extirpation of brook trout in 2000. In 2001 over, 8 km of contiguous stream habitat was examined to investigate bull trout habitat utilization. Bull trout abundance increased almost 300% after the removal of brook trout; however, bull trout distribution did not shift either upstream or downstream into habitat previously occupied by brook trout. This finding suggested that the occupied habitat was either critical for bull trout persistence or that factors restricted dispersal. Temperature did not appear to limit bull trout distribution remaining below 17°C with averages less than 10°C throughout Sun Creek. The downstream distribution of bull trout coincided with a point source increase of turbidity. In regions of the stream where turbidity was low bull trout abundance was positively associated with deep pools, higher average temperatures, and correlated with high densities of springs. The results of this study suggest that brook trout did not displace bull trout, underscoring the importance that point source disturbances (i.e. turbidity) can have on trout distributions. These findings reiterate the value of sampling contiguous streams as a means to identifying factors influencing trout distribution throughout a stream system.
Download or read book Variation in Trout Abundance in Relation to Habitat Quality in a Recently Disturbed Stream written by Ann D. Baker and published by . This book was released on 1989 with total page 112 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Effectiveness of Trout Habitat Restoration in Eustache Creek a Formerly Placer mined Stream in Western Montana written by Emily K. Thompson and published by . This book was released on 2010 with total page 72 pages. Available in PDF, EPUB and Kindle. Book excerpt: Aquatic ecosystems in the western U.S. have been severely degraded over the last century by anthropogenic activities such as mining, logging and grazing. Habitat heterogeneity in streams of the western United States has been lost as a result of both in-stream activities (i.e. dredging and straightening channels) and riparian zone activities (i.e. logging and vegetation removal). A commonly stated objective of stream channel restoration projects is to restore stream habitat quality and thereby improve aquatic species habitat and ultimately increase fish populations. The Ninemile drainage of the Clark Fork River watershed was historically a thriving native Bull trout and Westslope cutthroat trout (WCT) fishery. Intensive mining and logging activities throughout the watershed have severely impaired native fish habitat and reduced fish populations. In 2006, Lolo National Forest partnered with Trout Unlimited to restore a 1.3-mile section of Eustache Creek at the headwaters of the Ninemile drainage. This study used pre and post-restoration habitat and fish sampling data from 2005-2009 to analyze changes in habitat quality and fish abundance in three reaches of Eustache Creek. Habitat quality was assessed using six metrics: width to depth ratio, percent of pool habitat (based on site area), residual pool depth, large woody debris per 100 meters, large woody debris median diameter and percent fine sediment in pool tails. A repeated measures ANOVA model was used to detect significant increases in habitat quality and fish populations over the four-year period in Eustache Creek. A univariate ANOVA model was created to detect significant relationships between individual habitat quality variables and fish populations. Overall, statistical analysis does not necessarily point to a significant increase in habitat quality for Eustache Creek, and the restored stream condition is still far from its reference condition. However, a non-statistical assessment of trends in individual habitat metrics shows an improvement in trout habitat quality. There was a significant increase in total fish densities in Eustache Creek over the study period. Additionally, there was a significant increase in total WCT, Adult WCT, and Adult Eastern Brook trout (EBT) densities over time. However, there was no statistically significant difference in total fish density, total WCT density, adult WCT density, total EBT density and adult EBT density between reference and treatment reaches, indicating that the increased fish populations may reflect the influence of external factors such as climatic variability rather than the improvement in habitat quality. No habitat variables are significantly correlated to total fish density. There was a statistically weak positive correlation between percent pool habitat and total fish density.
Download or read book Strategies for Conserving Native Salmonid Populations at Risk from Nonnative Fish Invasions written by Kurt D. Fausch and published by . This book was released on 2006 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt: Native salmonid populations in the inland West are often restricted to small isolated habitats at risk from invasion by nonnative salmonids. However, further isolating these populations using barriers to prevent invasions can increase their extinction risk. This monograph reviews the state of knowledge about this tradeoff between invasion and isolation. We present a conceptual framework to guide analysis, focusing on four main questions concerning conservation value, vulnerability to invasion, persistence given isolation, and priorities when conserving multiple populations. Two examples illustrate use of the framework, and a final section discusses opportunities for making strategic decisions when faced with the invasion-isolation tradeoff.
Download or read book Environmental Factors Related to the Abundance and Distribution of Brook Trout Salvelinus Fontinalis and Brown Trout Salmo Trutta and Seasonal Movements of Brown Trout in Selected Virginia Streams written by Daniel C. Josephson and published by . This book was released on 1983 with total page 340 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Movement Patterns and Multi scale Factors that Influence Exotic Brook Trout and Endemic Bonneville Cutthroat Trout Distribution and Abundance in the Mill Creek Drainage Utah written by Benjamin K. Nadolski and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Introduced brook trout (Salvelinus fontinalis) are implicated as a primary factor leading to the decline in distribution and abundance of native cutthroat trout (Oncorhynchus clarkii). However, not all introductions are successful, suggesting local conditions influence the success of invasions. Therefore, I sought to determine the multiscale factor(s) that influence brook trouts' invasion success of native Bonneville cutthroat trout (Oncorhynchus clarkii utah) habitats in Mill Creek, Utah. I conducted patch occupancy surveys to determine watershed-scale brook trout and cutthroat trout distribution. I also determined the relative abundance of brook trout and cutthroat trout at the reach-scale by conducting three-pass depletion electrofishing surveys at ten index sites throughout the drainage. Upon completion of those surveys, I collected key watershed and reach-scale biotic and abiotic data twice during base-flow conditions. In addition, to determine watershed-scale population connectivity and the potential for upstream invasion by brook trout, I assessed fish movement using two-way weir traps. At the watershed-scale, stream slope appeared to limit brook trout invasion into some portions of the drainage. Intermittent stream-flows and extreme levels of stream slope (> 10%) appeared to limit cutthroat trout distribution. At the reach-scale, regression analyses indicated aquatic invertebrate abundance and low winter water temperatures may have influenced the abundance of brook trout, but my models explained little variation in cutthroat trout abundance overall. I observed high rates (74%) of site fidelity amongst brook trout, and mobile brook trout moved short distances (range=62-589 meters) overall. Cutthroat trout also exhibited high site fidelity (92%), but their movement was more variable, as few individuals moved long distances (up to 12.15 km). These findings will help prioritize cutthroat trout management actions in this watershed, and will be useful in determining why brook trout are successful invaders in some systems, yet remain in low and patchy abundance in others.
Download or read book Potential Climate and Land Use Change Effects on Brook Trout in the Eastern United States written by Jefferson Deweber and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Brook Trout is a socially, economically and ecologically important species throughout its native range in the eastern U.S. that is expected to be negatively affected by climate and land use change. In this dissertation, I use publicly available data to identify the potential effects of projected climate and land use change on river water temperature and Brook Trout populations in individual stream reaches throughout the eastern U.S. In Chapter 1, I quantitatively assessed the representativeness of stream flow and water temperature data from U. S. Geological Survey (USGS) gages throughout subregions of the conterminous United States, including the eastern U.S. In Chapter 2, I developed a model to predict river water temperatures under current conditions and future scenarios of climate and land use change. The final model included air temperature, landform attributes and forested land cover, and predicted mean daily water temperatures with good accuracy (root mean squared error ~ 1.9 °C) for training and validation datasets. In Chapter 3, I predicted Brook Trout occurrence probability based on water temperature predictions and selected landscape characteristics using a hierarchical logistic regression model that performed well at both training and validation datasets (area under the receiver operating curve ~ 0.78). In Chapter 4, I identified potential changes in thermal habitat and Brook Trout occurrence probability resulting from projected climate and land use change. The timing, magnitude and location of predicted changes in maximum 30 day mean river water temperature varied greatly among three downscaled climate models, with average increases ranging from 1.21 to 2.55 °C by 2087. As a result of warming, between 56,440 (42.7%) and 109,237 (82.6%) of potential Brook Trout habitat was predicted to be lost. Land use change was predicted to result in localized increases in river water temperature and losses of 4.5% of potential Brook Trout habitat. Given the magnitude of predicted losses, conservation actions will likely be more successful in the long term if the potential changes resulting from climate and land use change are incorporated into the planning process.
Download or read book Physical Habitat Factors Influencing the Distribution and Abundance of Rainbow Trout and Brown Trout in the Little Truckee River written by Jeffrey Lynn Kershner and published by . This book was released on 1991 with total page 266 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Habitat Suitability Index Models written by Robert F. Raleigh and published by . This book was released on 1982 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Habitat Suitability Index Models and Instream Flow Suitability Curves written by Robert F. Raleigh and published by . This book was released on 1986 with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Assessing Populations of Eastern Brook Trout Salvelinus Fontinalis Above and Below Waterfalls in Mountain Streams of Virginia written by and published by . This book was released on 2019 with total page 93 pages. Available in PDF, EPUB and Kindle. Book excerpt: Anthropogenically driven factors, such as increasing temperature and sediment in valley streams, acidification of mountain streams, and the introduction of non-native trout, are restricting habitat suitable for healthy populations of eastern brook trout (Salvelinus fontinalis) throughout their native Appalachian range. Brook trout are important as predators of insects in mountain streams and as a favorite of anglers. It is crucial that remaining populations in sustainable habitats be identified and preserved. Waterfalls are geologic knickpoints preventing base-level lowering that create unique, stable landscapes above them, which may alleviate the temperature-productivity/acidity "habitat squeeze" for populations of brook trout and could serve as potentially ideal targets for conservation efforts despite being isolated. This study investigates brook trout occurrence above waterfalls in Virginia and compares brook trout populations found above waterfalls to those below them. One-hundred meter reaches above and below seven waterfalls in Virginia's George Washington and Jefferson National Forest were sampled for brook trout via 3-pass, block-netted, backpack electrofishing depletions. All brook trout were counted, weighed, and measured for fork length. The response variables are differences in 1) percent dominance, 2) population size, 3) biomass, and 4) length-weight index (Fulton's Condition Factor) between brook trout above and below waterfalls. Brook trout dominance (100 vs. 36.9%) is greater above than below waterfalls, but not significantly (p = 0.1003). We found abundance (26 vs.12 individuals per 100m) and overall biomass (885.3 vs 284.6 grams per 100m) of brook trout populations above waterfalls to be significantly greater than their below waterfall counterparts (p = 0.078 for both). We also found brook trout above waterfalls to have a higher condition factor (1.086g/cm3 vs 1.0636g/cm3) than those below waterfalls (p = 0.031). Lastly, we found populations above waterfalls where their occurrence was previously unknown. Despite being isolated, brook trout populations above waterfalls were just as if not more robust than those below and may be excellent targets for conservation.
Download or read book A Watershed scale Monitoring Protocol for Bull Trout written by Dan Isaak and published by . This book was released on 2009 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt:
