Demography Of Lake Trout In Relation To Population Suppression In Yellowstone Lake Yellowstone National Park

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Demography of Lake Trout in Relation to Population Suppression in Yellowstone Lake, Yellowstone National Park

Author : John Michael Syslo
Publisher :
ISBN 13 :
Total Pages : 208 pages
Book Rating : 4.:/5 (651 download)

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Book Synopsis Demography of Lake Trout in Relation to Population Suppression in Yellowstone Lake, Yellowstone National Park by : John Michael Syslo

Download or read book Demography of Lake Trout in Relation to Population Suppression in Yellowstone Lake, Yellowstone National Park written by John Michael Syslo and published by . This book was released on 2010 with total page 208 pages. Available in PDF, EPUB and Kindle. Book excerpt: Introduced lake trout Salvelinus namaycush threaten to extirpate native Yellowstone cutthroat trout Oncorhynchus clarkii bouvieri in Yellowstone Lake, Yellowstone National Park. Suppression of the lake trout population is deemed necessary for the conservation of Yellowstone cutthroat trout. A National Park Service gill netting program removed nearly 273,000 lake trout from Yellowstone Lake between 1995 and 2007. Lake trout population size has not been estimated; therefore, it is difficult to determine the efficacy of the program (i.e., proportion of the population that has been removed). My objectives were to (1) examine catch per unit effort (C/f) through time and catch as a function of effort to determine if the suppression program has caused lake trout abundance to decline, (2) determine if length structure, age structure, individual growth, mortality, body condition, length at maturity, age at maturity, and fecundity have changed as a function of harvest, and (3) develop age-structured models to determine the level of mortality required to cause population growth rate to decline below 1.0 (replacement). An increase in lake trout abundance was indicated by increasing C/f over time. Additionally, catch has continued to increase as a function of effort, indicating lake trout abundance is increasing. Population metrics were not clearly indicative of a response to harvest. However, metrics were comparable to North American lake trout populations where harvest has occurred, indicating that lake trout have not reached carrying capacity in Yellowstone Lake. Results from an age-structured matrix model determined the rate of population growth was 1.1 given the current rate of fishing mortality and that population growth rate would be 1.3 in the absence of fishing mortality. The current rate of population growth is positive; however, it is slower than it would be in the absence of lake trout suppression. Fishing mortality needs to increase from the rate of 0.22 estimated in 2007 to at least 0.32 to reduce population growth rate below replacement. Lake trout suppression is becoming an increasingly common management practice throughout the Intermountain West. Thus, Yellowstone Lake provides a case study for evaluating a strategy to remove the apex predator from a large lake.

Response of Non-native Lake Trout (Salvelinus Namaycush) to 15 Years of Harvest in Yellowstone Lake, Yellowstone National Park

Author : John M. Syslo
Publisher :
ISBN 13 :
Total Pages : 14 pages
Book Rating : 4.:/5 (13 download)

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Book Synopsis Response of Non-native Lake Trout (Salvelinus Namaycush) to 15 Years of Harvest in Yellowstone Lake, Yellowstone National Park by : John M. Syslo

Download or read book Response of Non-native Lake Trout (Salvelinus Namaycush) to 15 Years of Harvest in Yellowstone Lake, Yellowstone National Park written by John M. Syslo and published by . This book was released on 2011 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt: Introduced lake trout (Salvelinus namaycush) threaten to extirpate native Yellowstone cutthroat trout (Oncorhynchus clarkii bouvieri) in the 34 000 ha Yellowstone Lake in Yellowstone National Park, USA. Suppression (and eventual eradication) of the lake trout population is deemed necessary for the conservation of Yellowstone cutthroat trout. A US National Park Service gill-netting program removed nearly 450 000 lake trout from Yellowstone Lake from 1995 through 2009. We examined temporal variation in individual growth, body condition, length and age at maturity, fecundity, mortality, and population models to assess the efficacy of the lake trout suppression program. Population metrics did not indicate overharvest despite more than a decade of fish removal. The current rate of population growth is positive; however, it is lower than it would be in the absence of lake trout suppression. Fishing effort needs to increase above observed levels to reduce population growth rate below replacement. Additionally, high sensitivity of population growth rate to reproductive vital rates indicates that increasing fishing mortality for sexually mature lake trout may increase the effectiveness of suppression. Lake trout suppression in Yellowstone Lake illustrates the complexities of trying to remove an apex predator to restore a relatively large remote lentic ecosystem with a simple fish assemblage.

Lake Trout Suppression in Yellowstone Lake

Author : Yellowstone National Park (Agency : U.S.)
Publisher :
ISBN 13 :
Total Pages : 31 pages
Book Rating : 4.:/5 (953 download)

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Book Synopsis Lake Trout Suppression in Yellowstone Lake by : Yellowstone National Park (Agency : U.S.)

Download or read book Lake Trout Suppression in Yellowstone Lake written by Yellowstone National Park (Agency : U.S.) and published by . This book was released on 2015 with total page 31 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Effects of Lake Trout Suppression Methods on Lower Trophic Levels in Yellowstone Lake, Wyoming

Author : Dominique Raquel Lujan
Publisher :
ISBN 13 :
Total Pages : 56 pages
Book Rating : 4.5/5 (699 download)

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Book Synopsis Effects of Lake Trout Suppression Methods on Lower Trophic Levels in Yellowstone Lake, Wyoming by : Dominique Raquel Lujan

Download or read book Effects of Lake Trout Suppression Methods on Lower Trophic Levels in Yellowstone Lake, Wyoming written by Dominique Raquel Lujan and published by . This book was released on 2020 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lake trout (Salvelinus namaycush) were unintentionally introduced to Yellowstone Lake, Yellowstone National Park, Wyoming, and drastically reduced the native Yellowstone cutthroat trout (Oncorhynchus clarkii bouvieri) population. Gillnetting suppresses adult lake trout since 1995; however, Yellowstone National Park is developing methods to suppress embryos, including adding lake trout carcasses and analog pellets to spawning sites. Decomposing carcasses and analog pellets cause lake trout embryo mortality due to low dissolved oxygen concentrations, but the effects of these methods on lower trophic levels are unknown. We estimated the degree to which adding carcasses or analog pellets to spawning sites altered nutrient limitation, nutrient concentrations, algal biomass, and ammonium uptake. We deployed nutrient diffusing substrates at three sites (control, carcass, and analog pellets) before and after carcasses or analog pellets were added to measure algal biomass in six treatments where nothing (control), nitrogen, phosphorus, nitrogen and phosphorus, carcasses or pellets were added to agar. We measured nutrient concentrations, algal biomass (chlorophyll a concentrations) and ammonium uptake at spawning sites where no carcasses were added (control), site where carcasses were added before lake trout spawned (early season sites), and sites where carcasses were added after lake trout spawned (late season sites) in 2018 and 2019 to investigate the degree to which carcasses caused bottom-up effects in periphyton and phytoplankton. Nutrient diffusing substrates indicated that nitrogen and phosphorus co-limited periphyton before treatments; however, nutrients were not limiting after carcasses or analog pellets were added to spawning sites. Analog pellets appeared to suppress algal biomass and carcasses increased algal biomass ≥2.4x after their addition. Adding carcasses to shallow spawning sites did not alter the concentration of ammonium, algal biomass or uptake compared to the control site. Periphyton had higher biomass and phytoplankton uptake was much higher. Adding carcasses to the littoral zone likely alters small areas but overall had a small effect on algal biomass and nutrient cycling. Estimating how lake trout suppression methods may alter basal resources in the littoral zone of Yellowstone Lake will help managers develop the best plan to control these invasive predators at early life stages.

The Lake Charr Salvelinus namaycush: Biology, Ecology, Distribution, and Management

Author : Andrew M. Muir
Publisher : Springer Nature
ISBN 13 : 3030622592
Total Pages : 526 pages
Book Rating : 4.0/5 (36 download)

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Book Synopsis The Lake Charr Salvelinus namaycush: Biology, Ecology, Distribution, and Management by : Andrew M. Muir

Download or read book The Lake Charr Salvelinus namaycush: Biology, Ecology, Distribution, and Management written by Andrew M. Muir and published by Springer Nature. This book was released on 2021-03-03 with total page 526 pages. Available in PDF, EPUB and Kindle. Book excerpt: The lake charr Salvelinus namaycush is a ubiquitous member of cold-water lake ecosystems in previously glaciated regions of northern continental U.S., Alaska, and Canada that often support important commercial, recreational, and subsistence fisheries. The lake charr differs from other charrs by its large size, longevity, iteroparity, top-predator specialization, reduced sexual dimorphism, prevalence of lacustrine spawning, and use of deepwater habitat. The species is remarkably variable in phenotype, physiology, and life history, some of which is reflected in its ecology and genetics, with as many as four morphs or ecotypes co-occurring in a single lake. The lake charr is often the top predator in these systems, but is highly adaptable trophically, and is frequently planktivorous in small lakes. The lake charr by their name highlights their common habitat, lakes both large and small, but often frequents rivers and occasionally moves into the Arctic Ocean. Movement and behaviour of lake charr are motivated by access to cool, well-oxygenated water, foraging opportunities, predator avoidance, and reproduction. Owing to their broad distribution and trophic level, the lake charr serves as a sentinel of anthropogenic change. This volume will provide an up-to-date summary of what is currently known about lake charr from distribution to genetics to physiology to ecology. The book provides a compilation and synthesis of available information on the lake charr, beginning with an updated distribution and a revised treatment of the paleoecology of the species. Understanding of ecological and genetic diversity and movement and behaviour of the species has advanced remarkably since the last major synthesis on the species over 40 years ago. Mid-sections of the book provide detailed accounts of the biology and life history of the species, and later sections are devoted to threats to conservation and fishery management practices used to ensure sustainability. A new standard lake charr-specific terminology is also presented. The book will be a valuable reference text for biologists around the world, ecologists, and fishery managers, and of interest to the angling public.

Migrate, Mutate, Or Die

Author : Sarah Gandhi-Besbes
Publisher :
ISBN 13 :
Total Pages : 51 pages
Book Rating : 4.:/5 (13 download)

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Book Synopsis Migrate, Mutate, Or Die by : Sarah Gandhi-Besbes

Download or read book Migrate, Mutate, Or Die written by Sarah Gandhi-Besbes and published by . This book was released on 2016 with total page 51 pages. Available in PDF, EPUB and Kindle. Book excerpt: Yellowstone National Park is a relatively pristine ecosystem preserved through time. The Yellowstone cutthroat trout Oncorhynchus clarkii bouvieri population, inhabiting shallower waters in Yellowstone Lake and spawning in its tributaries, has been declining primarily due to the introduction of a predatory fish. The lake trout Salvelinus namaycush, which rapidly grow to large sizes, feed on the Yellowstone cutthroat trout, breed and spawn in Yellowstone Lake, and dwell in deeper waters out of predatory reach. The Yellowstone cutthroat trout is relied upon both directly and indirectly by more than 40 species within Yellowstone National Park. The grizzly bear Ursus arctos horribilis, bald eagle Haliaeetus leucocephalus, and osprey Pandion halaetus all feed directly on the spawning fish. This study looks at how the declining Yellowstone cutthroat trout populations affect these predatory populations, and what their populations may look like should current trends continue into the year 2030. Conducting a meta-analysis and collecting primary data allowed for statistical projections predicting and comparing estimated future populations. The ecological change in Yellowstone Lake provides insight into how the concerns of one ecosystem affects multiple.

Yellowstone Lake Trout Creel Census, 1950-51

Author : Harvey L. Moore
Publisher :
ISBN 13 :
Total Pages : 48 pages
Book Rating : 4.:/5 (31 download)

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Book Synopsis Yellowstone Lake Trout Creel Census, 1950-51 by : Harvey L. Moore

Download or read book Yellowstone Lake Trout Creel Census, 1950-51 written by Harvey L. Moore and published by . This book was released on 1952 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Spawning Site Selection and Fry Development of Invasive Lake Trout in Yellowstone Lake, Yellowstone National Park, Wyoming

Author : Lee Gregory Simard
Publisher :
ISBN 13 :
Total Pages : 262 pages
Book Rating : 4.:/5 (13 download)

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Book Synopsis Spawning Site Selection and Fry Development of Invasive Lake Trout in Yellowstone Lake, Yellowstone National Park, Wyoming by : Lee Gregory Simard

Download or read book Spawning Site Selection and Fry Development of Invasive Lake Trout in Yellowstone Lake, Yellowstone National Park, Wyoming written by Lee Gregory Simard and published by . This book was released on 2017 with total page 262 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since their discovery in Yellowstone Lake in 1994, Lake Trout (Salvelinus namaycush) have been the object of an intensive gillnet suppression program due to their predation on native Yellowstone Cutthroat Trout (Oncorhynchus clarkii bouvieri). Managers are also interested in targeting early life stages to augment suppression. A benthic sled was used to sample for Lake Trout eggs at 24 locations, hypothesized to be spawning sites, that encompassed a range of depths, slopes, and substrate composition to determine the location and characteristics of spawning sites in Yellowstone Lake. Lake Trout eggs were collected at seven sites, five of which had not been previously confirmed as spawning sites. Habitat characterization at these sites indicate Lake Trout spawning in Yellowstone Lake is limited to areas with rocky substrate, but is not constrained to areas with interstitial spaces or contour breaks as is seen within the species'native range. Lake Trout fry were captured around Carrington Island, an additional spawning site in Yellowstone Lake, in 2014 and 2015. These fry were significantly larger at each developmental stage, consumed more food beginning at earlier stages, and were captured much later into the summer than fry captured at a spawning site in Lake Champlain. The lack of potential egg and fry predators in Yellowstone Lake could be driving these differences in spawning site selection and fry behavior. This information will allow managers to identify additional spawning locations for suppression and evaluate the impact their efforts might have on the Lake Trout population in Yellowstone Lake.

Dynamics of Yellowstone Cutthroat Trout and Lake Trout in the Yellowstone Lake Ecosystem

Author : John Michael Syslo
Publisher :
ISBN 13 :
Total Pages : 154 pages
Book Rating : 4.:/5 (926 download)

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Book Synopsis Dynamics of Yellowstone Cutthroat Trout and Lake Trout in the Yellowstone Lake Ecosystem by : John Michael Syslo

Download or read book Dynamics of Yellowstone Cutthroat Trout and Lake Trout in the Yellowstone Lake Ecosystem written by John Michael Syslo and published by . This book was released on 2015 with total page 154 pages. Available in PDF, EPUB and Kindle. Book excerpt: The introduction of lake trout Salvelinus namaycush into Yellowstone Lake preceded the collapse of the native Yellowstone cutthroat trout Oncorhynchus clarkii bouvieri population. As a system with a simple fish assemblage and several long-term data sets, Yellowstone Lake provided a unique opportunity to evaluate the ecology of a native salmonid in the presence of a non-native salmonid population undergoing suppression in a large natural lake. Diet data for Yellowstone cutthroat trout and lake trout were evaluated at varying densities to determine the effects of density on diet composition. Temporal diet shifts from 1996-1999 to 2011-2013 were likely caused by limitation of prey fish for lake trout. Diets, stable isotopes, and depth-related patterns in CPUE indicated lake trout> 300 mm consumed primarily amphipods, making them trophically similar to Yellowstone cutthroat trout from during 2011-2013. A lake trout removal program was initiated during 1995 to reduce predation on Yellowstone cutthroat trout. Abundance and fishing mortality were estimated for lake trout from 1998 through 2013 and Yellowstone cutthroat trout from 1986 through 2013. Density-dependence was evaluated by examining individual growth, weight, maturity, and pre-recruit survival as a function of abundance. In addition, a simulation model was developed for the lake trout- Yellowstone cutthroat trout system to determine the probability of Yellowstone cutthroat trout abundance persisting at performance metrics given potential reductions in lake trout abundance. Estimates of Yellowstone cutthroat trout abundance varied 5-fold and lake trout abundance varied 6-fold. Yellowstone cutthroat trout weight and pre-recruit survival decreased with increasing Yellowstone cutthroat trout abundance; however, individual growth and maturity were not related to abundance. Lake trout population metrics did not vary with lake trout abundance. Simulation model results were variable because of uncertainty in lake trout pre-recruit survival. Conservative estimates for required lake trout reductions were> 97% of 2013 abundance for a> 70% probability of Yellowstone cutthroat trout persistence at the performance metrics outlined in the Native Fish Conservation Plan. Lake trout removal will likely reduce lake trout abundance and result in Yellowstone cutthroat trout recovery if the amount of fishing effort exerted in 2013 is maintained for at least 15 years.

Effects of Introduced Lake Trout on Native Cutthroat Trout in Yellowstone Lake

Author : James R. Ruzycki
Publisher :
ISBN 13 :
Total Pages : 15 pages
Book Rating : 4.:/5 (13 download)

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Book Synopsis Effects of Introduced Lake Trout on Native Cutthroat Trout in Yellowstone Lake by : James R. Ruzycki

Download or read book Effects of Introduced Lake Trout on Native Cutthroat Trout in Yellowstone Lake written by James R. Ruzycki and published by . This book was released on 2003 with total page 15 pages. Available in PDF, EPUB and Kindle. Book excerpt: The establishment of a reproducing population of nonnative lake trout (Salvelinus namaycush) poses a serious threat to the integrity of the Yellowstone Lake ecosystem, particularly to the indigenous cutthroat trout (Oncorhynchus clarki bouvieri). We used standard fisheries techniques to quantify the population-level impact resulting from this introduction, while the U.S. National Park Service (NPS) developed a program to control their numbers. Lake trout diets, thermal history, growth, and size structure were incorporated into a bioenergetics model to estimate the predatory impact of introduced lake trout and to evaluate the effectiveness of the NPS lake trout control program. Population size structures were estimated from catches of fish in gill nets that were corrected for mesh size selectivity. Lake trout abundance was estimated using virtual population (cohort) analysis, and cutthroat trout abundance was estimated using hydroacoustics. Juvenile cutthroat trout were highly vulnerable to predation, and lake trout preyed on cutthroat trout that averaged 27?33% of their body length. Based on our model, an average piscivorous lake trout consumed 41 cutthroat trout each year. During 1996, the piscivorous lake trout population consumed an estimated 15 metric tons of cutthroat trout (129 000 fish) composing 14% of the vulnerable cutthroat trout production. The NPS removed nearly 15 000 lake trout from 1995 to 1999. Had these predators remained in Yellowstone Lake they would have consumed an estimated 23 metric tons of cutthroat trout (200 000 fish) during 1999 alone. If left unchecked, lake trout would clearly pose a serious threat to the long-term existence of the indigenous cutthroat trout. This analysis demonstrates the negative impact of an introduced predator in an ecologically isolated aquatic ecosystem.

Life History and Population Characteristics of Lake Trout Recently Discovered in Yellowstone Lake

Author : Lynn Robert Kaeding
Publisher :
ISBN 13 :
Total Pages : 22 pages
Book Rating : 4.:/5 (13 download)

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Book Synopsis Life History and Population Characteristics of Lake Trout Recently Discovered in Yellowstone Lake by : Lynn Robert Kaeding

Download or read book Life History and Population Characteristics of Lake Trout Recently Discovered in Yellowstone Lake written by Lynn Robert Kaeding and published by . This book was released on 1997 with total page 22 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Scientific Review Panel Evaluation of the National Park Service Lake Trout Suppression Program in Yellowstone Lake August 25?29, 2008

Download Scientific Review Panel Evaluation of the National Park Service Lake Trout Suppression Program in Yellowstone Lake August 25?29, 2008 PDF Online Free

Author : Robert E. Gresswell
Publisher :
ISBN 13 :
Total Pages : 17 pages
Book Rating : 4.:/5 (13 download)

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Book Synopsis Scientific Review Panel Evaluation of the National Park Service Lake Trout Suppression Program in Yellowstone Lake August 25?29, 2008 by : Robert E. Gresswell

Download or read book Scientific Review Panel Evaluation of the National Park Service Lake Trout Suppression Program in Yellowstone Lake August 25?29, 2008 written by Robert E. Gresswell and published by . This book was released on 2009 with total page 17 pages. Available in PDF, EPUB and Kindle. Book excerpt: Following the confirmation of the presence of nonnative lake trout (Salvelinus namaycush) in Yellowstone Lake during the summer of 1994, the National Park Service (NPS) launched a major suppression program to curtail potential negative consequences to the native Yellowstone cutthroat trout (Oncorhynchus clarki bouvieri) and the Yellowstone Lake ecosystem. In August 2008, the NPS convened a scientific review panel to evaluate the suppression program and provide direction for future suppression and recovery activities. The review panel met August 25?29, 2008 at Chico Hot Springs, Montana. This is a report of the findings and recommendations of the panel.

Yellowstone Lake Trout Creel Censuses, 1950-51 (Classic Reprint)

Author : Harvey L. Moore
Publisher : Forgotten Books
ISBN 13 : 9780332088822
Total Pages : 52 pages
Book Rating : 4.0/5 (888 download)

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Book Synopsis Yellowstone Lake Trout Creel Censuses, 1950-51 (Classic Reprint) by : Harvey L. Moore

Download or read book Yellowstone Lake Trout Creel Censuses, 1950-51 (Classic Reprint) written by Harvey L. Moore and published by Forgotten Books. This book was released on 2017-11-28 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt: Excerpt from Yellowstone Lake Trout Creel Censuses, 1950-51 Because of the problem of increased fishing pressure on Yellowstone Lake, the Fish and Wildlife Service, at the request of the National Park Service, initiated an extensive study to learn the effects of the ih crease, and to make recommendations, based on their findings, for a plan for a sustained yield fishery. This report is concerned with the results of the first two years of creel census studies. The study was initiated in 1950 and expanded in 1951 for collecting data for the determination of total annual fishing mortality. Data were collected in such a.manner that fishing effort and success could be analysed for relative annual and intro-seasonal changes, and for differences between.major fishing areas of the lake. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.

Changing Numbers of Spawning Cutthroat Trout in Tributary Streams of Yellowstone Lake and Estimates of Grizzly Bears Visitings Streams from DNA

Download Changing Numbers of Spawning Cutthroat Trout in Tributary Streams of Yellowstone Lake and Estimates of Grizzly Bears Visitings Streams from DNA PDF Online Free

Author : Mark A. Haroldson
Publisher :
ISBN 13 :
Total Pages : 14 pages
Book Rating : 4.:/5 (13 download)

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Book Synopsis Changing Numbers of Spawning Cutthroat Trout in Tributary Streams of Yellowstone Lake and Estimates of Grizzly Bears Visitings Streams from DNA by : Mark A. Haroldson

Download or read book Changing Numbers of Spawning Cutthroat Trout in Tributary Streams of Yellowstone Lake and Estimates of Grizzly Bears Visitings Streams from DNA written by Mark A. Haroldson and published by . This book was released on 2005 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt: Spawning Yellowstone cutthroat trout (Oncorhynchus clarki) provide a source of highly digestible energy for grizzly bears (Ursus arctos) that visit tributary streams to Yellowstone Lake during the spring and early summer. During 1985-87, research documented grizzly bears fishing on 61% of the 124 tributary streams to the lake. Using track measurements, it was estimated that a minimum of 44 grizzly bears fished those streams annually. During 1994, non-native lake trout (Salvelinus namaycush) were discovered in Yellowstone Lake. Lake trout are efficient predators and have the potential to reduce the native cutthroat population and negatively impact terrestrial predators that use cutthroat trout as a food resource. In 1997, we began sampling a subset of streams (n = 25) from areas of Yellowstone Lake surveyed during the previous study to determine if changes in spawner numbers or bear use had occurred. Comparisons of peak numbers and duration suggested a considerable decline between study periods in streams in the West Thumb area of the lake. The apparent decline may be due to predation by lake trout. Indices of bear use also declined on West Thumb area streams. We used DNA from hair collected near spawning streams to estimate the minimum number of bears visiting the vicinity of spawning streams. Seventy-four individual bears were identified from 429 hair samples. The annual number of individuals detected ranged from 15 in 1997 to 33 in 2000. Seventy percent of genotypes identified were represented by more than 1 sample, but only 31% of bears were documented more than 1 year of the study. Sixty-two (84%) bears were only documented in 1 segment of the lake, whereas 12 (16%) were found in 2-3 lake segments. Twenty-seven bears were identified from hair collected at multiple streams. One bear was identified on 6 streams in 2 segments of the lake and during 3 years of the study. We used encounter histories derived from DNA and the Jolly-Seber procedure in Program MARK to produce annual estimates of grizzly bears visiting streams. Approximately 68 grizzly bears visited the vicinity of cutthroat trout spawning streams annually. Thus, approximately 14-21% of grizzly bears in the Greater Yellowstone Ecosystem (GYE) may have used this threatened food resource annually. Yellowstone National Park (YNP) is attempting to control the lake trout population in Yellowstone Lake; our results underscore the importance of that effort to grizzly bears.

Informative Correlations Among Metrics of Yellowstone Lake Cutthroat Trout Caught by Two Quantitative Methods Across Three Recent Decades

Download Informative Correlations Among Metrics of Yellowstone Lake Cutthroat Trout Caught by Two Quantitative Methods Across Three Recent Decades PDF Online Free

Author : Lynn Robert Kaeding
Publisher :
ISBN 13 :
Total Pages : 5 pages
Book Rating : 4.:/5 (13 download)

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Book Synopsis Informative Correlations Among Metrics of Yellowstone Lake Cutthroat Trout Caught by Two Quantitative Methods Across Three Recent Decades by : Lynn Robert Kaeding

Download or read book Informative Correlations Among Metrics of Yellowstone Lake Cutthroat Trout Caught by Two Quantitative Methods Across Three Recent Decades written by Lynn Robert Kaeding and published by . This book was released on 2013 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Yellowstone Cutthroat Trout Oncorhynchus clarkii bouvieri (YCT) of Yellowstone Lake, in Yellowstone National Park, Wyoming, is an iteroparous fish and obligate stream spawner. The size and several other attributes of the annual YCT spawning run in one lake tributary, Clear Creek, have been periodically estimated for several decades. The trends in that run's metrics have been assumed to depict the trends in the lake's YCT population as a whole, although such associations had not been substantiated by statistical analyses. The present study revealed strong correlations between metrics of YCT in the run (years 1977-2007) and of "prespawner" YCT (i.e., mature fish whose excised gonads indicated that the fish would have spawned the next year) caught in gill nets set in various lake locations the preceding fall. Data for both capture methods also revealed a negative effect of spawning population density on YCT somatic growth, which is known to be positively associated with fecundity. This study showed that most metrics of YCT in the Clear Creek spawning run were indicative of those of prespawner YCT in Yellowstone Lake and aided the development of population models that are needed to determine the causal factors in the recent, three-decade population decline of YCT.

A Population Study of Yellowstone Blackspotted Trout (Salmo Clarkii Lewisi Girard)

Author : James Paisley Welsh
Publisher :
ISBN 13 :
Total Pages : 462 pages
Book Rating : 4.F/5 ( download)

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Book Synopsis A Population Study of Yellowstone Blackspotted Trout (Salmo Clarkii Lewisi Girard) by : James Paisley Welsh

Download or read book A Population Study of Yellowstone Blackspotted Trout (Salmo Clarkii Lewisi Girard) written by James Paisley Welsh and published by . This book was released on 1952 with total page 462 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Genetic Considerations for the Conservation and Management of Yellowstone Cutthroat Trout (Oncorhynchus Clarkii Bouvieri) in Yellowstone National Park

Download Genetic Considerations for the Conservation and Management of Yellowstone Cutthroat Trout (Oncorhynchus Clarkii Bouvieri) in Yellowstone National Park PDF Online Free

Author : David Joel Janetski
Publisher :
ISBN 13 :
Total Pages : 124 pages
Book Rating : 4.:/5 (854 download)

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Book Synopsis Genetic Considerations for the Conservation and Management of Yellowstone Cutthroat Trout (Oncorhynchus Clarkii Bouvieri) in Yellowstone National Park by : David Joel Janetski

Download or read book Genetic Considerations for the Conservation and Management of Yellowstone Cutthroat Trout (Oncorhynchus Clarkii Bouvieri) in Yellowstone National Park written by David Joel Janetski and published by . This book was released on 2006 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt: A key component to conservation is an accurate understanding of genetic subdivision within a species. Despite their ecological and economic importance, relatively little is understood about the genetic structuring of Yellowstone cutthroat trout in Yellowstone National Park. Here, we use traditional (Fst, Rst, Nm, and AMOVA) and modern (Bayesian assignment tests, coalescent theory, and nested clade analysis) analytical approaches to describe the population genetic subdivision of cutthroat trout spawning populations in Yellowstone Lake and to identify genetically distinct population segments throughout Yellowstone National Park. Evidence for restricted gene flow between spawning populations within Yellowstone Lake was detected using nested clade analysis. This is the first molecular evidence for restricted gene flow between spawning populations in Yellowstone Lake. In contrast, traditional methods such as Fst and Rst as well as the Bayesian clustering program STRUCTURE v2.0 failed to detect evidence for restricted gene flow. Across our sampling range within Yellowstone National Park, eleven genetically distinct cutthroat trout population segments were detected. These showed a general pattern of small, isolated populations with low genetic diversity in headwater streams and wide-spread, genetically diverse populations in higher-order rivers. We recommend populations be managed to maintain current levels of genetic diversity and gene flow. Based on the recent decline of and distinct morphological, behavioral, and genetic nature of cutthroat trout in Yellowstone Lake, we recommend the Yellowstone Lake spawning populations collectively be recognized as an evolutionarily significant unit.