Indirect Effects Of Bioinvasions In Yellowstone Lake The Response Of River Otters To Declines In Native Cutthroat Trout

Download Indirect Effects Of Bioinvasions In Yellowstone Lake The Response Of River Otters To Declines In Native Cutthroat Trout full books in PDF, epub, and Kindle. Read online Indirect Effects Of Bioinvasions In Yellowstone Lake The Response Of River Otters To Declines In Native Cutthroat Trout ebook anywhere anytime directly on your device. Fast Download speed and no annoying ads. We cannot guarantee that every ebooks is available!

Indirect Effects of Bioinvasions in Yellowstone Lake: The Response of River Otters to Declines in Native Cutthroat Trout

Author : Jamie R. Crait
Publisher :
ISBN 13 :
Total Pages : 10 pages
Book Rating : 4.:/5 (13 download)

DOWNLOAD NOW!

Book Synopsis Indirect Effects of Bioinvasions in Yellowstone Lake: The Response of River Otters to Declines in Native Cutthroat Trout by : Jamie R. Crait

Download or read book Indirect Effects of Bioinvasions in Yellowstone Lake: The Response of River Otters to Declines in Native Cutthroat Trout written by Jamie R. Crait and published by . This book was released on 2015 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nonnative species threaten ecosystems throughout the world ? including protected reserves. In Yellowstone National Park, river otters Lontra canadensis depend on native cutthroat trout as prey. However, nonnative lake trout and whirling disease have significantly reduced the abundance of these native fish in the park's largest body of water, Yellowstone Lake. We studied the demographic and behavioral responses of otters to declining cutthroat trout on Yellowstone Lake and its tributaries. From 2002-2008, we monitored otter activity at latrine (scent-marking) sites, collected scat for prey identification, and used individual genotypes from scat and hair samples to evaluate survival and abundance with capture?recapture methods. Otter activity at latrines decreased with declines in cutthroat trout, and the prevalence of these fish in otter scat declined from 73% to 53%. Cutthroat trout numbers were the best predictor of temporal variation in apparent survival, and mean annual survival for otters was low (0.72). The density of otters in our study area (1 otter per 13.4 km of shoreline) was also low, and evidence of a recent genetic bottleneck suggests that otter abundance might have declined prior to our study. River otters in and around Yellowstone Lake appear to be responding to reductions in cutthroat trout via changes in distribution, diet, and possibly survival and abundance. Our results provide a baseline estimate for monitoring the broader outcome of management efforts to conserve native cutthroat trout and emphasize the indirect ecosystem consequences of invasive species.

The Impact of Nonnative Species on River Otters and Aquatic-terrestrial Linkages in Yellowstone National Park

Author : Jamie R. Crait
Publisher :
ISBN 13 : 9781303106767
Total Pages : 178 pages
Book Rating : 4.1/5 (67 download)

DOWNLOAD NOW!

Book Synopsis The Impact of Nonnative Species on River Otters and Aquatic-terrestrial Linkages in Yellowstone National Park by : Jamie R. Crait

Download or read book The Impact of Nonnative Species on River Otters and Aquatic-terrestrial Linkages in Yellowstone National Park written by Jamie R. Crait and published by . This book was released on 2013 with total page 178 pages. Available in PDF, EPUB and Kindle. Book excerpt: River otters (Lontra canadensis) in Yellowstone Lake, Yellowstone National Park, depend on native cutthroat trout (Oncorhynchus clarki bouvieri) as prey, especially during summer when the fish migrate from the lake into its tributary streams to spawn. As part of their social behavior, otters deposit excreta at latrine (scent-marking) sites along these spawning streams and fertilize riparian plants with aquatically-derived nutrients such as nitrogen (N). Over the last two decades, however, nonnative lake trout trout (Salvelinus namaycush ) and whirling disease (caused by the parasite Myxobolus cerebralis), have contributed to a dramatic decline in the lake's cutthroat trout population. Declines in cutthroat trout could reduce the abundance and distribution of otters, and sever the nutrient link they provide. This dissertation describes aspects of the biology of river otters in Yellowstone Lake in the context of these changes to the lake's food web. This dissertation is presented in four journal-formatted chapters. Chapter 1 compares the hematology of high elevation Yellowstone otters with a sea level population. Comparisons of oxygen dissociation curves revealed no significant difference in hemoglobin-oxygen binding affinity between the two populations. Instead, high elevation otters had greater hemoglobin concentrations than their sea level conspecifics. Yellowstone otters displayed higher levels of the vasodilator nitric oxide, and half the concentration of the serum protein albumin, possibly to compensate for increased blood viscosity. Theoretical aerobic dive limits were similar between high elevation and sea level otters due to the lower availability of oxygen at altitude. Chapter 2 presents the first estimates of population size and survival for river otters in Yellowstone National Park. Although the cutthroat trout population continued to decline during the study, there was no significant change in otter population size. However, overall densities (1 otter/9.91 km of shoreline) were lower than reported for most river otter populations, and evidence of a recent genetic bottleneck suggested the population may have already declined by the onset of the study. Annual survival for otters was 0.67 and correlated with cutthroat trout abundance in some models. Otters primarily responded to reductions in cutthroat trout via behavioral shifts in their spatial distribution and prey consumption. Activity at latrine sites decreased with declines in cutthroat trout on several tributary streams. Cutthroat trout remained the dominant prey item in otter scats throughout the study, but showed a declining trend from a frequency of occurrence of 73% in 2003 to 54% in 2008. Chapter 3 documents the effects of otter-derived N fertilization on trees at latrine sites. Stable N isotope (15 N) values were higher in needles of Engelmann spruce (Picea engelmannii) and lodgepole pine (Pinus contorta) on otter latrines than at reference sites. However, tree growth was greater on reference sites. No relationship existed between cutthroat trout abundance and tree ring 15 N, precluding the ability to detect whether the trout-otter-excreta link has changed with the cutthroat trout population. Chapter 4 is a note on seasonal breeding in Yellowstone otters. Although river otters in temperate regions typically breed in March and April, Yellowstone otters showed evidence of late seasonal breeding in June. This observation suggests otters in Yellowstone Lake have a relatively long breeding season, or their breeding schedule is delayed so that energetically-demanding lactation coincides with spawning runs of Yellowstone cutthroat trout. (Abstract shortened by UMI.)

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)

DOWNLOAD NOW!

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.

Ecological Consequences of Invasive Lake Trout on River Otters in Yellowstone National Park

Author : William Ralph Wengeler
Publisher :
ISBN 13 :
Total Pages : 10 pages
Book Rating : 4.:/5 (13 download)

DOWNLOAD NOW!

Book Synopsis Ecological Consequences of Invasive Lake Trout on River Otters in Yellowstone National Park by : William Ralph Wengeler

Download or read book Ecological Consequences of Invasive Lake Trout on River Otters in Yellowstone National Park written by William Ralph Wengeler and published by . This book was released on 2010 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt: The introduction of lake trout (Salvelinus namaycush) to Yellowstone Lake in Yellowstone National Park has contributed to a significant decline in the endangered Yellowstone cutthroat trout (Oncorhynchus clarki bouvieri), leading to concern over the persistence of this subspecies but also to piscivorous predators in this community. We assessed the impact of lake trout on a key piscivore, the river otter (Lontra canadensis) in two lakes in Yellowstone National Park. Yellowstone Lake continues to support a native cutthroat trout population, although the recent introduction of lake trout has dramatically impacted the cutthroat trout population. Nearby Lewis Lake has an entirely introduced fish fauna of lake trout, brown trout (Salmo trutta), and Utah chub (Gilia atraria) but lacks cutthroat trout. Analysis of otter scat from Yellowstone Lake implicated trout (lake or cutthroat trout) as a major prey item (57% of scat), whereas stable isotopes identified longnose suckers (Catostomus catostomus) as the primary prey there (58% of diet). By contrast, scat from Lewis Lake implicated minnows, presumably Utah chub, as the primary prey for otters occupying that lake (86%), while stable isotopes implicated brown trout (64%) over both lake trout and Utah chub (36% combined). Our data establish the importance of alternative prey to otters and suggest that lake trout-induced reductions in cutthroat trout may not be catastrophic for otter populations here. These data do not necessarily exonerate lake trout, as their impact on other species, most notably grizzly bears (Ursus arctos) and piscivorous birds, has been documented to be substantial, and further data on the nutritional value of alternate prey are required to confirm or refute a working hypothesis that otter populations will continue to thrive in the face of the lake trout invasion.

Socio-economic and Eco-biological Dimensions in Resource use and Conservation

Author : Niranjan Roy
Publisher : Springer Nature
ISBN 13 : 303032463X
Total Pages : 553 pages
Book Rating : 4.0/5 (33 download)

DOWNLOAD NOW!

Book Synopsis Socio-economic and Eco-biological Dimensions in Resource use and Conservation by : Niranjan Roy

Download or read book Socio-economic and Eco-biological Dimensions in Resource use and Conservation written by Niranjan Roy and published by Springer Nature. This book was released on 2020-01-27 with total page 553 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents the outcomes of the 2017 national workshop and international conference organized by CEENR of ISEC, Bengaluru and Assam University Silchar. Addressing the threats to biodiversity and sustainable development resulting from the impacts of human induced pressures on ecosystems and global-warming-driven climate change is a major challenge. It requires increased knowledge and an enhanced information base in order to devise local policies to improve the adaptive capacity of vulnerable socio-ecological systems in developing countries. In this context, the book presents research that has the potential to benefit the environment and empower communities. It appeals to researchers investigating diverse aspects of socio-ecological-biological systems to create strategies for resource use, conservation and management to ensure sustainability.

Feeding Habits of Yellowstone River Otters on Two Lakes

Author : William Ralph Wengeler
Publisher :
ISBN 13 :
Total Pages : 128 pages
Book Rating : 4.:/5 (79 download)

DOWNLOAD NOW!

Book Synopsis Feeding Habits of Yellowstone River Otters on Two Lakes by : William Ralph Wengeler

Download or read book Feeding Habits of Yellowstone River Otters on Two Lakes written by William Ralph Wengeler and published by . This book was released on 2008 with total page 128 pages. Available in PDF, EPUB and Kindle. Book excerpt: "The introduction of exotic lake trout (Salvelinus namaycush) to Yellowstone Lake in Yellowstone National Park has contributed to a significant decline in the heretofore healthy population of Yellowstone cutthroat trout (Oncorhynchus clarki bouvieri). There is great concern not only regarding the persistence of this genetically pure cutthroat subspecies, but also for the potential impacts their disappearance will have on the fish-eating predators of Yellowstone Lake and the surrounding community. Nearby Lewis Lake has no cutthroat trout, but is home to a well-established population of non-native lake trout, brown trout (Salmo trutta), and Utah chub (Gila atraria). We examined the contents of 179 river otter (Lontra canadensis) scats collected along the shores of Yellowstone (n=101) and Lewis Lakes (n=78) in Yellowstone National Park to compare otter dietary habits, especially with regard to the mustelid's utilization of native vs. non-native fish species. We also assessed diets using stable isotopes analysis ... on otters and represenatative prey from both lakes. In addition, we analyzed the isotopic signatures of fur taken from Yellowstone Lake otter specimens collected in the early part of the 20th century before exotic trout were introduced. Fecal analysis indicated that trout were consumed much more frequently by contemporary Yellowstone Lake otters (57% annually) than by otters occupying Lewis Lake (12% annually). The predominant fish found in Lewis Lake otter feces were minnows, presumably Utah chub. Stable isotopes analysis, however, identified longnose suckers (Catostomus catostomus) as the primary fish prey for Yellowstone Lake otters (56% contribution to otter diet), while indicating that otters there are generally preying on neither cutthroat trout nor introduced lake trout. Analysis of stable isotopes also indicated that contemporary Yellowstone Lake otters forage at a lower trophic level ... than their historic counterparts ... Isotopic data from Lewis Lake revealed that brown trout (60% contribution to otter diet) contribute more to otter diets there than local lake trout and Utah chub together (40% combined contribution). This study establishes the importance of alternative prey species to otters foraging on both lakes and supplements the growing body of research demonstrating that lake trout will not constitute a major food source for Yellowstone river otters."--Abstract.

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)

DOWNLOAD NOW!

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.

Carcass Deposition to Suppress Invasive Lake Trout Causes Differential Mortality of Two Common Benthic Invertebrates in Yellowstone Lake

Download Carcass Deposition to Suppress Invasive Lake Trout Causes Differential Mortality of Two Common Benthic Invertebrates in Yellowstone Lake PDF Online Free

Author : Michelle A. Briggs
Publisher :
ISBN 13 :
Total Pages : 11 pages
Book Rating : 4.:/5 (13 download)

DOWNLOAD NOW!

Book Synopsis Carcass Deposition to Suppress Invasive Lake Trout Causes Differential Mortality of Two Common Benthic Invertebrates in Yellowstone Lake by : Michelle A. Briggs

Download or read book Carcass Deposition to Suppress Invasive Lake Trout Causes Differential Mortality of Two Common Benthic Invertebrates in Yellowstone Lake written by Michelle A. Briggs and published by . This book was released on 2021 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: Invasive species require management to mitigate their harmful effects on native biodiversity and ecosystem processes. However, such management can also have negative, unintended consequences on non-target taxa, ecosystem processes, and food web dynamics. In Yellowstone Lake, invasive lake trout (Salvelinus namaycush) have caused a decline in the native Yellowstone cutthroat trout (Oncorhynchus clarkii bouvieri) population. To suppress the invader, lake trout carcasses are deposited on the species? spawning sites, causing embryo mortality by reducing dissolved oxygen as they decay. The non-target effects of carcass deposition are unknown, but benthic invertebrates may be sensitive to reductions in dissolved oxygen. Benthic invertebrate taxa have varying hypoxia tolerances; caddisflies of the family Limnephilidae are hypoxia sensitive whereas the amphipods Gammarus lacustris and Hyalella azteca are hypoxia tolerant. Both taxa are widespread and abundant in Yellowstone Lake and comprise a large proportion of fish diets, and changes in their abundances could therefore alter food web dynamics. We conducted an in situ experiment to determine if carcass deposition causes mortality in these two benthic invertebrate taxa. The probability of mortality for caddisflies was 3.15 times higher in carcass treatments compared to controls, while amphipod mortality did not change in response to carcass treatment. Amphipods, which contribute most significantly to fish diets, are unlikely to be reduced in response to carcass deposition, which is confined to a small fraction of the lake where lake trout spawn, limiting the possibility for lake-wide effects. We conclude that carcass deposition is unlikely to alter the availability of invertebrates as a food source for fish in Yellowstone Lake.

Mortality Studies on Cutthroat Trout in Yellowstone Lake [by] Orville P. Ball and Oliver B. Cope

Author : Orville P. Ball
Publisher :
ISBN 13 :
Total Pages : 72 pages
Book Rating : 4.3/5 (91 download)

DOWNLOAD NOW!

Book Synopsis Mortality Studies on Cutthroat Trout in Yellowstone Lake [by] Orville P. Ball and Oliver B. Cope by : Orville P. Ball

Download or read book Mortality Studies on Cutthroat Trout in Yellowstone Lake [by] Orville P. Ball and Oliver B. Cope written by Orville P. Ball and published by . This book was released on 1961 with total page 72 pages. Available in PDF, EPUB and Kindle. Book excerpt: In a study of the Yellowstone Lake cutthroat trout, Salmo clarki lewisi, by the U.S. Fish and Wildlife Service, effects of environment on mortality of eggs, immature fish, spawners, and postspawners were measured for various components of the population in Yellowstone Lake (Wyoming). Five methods for estimating mortality of adults on spawning runs are described, with counting and tagging as the principal procedures. Of the total number of eggs deposited in the gravel, 60 to 75 percent died before hatching, and 99.6 percent had died by the time the fingerlings enetered Yellowstone Lake. In Arnica Creek runs, 48.6 percent died in the stream, 40.2 died later in the lake of natural causes, 7.6 were taken by fishermen, and 3.6 percent were alive 2 years later. The white pelican is a serious predator on cutthroat trout in Yellowstone Lake. From 1949 to 1953 fishermen caught 11.6 percent of the catchable trout available to them. Migrations of adult fish in Yellowstone Lake were traced through tagging.

River Otters, Cutthroat Trout, and Their Future in Yellowstone National Park

Author : Jamie R. Crait
Publisher :
ISBN 13 :
Total Pages : 3 pages
Book Rating : 4.:/5 (13 download)

DOWNLOAD NOW!

Book Synopsis River Otters, Cutthroat Trout, and Their Future in Yellowstone National Park by : Jamie R. Crait

Download or read book River Otters, Cutthroat Trout, and Their Future in Yellowstone National Park written by Jamie R. Crait and published by . This book was released on 2002 with total page 3 pages. Available in PDF, EPUB and Kindle. Book excerpt:

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)

DOWNLOAD NOW!

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.

Migrate, Mutate, Or Die

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

DOWNLOAD NOW!

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.

Ecosystem Consequences of Declining Yellowstone Cutthroat Trout in Yellowstone Lake and Spawning Streams

Author : Lusha M. Tronstad
Publisher :
ISBN 13 : 9780549795315
Total Pages : 155 pages
Book Rating : 4.7/5 (953 download)

DOWNLOAD NOW!

Book Synopsis Ecosystem Consequences of Declining Yellowstone Cutthroat Trout in Yellowstone Lake and Spawning Streams by : Lusha M. Tronstad

Download or read book Ecosystem Consequences of Declining Yellowstone Cutthroat Trout in Yellowstone Lake and Spawning Streams written by Lusha M. Tronstad and published by . This book was released on 2008 with total page 155 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Non-Target Effects of a Novel Invasive Species Management Strategy

Author : Michelle Anne Briggs
Publisher :
ISBN 13 :
Total Pages : 102 pages
Book Rating : 4.:/5 (13 download)

DOWNLOAD NOW!

Book Synopsis Non-Target Effects of a Novel Invasive Species Management Strategy by : Michelle Anne Briggs

Download or read book Non-Target Effects of a Novel Invasive Species Management Strategy written by Michelle Anne Briggs and published by . This book was released on 2020 with total page 102 pages. Available in PDF, EPUB and Kindle. Book excerpt: Invasive species threaten native biodiversity and ecosystem function, and suppression is often required to reduce these effects. However, invasive species management actions can cause harmful, unintended consequences for non-target taxa. In Yellowstone Lake, Wyoming, invasive lake trout (Salvelinus namaycush) have reduced abundance of the native Yellowstone cutthroat trout (Oncorhynchus clarkii bouvieri), decreasing availability of an important food source for aquatic and terrestrial predators. Gillnets are used to suppress adult lake trout, and the lake trout carcasses are then deposited onto spawning sites in the littoral zone to cause embryo mortality by reducing dissolved oxygen concentrations as they decay. However, this management action may have non-target effects on organisms in the lake, including benthic invertebrates, which comprise a large portion of native trout diets. Some taxa of invertebrates may benefit from the addition of nutrients to the littoral zone, while other taxa may experience mortality in response to low dissolved oxygen conditions caused by carcass decay. We conducted two field experiments to understand how carcass treatment affects benthic invertebrates in Yellowstone Lake. First, we conducted an in situ experiment with individual invertebrates housed in small chambers covered by carcasses to determine if carcass treatment causes mortality of hypoxia-tolerant amphipods and hypoxia-sensitive caddisflies. We found that carcass treatment caused increased mortality in caddisflies but not amphipods. Second, we conducted a field experiment to investigate how carcass treatment affects invertebrate communities when applied at entire spawning sites. We also compared invertebrate communities at cobble-dominated lake trout spawning sites to macrophyte-dominated sites to determine if carcass treatment could alter food web dynamics at a lake-wide scale. We found that carcass treatment causes non-target effects on benthic invertebrates, specifically reducing immobile taxa, hypoxia-sensitive taxa, and Chironomidae, and altering community structure. Areas dominated by macrophytes had more abundant and larger invertebrates than spawning sites. Due to the small spatial extent of spawning sites and the higher abundance of invertebrates at other habitats in the lake, we conclude carcass treatment can have localized non-target effects at a local scale but is unlikely to alter food-web dynamics at a lake-wide scale.

Contrasting Past and Current Numbers of Bears Visiting Yellowstone Cutthroat Trout Streams

Author : Justin Everette Teisberg
Publisher :
ISBN 13 :
Total Pages : 10 pages
Book Rating : 4.:/5 (13 download)

DOWNLOAD NOW!

Book Synopsis Contrasting Past and Current Numbers of Bears Visiting Yellowstone Cutthroat Trout Streams by : Justin Everette Teisberg

Download or read book Contrasting Past and Current Numbers of Bears Visiting Yellowstone Cutthroat Trout Streams written by Justin Everette Teisberg and published by . This book was released on 2014 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt: Spawning cutthroat trout (Oncorhynchus clarkii bouvieri) were historically abundant within tributary streams of Yellowstone Lake within Yellowstone National Park and were a highly digestible source of energy and protein for Yellowstone's grizzly bears (Ursus arctos) and black bears (U. americanus). The cutthroat trout population has subsequently declined since the introduction of non-native lake trout (Salvelinus namaycush), and in response to effects of drought and whirling disease (Myxobolus cerebralis). The trout population, duration of spawning runs, and indices of bear use of spawning streams had declined in some regions of the lake by 1997?2000. We initiated a 3-year study in 2007 to assess whether numbers of spawning fish, black bears, and grizzly bears within and alongside stream corridors had changed since 1997?2000. We estimated numbers of grizzly bears and black bears by first compiling encounter histories of individual bears visiting 48 hair-snag sites along 35 historically fished streams. We analyzed DNA encounter histories with Pradel-recruitment and Jolly-Seber (POPAN) capture-mark-recapture models. When compared to 1997?2000, the current number of spawning cutthroat trout per stream and the number of streams with cutthroat trout has decreased. We estimated that 48 (95% CI?=?42?56) male and 23 (95% CI?=?21?27) female grizzly bears visited the historically fished tributary streams during our study. In any 1-year, 46 to 59 independent grizzly bears (8?10% of estimated Greater Yellowstone Ecosystem population) visited these streams. When compared with estimates from the 1997 to 2000 study and adjusted for equal effort, the number of grizzly bears using the stream corridors decreased by 63%. Additionally, the number of black bears decreased between 64% and 84%. We also document an increased proportion of bears of both species visiting front-country (i.e., near human development) streams. With the recovery of cutthroat trout, we suggest bears that still reside within the Lake basin will readily use this high-quality food resource.

Introduced Lake Trout Alter Nitrogen Cycling Beyond Yellowstone Lake

Author : Lusha Marguerite Tronstad
Publisher :
ISBN 13 :
Total Pages : 24 pages
Book Rating : 4.:/5 (13 download)

DOWNLOAD NOW!

Book Synopsis Introduced Lake Trout Alter Nitrogen Cycling Beyond Yellowstone Lake by : Lusha Marguerite Tronstad

Download or read book Introduced Lake Trout Alter Nitrogen Cycling Beyond Yellowstone Lake written by Lusha Marguerite Tronstad and published by . This book was released on 2015 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt: Introduced predators can have large effects on the ecosystem in which they were introduced, but how much these effects extend to other ecosystems beyond the invaded one is less known. We compared how lake trout (Salvelinus namaycush) affected nutrient cycling in an invaded and adjacent ecosystem in Yellowstone National Park, Wyoming, USA. Introduced lake trout in Yellowstone Lake caused the native Yellowstone cutthroat trout (Oncoryhynchus clarkii bouvieri) population to decline. Native cutthroat trout are a dominant animal in the lake and may alter nutrient cycling in both Yellowstone Lake where they reside and in tributary streams used for spawning. We estimated changes in nutrient transport and nutrient uptake in both Yellowstone Lake and Clear Creek, a spawning stream, before and after the invasion of lake trout. Annual area-specific excretion fluxes from cutthroat trout were nine times higher in Clear Creek compared to Yellowstone Lake when cutthroat trout were abundant. However, fluxes within the lake and stream were similar after cutthroat trout declined. In Yellowstone Lake, zooplankton excretion supplied 86% of ammonium (NH4+) that was taken up, but cutthroat trout only supplied 0.3% after the introduction of lake trout. Conversely, NH4+ excreted by cutthroat trout was likely a major flux in Clear Creek, because NH4+ fluxes from cutthroat trout exceeded watershed export of NH4+ in years when 3000 cutthroat trout spawned. Furthermore, NH4+ excretion fluxes from spawning cutthroat trout in Clear Creek supplied up to 6.1% of the NH4+ demanded by microbes after the introduction of lake trout. However, based on modeled past NH4+ uptake, we estimated that up to 60% of NH4+ excreted by spawning cutthroat trout may have been taken up by stream microbes when cutthroat trout were abundant. Therefore, transported NH4+ from spawning cutthroat trout was likely an integral part of N cycling in tributary streams in the past. By comparing the effects of declining cutthroat trout on two ecosystems, we show that lake trout had a larger effect on N cycling within an adjacent stream ecosystem than the invaded lake ecosystem itself, because the migratory behavior of cutthroat trout concentrated them in spawning streams increasing their effect.

Predicting Year-class Abundance of Yellowstone Lake Cutthroat Trout

Author : Ross V. Bulkley
Publisher :
ISBN 13 :
Total Pages : 32 pages
Book Rating : 4.3/5 (91 download)

DOWNLOAD NOW!

Book Synopsis Predicting Year-class Abundance of Yellowstone Lake Cutthroat Trout by : Ross V. Bulkley

Download or read book Predicting Year-class Abundance of Yellowstone Lake Cutthroat Trout written by Ross V. Bulkley and published by . This book was released on 1962 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fluctuations in strength of year classes from 1945 to 1956 of Yellowstone Lake cutthroat from Pelican and Chipmunk Creeks are compared with the parental stock and several climatically influenced factors of the environment. Variations in year-class strength in the two tributaries were highly correlated with fluctuations in lake water levels. Strong year classes occurred in yeas of low water. Female spawner escapement, timing of the runs, and summer air temperatures were not significant factors. A formula based on water levels is presented for predicting year-class strength in Pelican Creek and in the Fishing Bridge area fishery. Stocking of fry in years of high water is suggested as a means of supplementing natural production. A method of forecasting lake water levels several months in advance of their occurrence is discussed.