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Full-Text Articles in Ecology and Evolutionary Biology

Fisheries Management Paper No.273 - Blue Swimmer Crab Resource Of The Peel-Harvey Estuary Harvest Strategy, 2015-2020. Version 1.0, Department Of Fisheries, Western Australia Apr 2015

Fisheries Management Paper No.273 - Blue Swimmer Crab Resource Of The Peel-Harvey Estuary Harvest Strategy, 2015-2020. Version 1.0, Department Of Fisheries, Western Australia

Fisheries Management Papers

Harvest strategies for aquatic resources managed by the Western Australian Department of Fisheries (the Department) are formal documents prepared to support the decision-making processes required to ensure the management of these resources are consistent with the principles of Ecologically Sustainable Development (ESD). The objectives of ESD are reflected in the objects of the Fish Resources Management Act 1994 (FRMA), Section 3, and the draft Aquatic Resources Management Bill 2013 (ARMB), Clause 9, which will replace the FRMA once enacted.

The publication of these strategies is intended to make the decision-making considerations and processes for the management of specified aquatic resources …


Ocean Food Systems, Barry A. Costa-Pierce Mar 2015

Ocean Food Systems, Barry A. Costa-Pierce

Marine Sciences Faculty Presentations

Presentation given during session on Food Justice, where Barton Seaver, Director of the Healthy and Sustainable Food Program in the T.H. Chan School of Public Health at Harvard, described a great nutrition and health crisis in America perpetuated by groups demarketing seafood and promoting meat in the American diet. Seaver noted that Americans consume about 167 lbs. of meat a year and only 14 lbs. of seafood, leading to connected public health and environmental crises, heart disease, and obesity.

According to presenter Barry Costa-Pierce:

Seafood systems in the USA are our most insane foods; America imports nearly every seafood we …


Growth Of A Deep-Water, Predatory Fish Is Influenced By The Productivity Of A Boundary Current System, Hoang Minh Nguyen, Adam N. Rountrey, Jessica J. Meeuwig, Peter G. Coulson, Ming Feng, Stephen J. Newman, Anya M. Waite, Corey B. Wakefield, Mark G. Meekan Mar 2015

Growth Of A Deep-Water, Predatory Fish Is Influenced By The Productivity Of A Boundary Current System, Hoang Minh Nguyen, Adam N. Rountrey, Jessica J. Meeuwig, Peter G. Coulson, Ming Feng, Stephen J. Newman, Anya M. Waite, Corey B. Wakefield, Mark G. Meekan

Fisheries Research Articles

The effects of climate change on predatory fishes in deep shelf areas are difficult to predict because complex processes may govern food availability and temperature at depth. We characterised the net impact of recent environmental changes on hapuku (Polyprion oxygeneios), an apex predator found in continental slope habitats (>200 m depth) by using dendrochronology techniques to develop a multi-decadal record of growth from otoliths. Fish were sampled off temperate south-western Australia, a region strongly influenced by the Leeuwin Current, a poleward-flowing, eastern boundary current. The common variance among individual growth records was relatively low (3.4%), but the …


Shifts In Attack Behavior Of An Important Kelp Forest Predator Within Marine Reserves, J. S. Berriman, M. C. Kay, D. C. Reed, A. Rassweiler, D. A. Goldstein, William G. Wright Mar 2015

Shifts In Attack Behavior Of An Important Kelp Forest Predator Within Marine Reserves, J. S. Berriman, M. C. Kay, D. C. Reed, A. Rassweiler, D. A. Goldstein, William G. Wright

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Marine reserves have become increasingly valuable tools with which to manage ecosystems. These reserves consistently restore populations of top predators, often reducing availability of their favored prey. We hypothesized that such prey reduction in reserves causes protected predators to alter their attack behavior to include less palatable prey, potentially amplifying top-down effects on community structure. To test this hypothesis, we presented the relatively unpalatable sea hare Aplysia californica to freely foraging spiny lobsters Panulirus interruptus in 4 marine no-take reserves, each paired with an adjacent fished area. We found that lobsters only attacked sea hares inside reserves, where lobster density …


Population Level Responses To Direct Application Liming In Gyrinophilus Porphyriticus, Shelby Renea Timm Jan 2015

Population Level Responses To Direct Application Liming In Gyrinophilus Porphyriticus, Shelby Renea Timm

Theses, Dissertations and Capstones

Direct application liming (DAL) has been used to neutralize acidified streams to restore aquatic biota. This mitigation technique has been used globally for decades, yet little data exist on its effects on amphibian populations. My study investigated the effects of liming on amphibians by measuring variability in life histories of larval Gyrinophilus porphyriticus. I collected larvae from six streams in the Monongahela National Forest, West Virginia. I examined the effects of DAL on age structure, and I failed to detect a treatment effect. I used ANCOVAs to examine differences in body condition, body size, and gape size. I observed that …


Monitoring The Land Cover Change In The Historic Range Of Cambarus Veteranus In West Virginia Using A 1973-2013 Landsat Time Series, Emma Martha Arneson Jan 2015

Monitoring The Land Cover Change In The Historic Range Of Cambarus Veteranus In West Virginia Using A 1973-2013 Landsat Time Series, Emma Martha Arneson

Theses, Dissertations and Capstones

The crayfish Cambarus veteranus is near extinction in its historic range of the Upper Guyandotte River watershed. The biggest threats to C. veteranus are mining and road construction. Mining has been a continuous activity in the southern coalfields where the crayfish has historically been found, yet little is known about how much land cover change the practice has done to the region. Crayfish act as important organisms within aquatic ecosystems and without them, those systems are often degraded. Quantifying the change in land cover is important to understanding threats to C. veteranus for future protection of the crayfish and its …


Abiotic Habitat Preferences Of Age-0 Paddlefish In Lake Sakakawea, North Dakota During Late Summer, Derek Dufault Jan 2015

Abiotic Habitat Preferences Of Age-0 Paddlefish In Lake Sakakawea, North Dakota During Late Summer, Derek Dufault

Journal of Earth and Life Science

Since the early 1990’s, surface visual counts along transects have been conducted annually, allowing for estimates of relative abundance and year-class strength of age-0 paddlefish Polyodon spathula on the upper portions of Lake Sakakawea, North Dakota. This study focuses on the annual visual surface count data collected over an eleven year period from 2004-2014. More specifically it focuses on abiotic habitat factors (Secchi depth, water depth, and water temperature) and how they relate to age-0 paddlefish locations in late summer. Understanding habitat use during early life stages is imperative, yet to date, there is very limited knowledge available regarding the …


Influence Of Depth And Retrieval Speed On Yellow Perch Barotrauma Recovery Time In Winter, Bradley J. Klingsheim Jan 2015

Influence Of Depth And Retrieval Speed On Yellow Perch Barotrauma Recovery Time In Winter, Bradley J. Klingsheim

Journal of Earth and Life Science

Physoclistous fish are often affected by barotrauma because the swim bladder is not connected to the esophagus. Barotrauma is increasingly being used in assessing mortality in fish brought from deep water. Barotrauma is the physical damage that occurs because of the over inflation of the gas bladder resulting from a rapid decrease in ambient pressure. The two important factors influencing barotrauma effects are water depth and decompression. In this study, two experiments were conducted on yellow perch (Perca flavescens) at three depth locations on Grace Lake, Bemidji, Minnesota. Fish were measured for barotrauma recovery time (s) following capture by hook …


Life-History Aspects Of Moxostoma Cervinum (Blacktip Jumprock) In The Roanoke River, Virginia, Dezarai A. Thompson, John S. Bentley, Steven L. Powers Jan 2015

Life-History Aspects Of Moxostoma Cervinum (Blacktip Jumprock) In The Roanoke River, Virginia, Dezarai A. Thompson, John S. Bentley, Steven L. Powers

Virginia Journal of Science

Life-history aspects of Moxostoma cervinum(Blacktip Jumprock) were identified using specimens from recent collections and the Roanoke College Ichthyological Collection. The largest specimen examined was a female 161.27 mm SL and 66 months of age. Spawning appears to occur in May, with a mean of 2477.6 oocytes (SD = 2825.3) up to 1.54 mm diameter in gravid females. Sexual maturity appears to occur by 1-2 years of age in males and 2-3 years of age in females. Male to female ratio was not significantly different from 1:1. Chironomidae composed the bulk of the diet; while detritus, Trichoptera, Ephemeroptera, and Acari …


Behavioral Response Of Pacific Lamprey (Entosphenus Tridentatus) To Predator Odors, Laurie L. Porter Jan 2015

Behavioral Response Of Pacific Lamprey (Entosphenus Tridentatus) To Predator Odors, Laurie L. Porter

All Master's Theses

Pacific lamprey (Entosphenus tridentatus), a species facing serious threats to their existence, experience a number of challenges in reaching their desired spawning grounds during the adult migratory phase, and predators are suspected to be one of these challenges. Understanding if Pacific lamprey respond to predator odorants may provide a management tool for use in conjunction with attractants in guiding lamprey to suitable spawning habitat and deterring them from poor habitat. Previous research has failed to explore Pacific lamprey response to predator odorants, although much research exists on attractant odorants. In our study, we tested Pacific lamprey response to …


Density Dependent Effects On Cutthroat And Brook Trout Behavioral Competition And Energy Expenditure, Ethan Daniel Green Jan 2015

Density Dependent Effects On Cutthroat And Brook Trout Behavioral Competition And Energy Expenditure, Ethan Daniel Green

All Master's Theses

Cutthroat Trout (Oncorhynchus clarki) are being displaced rangewide by invasive Brook Trout (Salvelinusfontinalis). There are many potential causes of displacement but the underlying mechanisms of the invasion and displacement are not well understood. Increased population densities in streams in which Cutthroat Trout and Brook Trout occur in sympatry appears to have detrimental effects on Cutthroat Trout. In this study, I compared the competitive behaviors and activity allocation patterns of Brook Trout and Cutthroat Trout at varying population densities in a simulated stream aquarium. I concluded that Brook Trout likely have a behavioral advantage over Cutthroat Trout …


Assessing The Contributions Of Two Stocked Strains On A Minnesota-Wisconsin Border Water, Douglas Zentner Jan 2015

Assessing The Contributions Of Two Stocked Strains On A Minnesota-Wisconsin Border Water, Douglas Zentner

Journal of Earth and Life Science

Stocking has long been used as a management tool in the United States even though many of its effects remain cryptic. Past comparisons between stocked strains were generally based on the survival and growth rates of physically marked individuals. More recently the use of genetic markers to assess contributions of stocked individuals has been employed by fisheries managers. Using 13 microsatellite markers we assessed the contributions of two muskellunge (Esox masquinongy) strains (Wisconsin and Leech) stocked into the St. Louis River Estuary. Ancestry in the adult samples remained relatively constant with differences only observed between the 2008 and …


Using Wild I.D. As A Reliable Source For Mark And Recapture Studies On Northern Pike (Esox Lucius), Martin Evans Jan 2015

Using Wild I.D. As A Reliable Source For Mark And Recapture Studies On Northern Pike (Esox Lucius), Martin Evans

Journal of Earth and Life Science

Mark and recapture studies are a very popular method fisheries biologists use to assess certain fish populations in lakes. This process can be very labor intensive and expensive. Wild I.D. is free software developed by Dartmouth College that uses SIFT program to find unique features in photographs. Initially developed for identification of African land mammals the program gives each photo a score and percent match to other photos. Northern pike were used in this study to determine if the program can recognize simulated recapture events. Photos of sample fish were taken at two separate locations, the photos were then copied …


Juvenile Chinook Salmon Diet In Comparison To Invertebrate Drift In The Merced River, California, Tyler Orgon Jan 2015

Juvenile Chinook Salmon Diet In Comparison To Invertebrate Drift In The Merced River, California, Tyler Orgon

Journal of Earth and Life Science

Diets and habitat types of salmonids have been widely studied in disturbed streams and rivers. The Merced River in California has a long history of flooding, damming, levee failures, and channel reconstruction events that has disrupted the aquatic ecosystem. This 30 day study was conducted in the Robinson Reach of the Merced River using juvenile Chinook salmon (Oncorhynchus tshawtscha). The objectives were to try and understand if juvenile Chinook salmon were selecting certain invertebrate species, determine if there were any differences in diets between habitat types, and determine whether diets and drift samples were different. Diets consisted of …


Effects Of Cooler Northern Waters On Growth Rates In Bluegill And Pumpkinseed Sunfish, Alec Spurbeck Jan 2015

Effects Of Cooler Northern Waters On Growth Rates In Bluegill And Pumpkinseed Sunfish, Alec Spurbeck

Journal of Earth and Life Science

The Centrarchidae family range spans all across the United States making them a favorite target for many recreational anglers. In northern Minnesota, most water bodies do not reach optimal growth temperatures for the sunfishes, putting them right on the edge of their suitable range and potentially slowing overall growth. Therefore, the main objectives of this study were to 1) determine if sunfish growth rates respond to the severity of winter and 2) investigate growth differences between two sunfish species. Growth rates of bluegill (Lepomis macrochirus) and pumpkinseed (Lepomis gibbosus) were estimated from Big Sugar Bush Lake, …


Spatial And Temporal Factors Influencing Northern Pike Fry Density Estimates, Nate Stott Jan 2015

Spatial And Temporal Factors Influencing Northern Pike Fry Density Estimates, Nate Stott

Journal of Earth and Life Science

The Tamarac River in northern Minnesota is an important spawning site for northern pike (Esox lucius) in the Red Lake system. However, little is known about fry production in the river. This study investigates migration densities and spatial and temporal factors influencing northern pike fry density estimates. Northern pike fry were collected with drift nets between 28 May and 4 June 2014. Thirty northern pike fry were randomly selected to have total length measured from each sample. Northern pike fry were observed in the first sample day. Northern pike fry density maxima occurred on 29 May at midnight …


A Genetic Based Approach To Management And Stocking Of Muskellunge, Douglas Zentner Jan 2015

A Genetic Based Approach To Management And Stocking Of Muskellunge, Douglas Zentner

Journal of Earth and Life Science

Fish stocking has long been used as a management tool among fisheries biologists and continues to be met with popular public opinion. Despite perceived simplicity, the full effects of stocking remain cryptic for many fish populations. Stocking has frequently been used to maintain or establish successful muskellunge (Esox masquinongy) populations. Coupled with other management practices the Minnesota Department of Natural Resources (MNDNR) has established Minnesota as a premier muskellunge fishery. From 1958 to 2012 the MNDNR stocked three strains of muskellunge in Big Mantrap Lake, MN. The first from Shoepack Lake, MN (hereafter Shoepack-strain) was used until the …


The Role Of Citizens In Detecting And Responding To A Rapid Marine Invasion, Steven B. Scyphers, Sean P. Powers, J. Lad Akins, J. Marcus Drymon, Charles W. Martin, Zeb H. Schobernd, Pamela J. Schofield, Robert L. Shipp, Theodore S. Switzer Jan 2015

The Role Of Citizens In Detecting And Responding To A Rapid Marine Invasion, Steven B. Scyphers, Sean P. Powers, J. Lad Akins, J. Marcus Drymon, Charles W. Martin, Zeb H. Schobernd, Pamela J. Schofield, Robert L. Shipp, Theodore S. Switzer

University Faculty and Staff Publications

Documenting and responding to species invasions requires innovative strategies that account for ecological and societal complexities. We used the recent expansion of Indo-Pacific lionfish (Pterois volitans/miles) throughout northern Gulf of Mexico coastal waters to evaluate the role of stakeholders in documenting and responding to a rapid marine invasion. We coupled an online survey of spearfishers and citizen science monitoring programs with traditional fishery-independent data sources and found that citizen observations documented lionfish 1–2 years earlier and more frequently than traditional reef fish monitoring programs. Citizen observations first documented lionfish in 2010 followed by rapid expansion and proliferation in …


The Status Of Fishes In The Missouri River, Nebraska: Shoal Chub (Macrhybopsis Hyostoma), Sturgeon Chub (M. Gelida), Sicklefin Chub (M. Meeki), Silver Chub (M. Storeriana), Flathead Chub (Platygobio Gracilis), Plains Minnow (Hybognathus Placitus), Western Silvery Minnow (H. Argyritis), And Brassy Minnow (H. Hankinsoni), Kirk D. Steffensen, Dane A. Shuman, Sam Stukel Dec 2014

The Status Of Fishes In The Missouri River, Nebraska: Shoal Chub (Macrhybopsis Hyostoma), Sturgeon Chub (M. Gelida), Sicklefin Chub (M. Meeki), Silver Chub (M. Storeriana), Flathead Chub (Platygobio Gracilis), Plains Minnow (Hybognathus Placitus), Western Silvery Minnow (H. Argyritis), And Brassy Minnow (H. Hankinsoni), Kirk D. Steffensen, Dane A. Shuman, Sam Stukel

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

Throughout the past century, the Missouri River has been highly modified which has negatively affected the native fish community. Previous research quantified the reduction of several native Cyprinidae species and made several recommendations to aid in recovery. However, these recommendations were not implemented. Therefore, the objective of this paper is to assess the current population trends of eight native cyprinid species and develop the current management objectives. Over 335,000 fish were collected from the Missouri River along Nebraska’s eastern border with mini-fyke nets and otter trawls from 2003 to 2012. Target Cyprinidae species consisted of less than five percent (n …


The Status Of Fishes In The Missouri River, Nebraska: Sauger (Sander Canadensis), Kirk D. Steffensen, Sam Stukel, Dane A. Shuman Dec 2014

The Status Of Fishes In The Missouri River, Nebraska: Sauger (Sander Canadensis), Kirk D. Steffensen, Sam Stukel, Dane A. Shuman

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

Early fisheries investigation of the Missouri River fish community indicated that Sauger were common throughout Nebraska, including all major Missouri River tributaries. However due to many factors, their current range is restricted to the Missouri River and the lower reaches of a few tributaries. Hesse (1994) recommended listing Sauger as a state endangered species but this recommendation was never implemented. Therefore, the objective of this paper is to reevaluate the current population status of Sauger in the Missouri River along Nebraska’s border. Over 2,100 Sauger have been captured from the Missouri River along Nebraska’s eastern border since 2003. Sauger were …


Variability In The Spatial And Temporal Patterns Of Larval Scombrid Abundance In The Gulf Of Mexico, Sennai Y. Habtes Nov 2014

Variability In The Spatial And Temporal Patterns Of Larval Scombrid Abundance In The Gulf Of Mexico, Sennai Y. Habtes

USF Tampa Graduate Theses and Dissertations

Accurate fishery-independent methods for assessing the abundance of marine fish stocks are important tools for proper pelagic fisheries management. The review and improvement of standardized sampling methods used in fisheries-independent sampling, and the establishment of improved models of abundance and population dynamics utilizing novel statistical techniques for fisheries management will further improve our understanding of the way in which marine fish stocks vary spatially and temporally. One of the most important and longest running surveys of fisheries-independent data in the Southeastern United States is the spring ichthyoplankton survey conducted through the Southeast Area Mapping and Assessment Program (SEAMAP).

These surveys …


Fisheries Management Paper No.266 - Exmouth Gulf Prawn Managed Fishery Bycatch Action Plan 2014-2019. Version 1.0, Department Of Fisheries, Western Australia Nov 2014

Fisheries Management Paper No.266 - Exmouth Gulf Prawn Managed Fishery Bycatch Action Plan 2014-2019. Version 1.0, Department Of Fisheries, Western Australia

Fisheries Management Papers

Bycatch is described as the part of the catch which is returned to the sea (usually referred to as non-retained or discarded) either because it has no commercial value or because legislative requirements preclude it being retained. Thus, this Bycatch Action Plan (BAP) includes unmarketable finfish and invertebrate species, along with endangered, threatened and protected (ETP) species, such as marine mammals, reptiles and some elasmobranchs.

It is Government policy to minimise bycatch in all commercial fisheries. This BAP details a program of actions to address bycatch issues in the Exmouth Gulf Prawn Managed Fishery (EGPMF), in accordance with the EGPMF …


Fisheries Management Paper No.265 - Exmouth Gulf Prawn Managed Fishery Harvest Strategy 2014 - 2019 Version 1.0, Department Of Fisheries Western Australia Nov 2014

Fisheries Management Paper No.265 - Exmouth Gulf Prawn Managed Fishery Harvest Strategy 2014 - 2019 Version 1.0, Department Of Fisheries Western Australia

Fisheries Management Papers

This fishery-specific harvest strategy has been developed in line with the Department of Fisheries' (Department) over-arching Harvest Strategy Policy for Aquatic Resources (Department of Fisheries in prep.) and in consultation with licensees. The broad scope of the Harvest Strategy Policy for Aquatic Resources is consistent with the National Harvest Strategy Guidelines but as well as considering all retained target species, it also incorporates retained non-target species, bycatch' and other ecological components to ensure the risks to these elements are managed effectively.

The Exmouth Gulf Prawn Managed Fishery (EGPMF) harvest strategy outlines the longand short-term fishery-specific management objectives; a description of …


Spatiotemporal Variation In Flow-Dependent Recruitment Of Long-Lived Riverine Fish: Model Development And Evaluation, Daisuke Goto, Martin J. Hamel, Jeremy J. Hammen, Mathew L. Rugg, Mark A. Pegg, Valery E. Forbes Nov 2014

Spatiotemporal Variation In Flow-Dependent Recruitment Of Long-Lived Riverine Fish: Model Development And Evaluation, Daisuke Goto, Martin J. Hamel, Jeremy J. Hammen, Mathew L. Rugg, Mark A. Pegg, Valery E. Forbes

School of Biological Sciences: Faculty Publications

Abstract Natural flow regimes can play a major role as an overarching ecosystem driver in reproduction and recruitment of riverine fishes. Human needs for freshwater however have altered hydrology of many riverine systems worldwide, threatening fish population sustainability. To understand and predict how spatiotemporal dynamics of flow regimes influence reproductive and recruitment variability, and ultimately population sustainability of shovelnose sturgeon (Scaphirhynchus platorynchus), we develop a spatially explicit (1D) individual-based population model that mechanistically (via energetics-based processes) simulates daily activities (dispersal, spawning, foraging, growth, and survival). With field observations of sturgeon and habitat conditions in a major tributary of …


The Status Of Fishes In The Missouri River, Nebraska: Lake Sturgeon (Acipenser Fulvescens), Kirk D. Steffensen, Sam Stukel, Dane A. Shuman Oct 2014

The Status Of Fishes In The Missouri River, Nebraska: Lake Sturgeon (Acipenser Fulvescens), Kirk D. Steffensen, Sam Stukel, Dane A. Shuman

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

Lake Sturgeon (Acipenser fulvescens) occurrences in the Missouri River along Nebraska’s eastern border are historically sporadic and rare. Presently, the wild Lake Sturgeon population in this river reach may be extirpated. A Recovery Program initiated by the Missouri Department of Conservation (MDC) has stocked almost 150,000 hatchery-reared Lake Sturgeon into the lower Missouri River at several sites in Missouri. As a result, the number of Lake Sturgeon collected has increased. Since monitoring began in 2003, no Lake Sturgeon have been collected above Gavins Point Dam while 40 fish were collected downstream of Gavins Point Dam. The majority of …


Historical Vegetation Of Three Salmon-Bearing Watersheds In The Interior Columbia River Basin, Tyanna Smith Oct 2014

Historical Vegetation Of Three Salmon-Bearing Watersheds In The Interior Columbia River Basin, Tyanna Smith

PSU McNair Scholars Online Journal

Land use practices can be a contributing factor to environmental degradation and have been the focus of many ecological studies. One aspect that is less addressed is land use history and the effects that past practices, such as logging and grazing, can have on the current landscape. This paper describes research and the synthesis of material on the environmental history and watershed characteristics for three watersheds located within spawning and rearing areas for Chinook salmon in the Grande Ronde River Basin in Northeast Oregon: upper Grande Ronde River, Catherine Creek, and Minam River. The Grande Ronde Basin is critical spawning …


Predictors Patterns And Processes Of Extinction Risk In Porgies And Seabreams (Family: Sparidae), Mia Theresa B. Conteros Oct 2014

Predictors Patterns And Processes Of Extinction Risk In Porgies And Seabreams (Family: Sparidae), Mia Theresa B. Conteros

Biological Sciences Theses & Dissertations

A variety of human-induced changes are having profound impacts on the marine environment, and no area on the planet remains unaffected by the detrimental effects of our activities. These stressors can potentially lead to synergistic effects, causing accelerated biodiversity loss and diminished ecosystem functioning. Identification and understanding of the factors that drive species to heightened risk of extinction are important goals in conservation.

The Sparidae are commercially important and ecologically complex marine fishes; global extinction risk assessments using the IUCN Red List of Threatened Species methodology show that 9% (13 species) have increased vulnerability to population declines from intense fishing …


The Status Of Fishes In The Missouri River, Nebraska: Shovelnose Sturgeon (Scaphirhynchus Platorynchus), Kirk D. Steffensen, Sam Stukel, Dane A. Shuman Sep 2014

The Status Of Fishes In The Missouri River, Nebraska: Shovelnose Sturgeon (Scaphirhynchus Platorynchus), Kirk D. Steffensen, Sam Stukel, Dane A. Shuman

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

The Shovelnose Sturgeon Scaphirhynchus platorynchus remains the most abundant riverine sturgeon species in North American despite the anthropogenic modifications that have occurred throughout their historic range; however, their populations have declined throughout Nebraska since the construction of Fort Randall and Gavins Point Dams. Therefore, the objective of this study was to present the current status of Shovelnose Sturgeon in the Missouri River along Nebraska’s border. Data was acquired from 2003 to 2012 from all reaches of the Missouri River along Nebraska’s eastern border. Catch rates of Shovelnose Sturgeon increased in a downstream trend and were highest in the reach below …


The Status Of Fishes In The Missouri River, Nebraska: Pallid Sturgeon (Scaphirhynchus Albus), Kirk D. Steffensen, Dane A. Shuman, Robert A. Klumb, Sam Stukel Sep 2014

The Status Of Fishes In The Missouri River, Nebraska: Pallid Sturgeon (Scaphirhynchus Albus), Kirk D. Steffensen, Dane A. Shuman, Robert A. Klumb, Sam Stukel

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

Anthropogenic alterations to the Missouri River have placed the Pallid Sturgeon (Scaphirhynchus albus) population in jeopardy and contributed to their listing as an endangered species. Pallid sturgeon were always less common than the sympatric Shovelnose Sturgeon (S. platorynchus); however, Pallid Sturgeon seemed to be more affected by river alterations as the river sturgeon ratio has become more skewed towards Shovelnose Sturgeon. Shortly after listing, population augmentation with hatchery produced Pallid Sturgeon began to supplement the diminishing wild population. Therefore, the objective of this study was to present the current population status of the Pallid Sturgeon in …


South Atlantic Stream Fish Assemblages: Multi-Scale Structuring Factors, Trait Associations And Channelization, And Responses To Dam Removal, Cathy Marion Aug 2014

South Atlantic Stream Fish Assemblages: Multi-Scale Structuring Factors, Trait Associations And Channelization, And Responses To Dam Removal, Cathy Marion

All Dissertations

South Atlantic coastal plain wadeable streams are unique and understudied freshwater environments that provide crucial habitats for a wide range of aquatic taxa. In Chapter 1, we investigated patterns in fish assemblages across South Carolina's coastal plain, and developed statistical models to identify the dominant multi-scale abiotic environmental factors that influence assemblage structure. Our analyses indicated the presence of four predominant fish assemblages that commonly occur in the coastal plain, which we termed the: 1) fluvial, 2) eastern mudminnow, 3) centrarchid, and 4) non-fluvial assemblages. Natural geographic gradients and instream habitat parameters associated with velocity, channel form, stream size, and …