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Articles 271 - 300 of 721

Full-Text Articles in Aquaculture and Fisheries

Multilocus And Parametric Analyses Of The Evolutionary History Of The Amazonian Peacock Cichlids, The Genus Cichla (Teleostei: Cichlidae), Stuart Clayton Willis Apr 2011

Multilocus And Parametric Analyses Of The Evolutionary History Of The Amazonian Peacock Cichlids, The Genus Cichla (Teleostei: Cichlidae), Stuart Clayton Willis

School of Biological Sciences: Dissertations, Theses, and Student Research

Accurate knowledge of species boundaries and species phylogeny are fundamental to testing hypotheses of recent evolutionary processes, but the estimation of these partitions is challenging due both to inherent confusion about what is being estimated as well as the data available to estimate them. Using multilocus data from mtDNA, microsatellites, and nuclear locus sequences of over 1100 individuals, we delimited eight separately evolving species of Cichla rather than the 15 described. Among species we found evidence of rare but widespread introgressive hybridization, while within these species we observed evidence of long-term gene exchange and constrained evolutionary trajectories. In most cases …


The 100th Meridian Initiative: A Strategic Approach To Prevent The Westward Spread Of Zebra Mussels And Other Aquatic Nuisance Species, Susan Mangin Mar 2011

The 100th Meridian Initiative: A Strategic Approach To Prevent The Westward Spread Of Zebra Mussels And Other Aquatic Nuisance Species, Susan Mangin

United States Fish and Wildlife Service: Publications

Zebra mussels are prolific alien invaders that have rapidly become
established in waters of the eastern United States and Canada. These
natives of the Black, Caspian, Azov and Aral Sea drainage basins were first
discovered in Lake St. Clair near Detroit, Michigan, in 1988. By 1991, they
had spread throughout the Great Lakes basin and are now established
throughout the Mississippi River basin and are spreading west into
Oklahoma. Except for Oklahoma, zebra mussels have not been detected in
open waters of the West. However, without effective prevention measures,
their invasion into the West is a real and imminent possibility. …


2010 Vegetation Survey Of The Fort Niobrara National Wildlife Refuge (Final Report To The Nebraska Game And Parks Commission, U.S. Fish And Wildlife Service, And The Sandhills Prairie Refuge Association), Robert F. Steinauer Jan 2011

2010 Vegetation Survey Of The Fort Niobrara National Wildlife Refuge (Final Report To The Nebraska Game And Parks Commission, U.S. Fish And Wildlife Service, And The Sandhills Prairie Refuge Association), Robert F. Steinauer

Nebraska Game and Parks Commission: White Papers, Conference Presentations, and Manuscripts

Fort Niobrara National Wildlife Refuge (FNNWR) is located on the Niobrara River in north central Cherry County, NE. There is little detailed information available documenting the vegetation of FNNWR. Tolstead (1942) studied the grasslands of northern Cherry County, (including FNNWR) with a focus on describing the dominant species of grassland types and determining the relationships between vegetation distribution and environmental variables and management practices. Churchill et al (1988) described the vascular flora of The Nature Conservancy’s nearby Niobrara Valley Preserve. Fiest et al (2010) conducted vascular plant surveys on portions of the FNNWR in 2009 and compiled a partial vascular …


Implications Of Community Concordance For Assessing Stream Integrity At Three Nested Spatial Scales In Minnesota, U.S.A., Christine L. Dolph, David D. Huff, Christopher J. Chizinski, Bruce Vondracek Jan 2011

Implications Of Community Concordance For Assessing Stream Integrity At Three Nested Spatial Scales In Minnesota, U.S.A., Christine L. Dolph, David D. Huff, Christopher J. Chizinski, Bruce Vondracek

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

1. Fish and invertebrate assemblage data collected from 670 stream sites in Minnesota (U.S.A.) were used to calculate concordance across three nested spatial scales (statewide, ecoregion and catchment). Predictive taxa richness models, calibrated using the same data, were used to evaluate whether concordant communities exhibited similar trends in human-induced taxa loss across all three scales. Finally, we evaluated the strength of the relationship between selected environmental variables and the composition of both assemblages at all three spatial scales.

2. Significant concordance between fish and invertebrate communities occurred at the statewide scale as well as in six of seven ecoregions and …


Using The Judas Technique To Locate And Remove Wintertime Aggregations Of Invasive Common Carp, P. G. Bajer, Christopher J. Chizinski, P. W. Sorensen Jan 2011

Using The Judas Technique To Locate And Remove Wintertime Aggregations Of Invasive Common Carp, P. G. Bajer, Christopher J. Chizinski, P. W. Sorensen

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Radio- and acoustic telemetry in three Midwestern lakes demonstrated that common carp, Cyprinus carpio L., aggregate as water temperatures descend below 10C. Particularly dense aggregations formed at temperatures <5 >C, and once located, these aggregations could be removed with an efficiency of up to 94% using seine nets. Carp aggregated just below the surface of the ice (approximately 1.5 m) and rarely descended to warmer waters, which extended down to 10 m. Although aggregations consistently formed close to shore, their locations could not be explained by temperature or dissolved oxygen. The aggregations also moved frequently, making radio-tagged fish invaluable to locate …


Mixed-Source Reintroductions Lead To Outbreeding Depression In Second-Generation Descendents Of A Native North American Fish, David D. Huff, Loren M. Miller, Christopher J. Chizinski, Bruce Vondracek Jan 2011

Mixed-Source Reintroductions Lead To Outbreeding Depression In Second-Generation Descendents Of A Native North American Fish, David D. Huff, Loren M. Miller, Christopher J. Chizinski, Bruce Vondracek

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Reintroductions are commonly employed to preserve intraspecific biodiversity in fragmented landscapes. However, reintroduced populations are frequently smaller and more geographically isolated than native populations. Mixing genetically, divergent sources are often proposed to attenuate potentially low genetic diversity in reintroduced populations that may result from small effective population sizes. However, a possible negative tradeoff for mixing sources is outbreeding depression in hybrid offspring. We examined the consequences of mixed-source reintroductions on several fitness surrogates at nine slimy sculpin (Cottus cognatus) reintroduction sites in south-east Minnesota. We inferred the relative fitness of each crosstype in the reintroduced populations by comparing …


Breeding Bird Response To Partially Harvested Riparian Management Zones, Christopher J. Chizinski, Anna Peterson, Joann Hanowski, Charles R. Blinn, Bruce Vondracek, Gerald J. Niemi Jan 2011

Breeding Bird Response To Partially Harvested Riparian Management Zones, Christopher J. Chizinski, Anna Peterson, Joann Hanowski, Charles R. Blinn, Bruce Vondracek, Gerald J. Niemi

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

We compared avian communities among three timber harvesting treatments in 45-m wide even-age riparian management zones (RMZs) placed between upland clearcuts and along one side of first- or second-order streams in northern Minnesota, USA. The RMZs had three treatments: (1) unharvested, (2) intermediate residual basal area (RBA) (targeted goal 11.5m2/ha, realized 16.0m2/ha), and (3) low RBA (targeted goal 5.7m2/ha, realized 8.7m2/ha). Surveys were conducted one year pre-harvest and three consecutive years post-harvest. There was no change in species richness, diversity, or total abundance associated with harvest but there were shifts in the types of …


Ultimate Biochemical Oxygen Demand In Semi-Intensively Managed Shrimp Pond Waters, Bartholomew W. Green, George H. Ward Jan 2011

Ultimate Biochemical Oxygen Demand In Semi-Intensively Managed Shrimp Pond Waters, Bartholomew W. Green, George H. Ward

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Three independent studies were conducted to quantify ultimate biochemical oxygen demand (UBOD) and the corresponding decomposition rate constant for production pond (average 21.5 ha each) waters and effluents on six semi-intensively managed marine shrimp (Litopenaeus vannamei) farms in Honduras. Samples were collected during the rainy season in studies 1-3 and during the dry season only in study 1. Pond water samples were collected during the culture period and/or at harvest. The dry season 30-d biochemical oxygen demand (BOD30) of pond waters across all farms was 26% lower and UBOD was 54% lower, but the decomposition rate …


Yellowthroat: Wildlife Management Area Jan 2011

Yellowthroat: Wildlife Management Area

United States Fish and Wildlife Service: Publications

Yellowthroat Wildlife Management Area (WMA) is managed as part of the National Wildlife Refuge System by the Fort Niobrara / Valentine National Wildlife Refuges complex staff. Yellowthroat WMA is a 480-acre area managed for migratory birds. Our goal is to restore this former cropland to native prairie by using management techniques such as prescribed burning, grazing, weed control, water level manipulations, and planting native grasses. A variety of wildlife can be seen in the wetlands and grasslands, including the yellow-throated warbler for which the place is named.


Spatial And Temporal Patterns And The Influence Of Abiotic Factors On Larval Fish Catches In The Lower Niobrara River, Nebraska, Greg A. Wanner, Kristen L. Grohs, Robert A. Klumb Jan 2011

Spatial And Temporal Patterns And The Influence Of Abiotic Factors On Larval Fish Catches In The Lower Niobrara River, Nebraska, Greg A. Wanner, Kristen L. Grohs, Robert A. Klumb

United States Fish and Wildlife Service: Publications

The Niobrara River has a natural hydrograph and temperature regime with the lower 32 km protected under the National Wild and Scenic River system managed by the National Park Service. The largest threat to this river is decreased instream flows due to water withdrawals for agriculture. The Niobrara River a large tributary to the Missouri River may positively influence fish production. However, no information exists regarding phenology of fish spawning or what abiotic factors may influence spawning. Our objectives were to examine the taxonomic composition and the spatial and temporal patterns of the larval fish assemblage in relation to environmental …


Comparative Production Of Channel Catfish And Channel × Blue Hybrid Catfish Subjected To Two Minimum Dissolved Oxygen Concentrations, Bartholomew W. Green, Steven D. Rawles Jan 2011

Comparative Production Of Channel Catfish And Channel × Blue Hybrid Catfish Subjected To Two Minimum Dissolved Oxygen Concentrations, Bartholomew W. Green, Steven D. Rawles

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

The effect of daily minimum dissolved oxygen (DO) concentration on the growth and yield of channel catfish Ictalurus punctatus and channel catfish hybrids (female channel catfish × male blue catfish I. furcatus) sharing the Jubilee strain of channel catfish as the maternal parent was evaluated in a 234-d study in sixteen 0.1-ha earthen ponds (15,113 fish/ha). Ponds were managed to maintain a minimum DO concentration of 25% or 50% of saturation. The total consumption of 32%-protein feed at the high and low DO concentrations was 12,973 and 10,262 kg/ha, respectively, for channel catfish and 12,805 and 11,592 kg/ha, …


Development Of Phytoplankton Communities And Common Off-Flavors In A Biofloc Technology System Used For The Culture Of Channel Catfish (Ictalurus Punctatus), Kevin Schrader, Bartholomew W. Green, Peter Perschbacher Jan 2011

Development Of Phytoplankton Communities And Common Off-Flavors In A Biofloc Technology System Used For The Culture Of Channel Catfish (Ictalurus Punctatus), Kevin Schrader, Bartholomew W. Green, Peter Perschbacher

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

The use of biofloc technology production systems continues to increase in the aquaculture industry worldwide. Recent research demonstrated that outdoor biofloc systems can be used to produce high yields of channel catfish (Ictalurus punctatus). However, studies have not yet been performed to determine the development and composition of phytoplankton communities and related off-flavor problems in these biofloc production systems. In this study, water samples were collected biweekly from May to November and channel catfish samples were collected during harvest in November from nine 18.6 m2 biofloc culture tanks. Water and fillet samples were analyzed for levels of …


Communication For Mate Selection In Anurans: Dominant Frequency Versus Snout-Vent-Length, Shari Jean Kunert Dec 2010

Communication For Mate Selection In Anurans: Dominant Frequency Versus Snout-Vent-Length, Shari Jean Kunert

Department of Environmental Studies: Undergraduate Student Theses

No abstract provided.


Match–Mismatch Regulation For Bluegill And Yellow Perch Larvae And Their Prey In Sandhill Lakes, Jeffrey C. Jolley, David W. Willis, Richard S. Holland Nov 2010

Match–Mismatch Regulation For Bluegill And Yellow Perch Larvae And Their Prey In Sandhill Lakes, Jeffrey C. Jolley, David W. Willis, Richard S. Holland

Nebraska Game and Parks Commission: Staff Research Publications

Food availability may regulate fish recruitment, both directly and indirectly. The availability of zooplankton, especially to newly hatched larvae, is thought to be crucial to their early growth and survival. We examined stomach contents of larval bluegill Lepomis macrochirus and yellow perch Perca flavescens in Pelican Lake and Cameron Lake, Nebraska, in 2004 and 2005. We also determined zooplankton availability and calculated prey selection using Chesson’s a. In addition, we investigated potential match–mismatch regulation of recruitment from 2004 to 2008. Bluegill positively selected copepod nauplii and Bosmina spp., and yellow perch often selected copepods. Abundant zooplankton populations were available for …


Alaska Reflections: A Sampler Jun 2010

Alaska Reflections: A Sampler

United States Fish and Wildlife Service: Publications

Table of Contents:

A Glacier Bird in Retreat
Bridging the Slough
The Great Eider Egg Hunt
Subsistence is for the Birds
Many are Cold, Few were Frozen
Experience is the Best Teacher
Reflecting


Multi-Host Model-Based Identification Of Armillifer Agkistrodontis (Pentastomida), A New Zoonotic Parasite From China, Shao-Hong Chen, Qin Liu, Yong-Nian Zhang, Jia-Xu Chen, Hao Li, Ying Chen, Peter Steinmann, Xiao-Nong Zhou Apr 2010

Multi-Host Model-Based Identification Of Armillifer Agkistrodontis (Pentastomida), A New Zoonotic Parasite From China, Shao-Hong Chen, Qin Liu, Yong-Nian Zhang, Jia-Xu Chen, Hao Li, Ying Chen, Peter Steinmann, Xiao-Nong Zhou

Harold W. Manter Laboratory of Parasitology: Library Materials

Background: Pentastomiasis is a rare parasitic infection of humans. Pentastomids are dioecious obligate parasites requiring multiple hosts to complete their life cycle. Despite their worm-like appearance, they are commonly placed into a separate sub-class of the subphylum Crustacea, phylum Arthropoda. However, their systematic position is not uncontested and historically, they have been considered as a separate phylum.

Methodology/Principal Findings: An appraisal of Armillifer agkistrodontis was performed in terms of morphology and genetic identification after its lifecycle had been established in a multi-host model, that is, mice and rats as intermediate hosts, and snakes (Agkistrodon acutus and Python molurus) …


The Influence Of Partial Timber Harvesting In Riparian Buffers On Macroinvertebrate And Fish Communities In Small Streams In Minnesota, Usa, Christopher J. Chizinski, Bruce Vondracek, Charles R. Blinn, Raymond M. Newman, Dickson M. Atuke, Keith Fredricks, Nathaniel A. Hemstad, Eric Merten, Nicholas Schlesser Feb 2010

The Influence Of Partial Timber Harvesting In Riparian Buffers On Macroinvertebrate And Fish Communities In Small Streams In Minnesota, Usa, Christopher J. Chizinski, Bruce Vondracek, Charles R. Blinn, Raymond M. Newman, Dickson M. Atuke, Keith Fredricks, Nathaniel A. Hemstad, Eric Merten, Nicholas Schlesser

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Relatively few evaluations of aquatic macroinvertebrate and fish communities have been published in peer-reviewed literature detailing the effect of varying residual basal area (RBA) after timber harvesting in riparian buffers. Our analysis investigated the effects of partial harvesting within riparian buffers on aquatic macroinvertebrate and fish communities in small streams from two experiments in northern Minnesota northern hardwood-aspen forests. Each experiment evaluated partial harvesting within riparian buffers. In both experiments, benthic macroinvertebrates and fish were collected 1 year prior to harvest and in each of 3 years after harvest. We observed interannual variation for the macroinvertebrate abundance, diversity and taxon …


Assessment Of Selenium And Atrazine Exposure And Effects To Wildlife At The North Platte National Wildlife Refuge, Scottsbluff, Nebraska, Matthew S. Schwarz, Christina D. Lydick Jan 2010

Assessment Of Selenium And Atrazine Exposure And Effects To Wildlife At The North Platte National Wildlife Refuge, Scottsbluff, Nebraska, Matthew S. Schwarz, Christina D. Lydick

United States Fish and Wildlife Service: Publications

This study evaluated selenium and atrazine exposure and effects to fish and wildlife at North Platte National Wildlife Refuge (Refuge) in Scotts Bluff County, Nebraska. Atrazine was detected in 2 of 54 water samples and at low concentrations that are not of concern. However, concentrations of selenium and strontium exceeded toxicity guidelines in water, sediment, invertebrates, whole-body fish and wood duck eggs. Concentrations of selenium in water at Refuge sites frequently exceeded a 2 μg/L total recoverable threshold for selenium bioaccumulation and were greatest at Stateline Island (9.7 μg/L) and Little Lake Alice (24 μg/L). In sediments, strontium concentrations were …


Endangered And Threatened Wildlife And Plants; Designation Of Critical Habitat For The Salt Creek Tiger Beetle Jan 2010

Endangered And Threatened Wildlife And Plants; Designation Of Critical Habitat For The Salt Creek Tiger Beetle

United States Fish and Wildlife Service: Publications

We, the U.S. Fish and Wildlife Service (Service/USFWS), designate critical habitat for the Salt Creek tiger beetle (Cicindela nevadica lincolniana) under the Endangered Species Act of 1973, as amended (Act). In total, approximately 1,933 acres (ac) (782 hectares (ha)) located in Lancaster and Saunders Counties, Nebraska, fall within the boundaries of the critical habitat designation.


The Index Of Biological Integrity And The Bootstrap: Can Random Sampling Error Affect Stream Impairment Decisions?, Christine L. Dolph, Aleksey Y. Sheshukov, Christopher J. Chizinski, Bruce Vondracek, Bruce N. Wilson Jan 2010

The Index Of Biological Integrity And The Bootstrap: Can Random Sampling Error Affect Stream Impairment Decisions?, Christine L. Dolph, Aleksey Y. Sheshukov, Christopher J. Chizinski, Bruce Vondracek, Bruce N. Wilson

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Multimetric indices, such as the Index of Biological Integrity (IBI), are increasingly used bymanagement agencies to determine whether surface water quality is impaired. However, important questions about the variability of these indices have not been thoroughly addressed in the scientific literature. In this study, we used a bootstrap approach to quantify variability associated with fish IBIs developed for streams in two Minnesota river basins. We further placed this variability into a management context by comparing it to impairment thresholds currently used in water quality determinations for Minnesota streams. We found that 95% confidence intervals ranged as high as 40 points …


The Impact Of Rare Taxa On A Fish Index Of Biotic Integrity, Haibo Wan, Christopher J. Chizinski, Christine L. Dolph, Bruce Vondracek, Bruce N. Wilson Jan 2010

The Impact Of Rare Taxa On A Fish Index Of Biotic Integrity, Haibo Wan, Christopher J. Chizinski, Christine L. Dolph, Bruce Vondracek, Bruce N. Wilson

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

The index of biotic integrity (IBI) is a commonly used bioassessment tool that integrates abundance and richness measures to assess water quality. In developing IBIs that are both responsive to human disturbance and resistant to natural variability and sampling error, water managersmust decide how to weigh information about rare and abundant taxa, which in turn requires an understanding of the sensitivity of indices to rare taxa. Herein, we investigated the influence of rare fish taxa (within the lower 5% of rank abundance curves) on IBI metric and total scores for stream sites in two of Minnesota’smajor river basins, the St. …


Einige Bemerkungen Zur Biologie Der Wüstenkröte (Bufo Raddei), Ellen Driechciarz, René Driechciarz Jan 2010

Einige Bemerkungen Zur Biologie Der Wüstenkröte (Bufo Raddei), Ellen Driechciarz, René Driechciarz

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

Some localities in the Taatsyn river in the valley of the Great Lakes in the South of Changaj in Mongolia were found to harbor Bufo raddei. The authors collected data on population density and tadpole holes of the larvae, collected for the first time from this Asian amphibian species.


Threadfin Shad Impacts Phytoplankton And Zooplankton Community Structures In Channel Catfish Ponds, Bartholomew W. Green, Peter Perschbacher, Gerald Ludwig, Sara E. Duke Jan 2010

Threadfin Shad Impacts Phytoplankton And Zooplankton Community Structures In Channel Catfish Ponds, Bartholomew W. Green, Peter Perschbacher, Gerald Ludwig, Sara E. Duke

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Plankton community structure and chlorophyll a concentration were compared in 12 0.1-ha earthen ponds co-stocked with channel catfish (Ictalurus punctatus Rafinesque, 1818) in multiple-batch culture (initial biomass = 5,458 kg ha-1) and a planktivore, threadfin shad (Dorosoma petenense Güther, 1867; initial biomass = 449 kg ha-1), during the April-November growing season. We used a completely randomized design in 2 x 2 factorial arrangement to test planktivore level (presence or absence of threadfin shad) and channel catfish feeding frequency (daily or every 3rd d). Channel catfish were fed a 32% protein feed to apparent …


Retention, Movement, And The Biotic Response To Large Woody Debris In The Channelized Missouri River, Michael W. Archer Jan 2010

Retention, Movement, And The Biotic Response To Large Woody Debris In The Channelized Missouri River, Michael W. Archer

School of Natural Resources: Dissertations, Theses, and Student Research

Large woody debris (LWD) is an important component of a healthy aquatic ecosystem. However, little is known about the dynamics of LWD in a large, channelized river such as the Missouri River. My objectives were to first, assess the abundance of LWD found along the channelized portion of the Missouri River. Second, I documented movement of LWD that entered the river. Lastly, using PRIMER software I analyzed what effect, if any, river segments, bend types, and LWD had on the community composition of the macroinvertebrate and fish that inhabit the river. Abundance of LWD was greater along bends that have …


Comparative Growth And Yield Of Channel Catfish And Channel X Blue Hybrid Catfish Fed A Full Or Restricted Ration, Bartholomew W. Green, Steven Rawles Jan 2010

Comparative Growth And Yield Of Channel Catfish And Channel X Blue Hybrid Catfish Fed A Full Or Restricted Ration, Bartholomew W. Green, Steven Rawles

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Growth and yield (kg/ha-1) of the channel catfish (Ictalurus punctatus, Rafinesque, 1818) and the channel x blue hybrid catfish [I. punctatus female x I. furcatus (Lesueur,1840) male], which shared the Jubilee strain of channel catfish as the maternal parent, were compared in sixteen 0.1 ha earthen ponds (14,852 fish/ha-1) during the April to November growing season. Each fish genetic group was fed a commercially formulated 32% protein feed daily to apparent satiation or at 80% of the mean daily satiation ration. Net yield and individual weight were higher for channel x …


Effect Of Channel Catfish Stocking Rate On Yield And Water Quality In An Intensive, Mixed Suspended-Growth Production System, Bartholomew W. Green Dec 2009

Effect Of Channel Catfish Stocking Rate On Yield And Water Quality In An Intensive, Mixed Suspended-Growth Production System, Bartholomew W. Green

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

This study was conducted to determine the effect of stocking rate on yield of channel catfish Ictalurus punctatus and water quality in a mixed suspended-growth (biofloc) production system with zero water exchange. Channel catfish (National Warmwater Aquaculture Center 103 strain; average fish weight -- 13 g) were stocked into nine 35-m2 tanks (28 m3/tank) at a rate of 2.9, 5.7, or 8.5 fish/m2 for a 238-d grow-out period. One 1.865-kW blower for every three tanks supplied air continuously through a diffuser grid (constructed of 2.5-cm-diameter polyvinyl chloride pipe) on the bottom of each tank. Well water …


Press Release: No Rats Found, Lab Results On Six Bird Tests Received Jul 2009

Press Release: No Rats Found, Lab Results On Six Bird Tests Received

United States Fish and Wildlife Service: Publications

The U.S. Fish and Wildlife Service has received laboratory results on an initial group of bird carcasses collected on Rat Island in late May and Early April. Examination of the livers of two bald eagles, two glaucus winged gulls, one peregrine falcon, and one rock sandpiper all tested positive for the rodenticide brodifacoum. We are in the process of analyzing all of the viable bird remains and tissue samples collected, in order to more fully understand the cause of mortalities and more effectively plan future operations in the Aleutians. Results will be released when they are available. In addition, soil …


Reports From Rat Island Reflect Successes And Concerns Jun 2009

Reports From Rat Island Reflect Successes And Concerns

United States Fish and Wildlife Service: Publications

After more than two weeks of intensive field monitoring on Alaska’s remote Rat Island, part of Alaska Maritime National Wildlife Refuge, which was treated last year in an effort to eliminate invasive rats and restore seabird populations and other parts of the native ecosystem, biologists have found no sign of the invasive rats that have decimated native bird populations for more than 200 years. The same studies have documented that several bird species, including Aleutian cackling geese, ptarmigan, peregrine falcons, and black oyster catchers are nesting on the ten-square-mile island.


Final Report -- Missouri River Fish And Wildlife Mitigation Program: Fish Community Monitoring And Habitat Assessment Of Off-Channel Mitigation Sites, Van Sterner, Royce Bowman, Brandon L. Eder, Sabrina Negus, Gerald Mestl, Kasey Whiteman, Darrick Garner, Vince Travnichek, Joshua Schloesser, Joseph Mcmullen, Tracy Hill Apr 2009

Final Report -- Missouri River Fish And Wildlife Mitigation Program: Fish Community Monitoring And Habitat Assessment Of Off-Channel Mitigation Sites, Van Sterner, Royce Bowman, Brandon L. Eder, Sabrina Negus, Gerald Mestl, Kasey Whiteman, Darrick Garner, Vince Travnichek, Joshua Schloesser, Joseph Mcmullen, Tracy Hill

Nebraska Game and Parks Commission: Staff Research Publications

The Missouri River has been developed for flood control, commercial navigation, irrigation, fish and wildlife conservation, municipal water supply, water quality control and hydropower production through a series of congressional acts. However, prior to development, the lower Missouri River was characterized by a highly sinuous to braided channel with abundant log jams, sand bars, secondary channels and cut-off channels. Construction of the Bank Stabilization and Navigation Project (BSNP) converted the lower Missouri River into a narrow, self scouring channel. The active channel downstream of Sioux City, Iowa was as wide as 1.8 km before river modification, but is now confined …


Seasonal Variation Of Ectosymbiotic Ciliates On Farmed And Wild Shrimps From Coastal Yucatan, Mexico, Norma A. López-Téllez, Victor M. Vidal-Martínez, Robin M. Overstreet Feb 2009

Seasonal Variation Of Ectosymbiotic Ciliates On Farmed And Wild Shrimps From Coastal Yucatan, Mexico, Norma A. López-Téllez, Victor M. Vidal-Martínez, Robin M. Overstreet

Harold W. Manter Laboratory of Parasitology: Faculty Publications

High levels of ciliate infestation can affect respiration, feed intake, and locomotion in farmed shrimps in the tropics. Information on seasonal variation of the infestation parameters of ciliates is scarce, but it would be useful for determining the suitability of preventive measures or therapeutic treatment if necessary. This study aimed to describe the prevalence and mean intensity of infestation (MII) of ciliates on wild native shrimps Penaeus (Farfantepenaeus) brasiliensis and P. (Farfantepenaeus) duorarum and farm-cultured juvenile shrimp Penaeus (Litopenaeus) vannamei over an annual cycle and to determine whether an association existed among physicochemical factors …