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A Study Of The Effects Of Probait On Chuditch, Dasyurus Geoffroii, Within The Julimar Conservation Park With Notes On The General Ecology, Melissa York Jan 2005

A Study Of The Effects Of Probait On Chuditch, Dasyurus Geoffroii, Within The Julimar Conservation Park With Notes On The General Ecology, Melissa York

Theses : Honours

Broad scale fox baiting programs have been underway in Western Australia since 1996 when the Western Shield fauna recovery program commenced with the aim of recovering many fauna species that are under threat of extinction. Until recently, effective fox control for fauna recovery has been achieved with dried meat baits impregnated with the poison 1080. The Department of Conservation and Land Management (CALM) has developed more readily available and cost effective sausage meat baits, termed Probait. As bait acceptability trials in the laboratory indicated a potential risk from Pro bait ingestion by chuditch (Dasyurus geoffroii), assessment of the likely risk …


Natural Resource Management Issues For The South Coast Regional Strategy, B Nicholas Jan 2005

Natural Resource Management Issues For The South Coast Regional Strategy, B Nicholas

Resource management technical reports

This report has been prepared by the Agricultural Resource Management Program of the Department of Agriculture to assist SCRIPT (South Coast Regional Initiative Planning Team) in preparing the regional strategy. It records the key natural resource management issues threatening agricultural land on the south coast of Western Australia. Managing agricultural land effectively should be a priority in reducing the risks of land degradation on all assets-productive agricultural land, biodiversity and waterways.


Upper Yilgarn Catchment Appraisal 2005, Keith Ohlsen, Susan Murphy-White Jan 2005

Upper Yilgarn Catchment Appraisal 2005, Keith Ohlsen, Susan Murphy-White

Resource management technical reports

Soil degradation on farmland reduces agricultural production and will often lead to damage to natural resources such as remnant vegetation and waterways, as well as to infrastructure, including roads and townsites. This report provides current information on the land degradation status for the Upper Yilgarn Catchment area in Western Australia by outlining: condition of the soils, hydrology, natural vegetation, farming systems and agricultural production and risks to natural resources.


Effects Of Fire On Home Range Size, Site Fidelity And Habitat Associations Of Grassland Birds Overwintering In Southeast Texas, Heather Quebedeaux Baldwin Jan 2005

Effects Of Fire On Home Range Size, Site Fidelity And Habitat Associations Of Grassland Birds Overwintering In Southeast Texas, Heather Quebedeaux Baldwin

LSU Master's Theses

Understanding habitat affinities of wintering grassland birds is pertinent to their conservation. The objectives of this study were to evaluate the 1) effect burn history has on vegetation structure in coastal prairie; 2) habitat associations of the most common avian species; and, 3) home range size and site fidelity of Le Conte's Sparrow (LCSP). Data were collected on sites with 1-, 2- and 3-year burn histories during the winter of 2002 at Brazoria National Wildlife Refuge, Texas. Line transects were conducted to estimate bird abundance and vegetation measurements were recorded for herbaceous density, shrub density, and community type. Twenty-six Le …


Comparison Of Nicarbazin Absorption In Chickens, Mallards, And Canada Geese, C. A. Yoder, L. A. Miller, K. S. Bynum Jan 2005

Comparison Of Nicarbazin Absorption In Chickens, Mallards, And Canada Geese, C. A. Yoder, L. A. Miller, K. S. Bynum

United States Department of Agriculture Wildlife Services: Staff Publications

Nicarbazin (NCZ), a coccidiostat commonly used in the poultry industry, causes reduced hatchability and egg quality in layer hens at a concentration of 125 ppm (8.4 mg/kg) in the feed. Although this effect is undesirable in the poultry industry, NCZ could provide a useful wildlife contraception tool for waterfowl, particularly urban geese. We tested the absorption of NCZ in chickens (Gallus gallus), mallards (Anas platyrhynchos), and Canada geese (Branta canadensis) gavaged with 8.4 mg of NCZ/kg per bird each day for 8 d. Plasma levels of 4,4′-dinitrocarbanilide (DNC) differed significantly among species. Peak plasma …


A Comparison Of Three Trap Designs For Capturing Brown Treesnakes On Guam, Daniel S. Vice, Richard M. Engeman, Diane L. Vice Jan 2005

A Comparison Of Three Trap Designs For Capturing Brown Treesnakes On Guam, Daniel S. Vice, Richard M. Engeman, Diane L. Vice

United States Department of Agriculture Wildlife Services: Staff Publications

The accidental introduction of the brown treesnake (Boiga irregularis) to Guam has resulted in the extirpation of most native terrestrial vertebrates on the island, thousands of power outages, and significant ecological changes. In addition, Guam now serves as a source population for the dispersal of snakes to other islands. Control of the brown treesnake is dependent upon the use of traps in a variety of settings, including port environments and in forested habitat A variety of snake traps have been used on Guam; most consist of a modified crawfish or minnow trap, housing a live mouse that serves as a …


Potential Consequences Of The Coqui Frog Invasion In Hawaii, Karen H. Beard, William C. Pitt Jan 2005

Potential Consequences Of The Coqui Frog Invasion In Hawaii, Karen H. Beard, William C. Pitt

United States Department of Agriculture Wildlife Services: Staff Publications

The Puerto Rican frog, Eleutherodactylus coqui , has invaded Hawaii and has negatively impacted the state’s multimillion dollar floriculture, nursery and tourist industries; however, little is known about the ecological consequences of the invasion. Using data from Puerto Rico and Hawaii, the authors summarize the potential consequences of the invasion and describe future research needs. It could be predicted that the coqui would reduce the abundance of Hawaii’s endemic invertebrates. However, data suggest that coquis are mostly consuming non-native invertebrates, and not invertebrate pests, such as mosquitoes and termites. Endemic invertebrates are likely to represent a portion of the coqui …


Broad-Scale Non-Indigenous Species Monitoring Along The West Coast In National Marine Sanctuaries And National Estuarine Research Reserves, Catherine E. De Rivera, Greg Ruiz, Jeff Crooks, Kerstin Wasson, Steve Lonhart, Paul Fofonoff, Brian Steves, Steven S. Rumrill, Mary Sue Brancato, Scott Pegau, Doug Bulthuis, Rikke Kvist Preisler, Carl Schoch, Ed Bowlby, Andrew Devogelaere, Maurice Crawford, Steve Gittings, Anson Hines, Lynn Takata, Kristen Larson, Tami Huber, Anne Marie Leyman, Esther Collinetti, Tiffany Pascot, Suzanne Shull, Mary Anderson, Sue Powell Jan 2005

Broad-Scale Non-Indigenous Species Monitoring Along The West Coast In National Marine Sanctuaries And National Estuarine Research Reserves, Catherine E. De Rivera, Greg Ruiz, Jeff Crooks, Kerstin Wasson, Steve Lonhart, Paul Fofonoff, Brian Steves, Steven S. Rumrill, Mary Sue Brancato, Scott Pegau, Doug Bulthuis, Rikke Kvist Preisler, Carl Schoch, Ed Bowlby, Andrew Devogelaere, Maurice Crawford, Steve Gittings, Anson Hines, Lynn Takata, Kristen Larson, Tami Huber, Anne Marie Leyman, Esther Collinetti, Tiffany Pascot, Suzanne Shull, Mary Anderson, Sue Powell

Environmental Science and Management Faculty Publications and Presentations

Nonindigenous species have caused substantial environmental and economic damage to coastal areas. Moreover, the extent and impacts of nonindigenous species are increasing over time. To develop predictive models and to identify which areas should be targeted for impact mitigation or early detection, we need a basic foundation of knowledge about the spatial and temporal patterns of invasions. This project was developed because we lacked the necessary data to rigorously evaluate the patterns of coastal invasions. This collaborative project, between the Smithsonian Environmental Research Center, the National Estuarine Research Reserve System (NERRS) and the National Marine Sanctuary Program (NMSP), established a …


"An Investigation Into The Potential Of Immobilized Nitrifies In Wastewater Treatment", Ahmed S. Embaby Jan 2005

"An Investigation Into The Potential Of Immobilized Nitrifies In Wastewater Treatment", Ahmed S. Embaby

Theses

Removal of ammonia from wastewater is one of the problematic issues in wastewater treatment because nitrifies are very slow growing and can be washed out from activated sludge processes. There is a need to use higher advanced techniques to retain biomass. Among these techniques is cell immobilization in appropriate reactor environments. Cell immobilization technology can be approached by various methods, including cell entrapment or biofilms. However, these immobilization techniques are often accompanied by challenges in terms of biomass activity preservation and recovery following the immobilization treatment, reduction of nutrients mass transfer rates, adequate performance under shock situations and preservation of …


Effects Of Food Sources And Culture Conditions On Feeding Behaviour And Growth Rates Of Nile Tilapia Fry (Oreochromis Niloticus), Latifa Juma Rashid Al-Shamsi Jan 2005

Effects Of Food Sources And Culture Conditions On Feeding Behaviour And Growth Rates Of Nile Tilapia Fry (Oreochromis Niloticus), Latifa Juma Rashid Al-Shamsi

Theses

The importance of fish aquaculture in general as an alternative source of animal protein, is raised during this century after the significant reduction of natural marine resources. Such reduction has increased the interest of many countries as well as international agencies in worldwide food security, especially for developing countries. The success of any aquaculture is chiefly judged by its economic development, which always depends on the management of producing acceptable marketing size and weight of fish in short time. In the last few decades, many aquacultures failed in balancing between the financial input and the resultant income. That is due …


Seasonal Space Use, Habitat Preference And Survival Of Female Wild Turkeys In A Louisiana Bottomland Hardwood Forest, Walker Blake Wilson Jan 2005

Seasonal Space Use, Habitat Preference And Survival Of Female Wild Turkeys In A Louisiana Bottomland Hardwood Forest, Walker Blake Wilson

LSU Master's Theses

Female wild turkeys (Meleagris gallopavo) were captured and radio-marked in a bottomland hardwood forest in south-central Louisiana. Turkeys were monitored using radio telemetry from fixed points on Sherburne Wildlife Management Area, Atchafalaya National Wildlife Refuge, and Bayou des Ourses to observe seasonal patterns of space use, habitat preference and survival from 2002-04. The largest mean seasonal home range of 902.87 ha occurred during preincubation (15 Feb – 9 Apr; n = 24) when females typically search for suitable nest sites, and the smallest mean seasonal home range was 434.12 ha, during brood-rearing (1 Jun – 30 Sep; n = 32) …


Globalization, Ecological Security, And The Sustainability Of Human Societies, Mimi Larsen Becker Jan 2005

Globalization, Ecological Security, And The Sustainability Of Human Societies, Mimi Larsen Becker

The University Dialogue

No abstract provided.


Key Grazing Levels (Foo Targets) For Pasture And Sheep Management, Department Of Agriculture, Western Australia Jan 2005

Key Grazing Levels (Foo Targets) For Pasture And Sheep Management, Department Of Agriculture, Western Australia

Animal production and livestock published reports

Food On Offer (FOO) is the amount of pasture in front of an animal, and is measured in kilograms Dry Matter per hectare. Managing pastures to key grazing levels - or FOO targets - can result in improved production of grazing systems in Mediterranean environments which are characterized by slow winter growth, peak spring growth and dry summers. These targets vary according to what production response is required.

This information sheet illustrates key target FOO for sheep grazing annual pastures during autumn and spring.


Department Of Fisheries Annual Report To Parliament 2004/05, Government Of Western Australia Department Of Fisheries Jan 2005

Department Of Fisheries Annual Report To Parliament 2004/05, Government Of Western Australia Department Of Fisheries

Department of Fisheries Annual Reports

In accordance with Section 62 of the Financial Administration and Audit Act 1985 (FAAA) and Section 263 of the Fish Resources Management Act 1994 (FRMA), I submit for your information the Annual Report to Parliament of the Department of Fisheries of Western Australia for the financial year ending 30 June 2005.

The 2004/05 financial year has seen some important shifts in the external environment that bear on the economic viability of our major commercial fisheries and fishing-based tourism. But there has also been major progress within the Department on a number of significant issues - both strategic and operational - …


Maternal Yolk Steroids: A Potential Compensatory Mechanism For Red-Winged Blackbirds (Agelaius Phoeniceus) In North Dakota, Rachel M. Bush, Mark E. Clark, Wendy L. Reed, George M. Linz Jan 2005

Maternal Yolk Steroids: A Potential Compensatory Mechanism For Red-Winged Blackbirds (Agelaius Phoeniceus) In North Dakota, Rachel M. Bush, Mark E. Clark, Wendy L. Reed, George M. Linz

United States Department of Agriculture Wildlife Services: Staff Publications

Many of the suggested management techniques directed at reducing blackbird breeding populations fail to incorporate the underlying mechanisms regulating populations. Theoretically, removal of individuals from the breeding population should lower the breeding densities and presumably reduce recruitment. However, compensatory responses might occur with decreased breeding densities, but no empirical data are available to test this hypothesis. Much of the underlying compensatory theory is based on differential allocation of resources to reproduction vs. self maintenance at different breeding densities, mainly in the form of depensatory effects of resource limitation on growth and survival. However, as the breeding density in an area …


Blackbird Use And Damage Of Wildlife Conservation Sunflower Plots, Jonathan M. Raetzman, George M. Linz, William J. Bleier Jan 2005

Blackbird Use And Damage Of Wildlife Conservation Sunflower Plots, Jonathan M. Raetzman, George M. Linz, William J. Bleier

United States Department of Agriculture Wildlife Services: Staff Publications

Annual blackbird damage to sunflower is valued at $5 to $10 million. Perhaps more importantly, the National Sunflower Association has identified blackbirds as the key reason for growers to abandon sunflower in areas of prime production. North Dakota and South Dakota together produce approximately 70% of sunflower grown in the United States. This crop adds $906 million to the regional economy. To date, cost effective and environmentally safe methods to reduce bird damage to sunflower remain elusive. In the 1980’s, scientists from the National Wildlife Research Center (NWRC) showed that “decoy” sunflower plots can greatly reduce bird damage to local …


Wildlife Disease Research At The Aphis National Wildlife Research Center, R. G. Mclean, L. Clark, M. R. Dunbar, K. C. Vercauteren, T. A. Campbell Jan 2005

Wildlife Disease Research At The Aphis National Wildlife Research Center, R. G. Mclean, L. Clark, M. R. Dunbar, K. C. Vercauteren, T. A. Campbell

United States Department of Agriculture Wildlife Services: Staff Publications

Research on wildlife diseases at the newly formed Wildlife Disease Program (WDP) at the United States Department of Agriculture (USDA), Animal and Plant Health Inspection Service (APHIS), Wildlife Services (WS), National Wildlife Research Center (NWRC) concentrates on wildlife diseases of importance to domestic animal and human health. We are conducting studies on wildlife rabies, bovine tuberculosis (TB), chronic wasting disease (CWD), West Nile virus (WNV), pathogenic bacteria of birds, and pseudorabies (PR). The goal of the research is to develop innovative methods for surveillance, intervention, prevention, and control of these diseases.


Historic And Current Status Of The American White Pelican Breeding At Chase Lake National Wildlife Refuge, North Dakota, Marsha A. Sovada, D. Tommy King, Michael Erickson, Cheryl Gray Jan 2005

Historic And Current Status Of The American White Pelican Breeding At Chase Lake National Wildlife Refuge, North Dakota, Marsha A. Sovada, D. Tommy King, Michael Erickson, Cheryl Gray

United States Department of Agriculture Wildlife Services: Staff Publications

Chase Lake National Wildlife Refuge currently supports the largest breeding colony of the American White Pelican ( Pelecanus erythrorhynchos ) in North America. The first written account of the colony’s status was in 1905, when approximately 500 pelicans nested on two islands in Chase Lake. The colony grew to nearly 34,000 breeding birds by 2002. Surveys of breeding pelicans in the colony were sporadic from 1905 until 1972. Because the availability of foraging areas affects recruitment, pond counts from south-central North Dakota were used as an index of the relative availability of foraging areas. Pond counts varied widely in the …


Interactions Between The American White Pelican And Aquaculture In The Southeastern United States: An Overview, D. Tommy King Jan 2005

Interactions Between The American White Pelican And Aquaculture In The Southeastern United States: An Overview, D. Tommy King

United States Department of Agriculture Wildlife Services: Staff Publications

The eastern metapopulation of the American White Pelican ( Pelecanus erythrorhynchos ) breeds mainly in the Northern Great Plains, migrates through the Great Plains and along the Mississippi River and winters in the lower Mississippi River Valley and along the Gulf of Mexico. The production of farm-raised Channel Catfish ( Ictalurus punctatus ) in the southeastern United States has increased dramatically in the last 25 years. In 1990, U.S. Department of Agriculture Wildlife Services offices in Arkansas, Louisiana and Mississippi began receiving complaints concerning the foraging of pelicans in commercial Channel Catfish ponds. Because of the relatively shallow depth and …


Recent Population Status Of The American White Pelican: A Continental Perspective, D. Tommy King, Daniel W. Anderson Jan 2005

Recent Population Status Of The American White Pelican: A Continental Perspective, D. Tommy King, Daniel W. Anderson

United States Department of Agriculture Wildlife Services: Staff Publications

Breeding bird surveys were conducted at most American White Pelican ( Pelecanus erythrorhynchos ) colonies in North America from 1979-81 and the number of American White Pelicans was estimated at >109,000 breeding individuals in 55 colonies. Although many pelican colonies have not been surveyed since the early 1980s, we present the most current survey numbers available for North American colonies. Using available data (1998-2001) and the North American Continental Divide to delineate eastern from western metapopulations, 27 colonies and 48,240 nests in the East and 15 colonies and 18,790 nests in the West were documented, giving a total of about …


Introduction: Biology And Conservation Of The American White Pelican, Daniel W. Anderson, D. Tommy King Jan 2005

Introduction: Biology And Conservation Of The American White Pelican, Daniel W. Anderson, D. Tommy King

United States Department of Agriculture Wildlife Services: Staff Publications

Two separate, large-scale management units for the American White Pelican ( Pelecanus erythrorhynchos ) in North America are proposed: the eastern and western metapopulations, separated by the North American Continental Divide. The populations on either side of this barrier are subject to contrasting ecological conditions, movement patterns suggest strong geographic separation and each is likely demographically distinct. Subdivisions within these demographic units need to be more precisely defined in the future. Yet, because of the highly colonial nesting habits of the American White Pelican, conservation can still be effective if directed toward separate breeding colonies. Our intent is to provide …


Developing Relative Abundance Techniques (Rats) For Monitoring Rodent Populations, Desely A. Whisson, Richard M. Engeman, Kellie Collins Jan 2005

Developing Relative Abundance Techniques (Rats) For Monitoring Rodent Populations, Desely A. Whisson, Richard M. Engeman, Kellie Collins

United States Department of Agriculture Wildlife Services: Staff Publications

Accurate density estimates of rodents are frequently difficult or cost-prohibitive to determine. Thus, a number of techniques (track plates, monitoring blocks, chew cards/sticks, apple slice index, trapping) are often used to index rodent populations. Theoretically, the sensitivity of these indexing techniques could be improved if they applied continuous measurements rather than simple binary measurements (presence/absence). Development of a relative abundance technique that is simple to apply and sensitive to changes in population density is critical for the operational management of rodent pests. In addition to providing a quantitative measure of abundance with statistical parameters, an indexing technique that does not …


The Impact Of Disease In The American White Pelican In North America, Tonie Rocke, Kathryn Converse, Carol Meteyer, Bob Mclean Jan 2005

The Impact Of Disease In The American White Pelican In North America, Tonie Rocke, Kathryn Converse, Carol Meteyer, Bob Mclean

United States Department of Agriculture Wildlife Services: Staff Publications

Records of reported die-offs of the American White Pelican ( Pelicanus erythrorhynchos ) held by the U.S. Geological Survey National Wildlife Health Center from 1978 through 2003 indicate that type C botulism (caused by Clostridium botulinum ) was the major cause of mortality. In 1996, over 15,000 birds, including 8,500 American White Pelicans, were estimated to have died from type C botulism at the Salton Sea in California. This was the largest documented die-off of any pelican species and was estimated to represent 15-20% of the western metapopulation. This event was also notable in that it was the first time …


Husbandry Of Wild-Caught Greater Sage-Grouse, Paul Oesterle, Robert Mclean, Michael Dunbar, Larry Clark Jan 2005

Husbandry Of Wild-Caught Greater Sage-Grouse, Paul Oesterle, Robert Mclean, Michael Dunbar, Larry Clark

United States Department of Agriculture Wildlife Services: Staff Publications

This study reports the first successful husbandry and breeding in captivity of wild-caught greater sage-grouse (Ccntroccrcus urophasianus). In October 2003, 2 1 hatch-year greater sage-grouse were trapped in northwestern Nevada and transported to Fort Collins, Colorado. We held grouse in pens at the United States Department of Agriculture's National Wildlife Research Center for 8 months. We offered a varied diet, including native food items such as sagebrush (Arternisia tridentata and A. tripartita) and yarrow (Achilles millefolium). We housed grouse in a large flight pen and allowed to them freerange as one flock. Mortdlity rate was 16.7%. Several of the grouse …


From The Field: Field Searches Versus Vaginal Implant Translocating Elk Calves, Nathan W. Seward, David S. Maehr, Jonathan W. Gassett, John J. Cox, Jeffrey L. Larkin Jan 2005

From The Field: Field Searches Versus Vaginal Implant Translocating Elk Calves, Nathan W. Seward, David S. Maehr, Jonathan W. Gassett, John J. Cox, Jeffrey L. Larkin

United States Department of Agriculture Wildlife Services: Staff Publications

We compared the utility of vaginal implant transmitters (VITs) and field searches for locating elk (Cervus elaphus) calves in southeastern Kentucky during the spring of 2001. Retention of VITs among 40 adult females ranged from 1–276 days (x - =61.6±8.4 [SE] days). Approximately half of the transmitters (n=19) were expelled prematurely or malfunctioned. Two of 37 (5%) transmitters in translocated females performed as designed and led to calf capture. We captured more calves (n=9 in 2001; n=16 in 2002) by searching areas where elk exhibited parturition behavior. We suggest that manufacturers refine the current VIT design to increase its application …


West Nile Virus Infection In Farmed American Alligators (Alligator Mississippiensis) In Florida, Elliott R. Jacobson, Pamela E. Ginn, J. Mitchell Troutman, Lisa Farina, Lillian Stark, Kaci Klenk, Kristen L. Burkhalter, Nicholas Komar Jan 2005

West Nile Virus Infection In Farmed American Alligators (Alligator Mississippiensis) In Florida, Elliott R. Jacobson, Pamela E. Ginn, J. Mitchell Troutman, Lisa Farina, Lillian Stark, Kaci Klenk, Kristen L. Burkhalter, Nicholas Komar

United States Department of Agriculture Wildlife Services: Staff Publications

No abstract provided.


High Dispersal In A Frog Species Suggest That It Is Vulnerable To Habitat Fragmentation, W. Chris Funk, Allison E. Greene, Paul Stephen Corn, Fred W. Allendorf Jan 2005

High Dispersal In A Frog Species Suggest That It Is Vulnerable To Habitat Fragmentation, W. Chris Funk, Allison E. Greene, Paul Stephen Corn, Fred W. Allendorf

United States Geological Survey: Staff Publications

Global losses of amphibian populations are a major conservation concern and have generated substantial debate over their causes. Habitat fragmentation is considered one important cause of amphibian decline. However, if fragmentation is to be invoked as a mechanism of amphibian decline, it must first be established that dispersal is prevalent among contiguous amphibian populations using formal movement estimators. In contrast, if dispersal is naturally low in amphibians, fragmentation can be disregarded as a cause of amphibian declines and conservation efforts can be focused elsewhere. We examined dispersal rates in Columbia spotted frogs (Rana luteiventris) using capture– recapture analysis …


Population Structure Of Columbia Spotted Frogs (Rana Luteiventris) Is Strongly Affected By The Landscape, W. Chris Funk, Michael S. Blouin, Paul Stephen Corn, Bryce A. Maxell, David S. Pilliod, Stephen Amish, Fred W. Allendorf Jan 2005

Population Structure Of Columbia Spotted Frogs (Rana Luteiventris) Is Strongly Affected By The Landscape, W. Chris Funk, Michael S. Blouin, Paul Stephen Corn, Bryce A. Maxell, David S. Pilliod, Stephen Amish, Fred W. Allendorf

United States Geological Survey: Staff Publications

Landscape features such as mountains, rivers, and ecological gradients may strongly affect patterns of dispersal and gene flow among populations and thereby shape population dynamics and evolutionary trajectories. The landscape may have a particularly strong effect on patterns of dispersal and gene flow in amphibians because amphibians are thought to have poor dispersal abilities. We examined genetic variation at six microsatellite loci in Columbia spotted frogs (Rana luteiventris) from 28 breeding ponds in western Montana and Idaho, USA, in order to investigate the effects of landscape structure on patterns of gene flow. We were particularly interested in addressing …


Population Dynamics Of Oryzomys Palustris And Microtus Pennsylvanicus In Virginia Tidal Marshes, Christopher P. Bloch, Robert K. Rose Jan 2005

Population Dynamics Of Oryzomys Palustris And Microtus Pennsylvanicus In Virginia Tidal Marshes, Christopher P. Bloch, Robert K. Rose

Biological Sciences Faculty Publications

Oryzomys palustris (marsh rice rat) and Microtus pennsylvanicus (meadow vole) cohabit coastal marshes in the mid-Atlantic US. Both were live-trapped for 23 months at two tidal marsh sites in Virginia to assess their demography near the margins of their distributions. In the presence of dense vegetation, population dynamics of the two species were seasonal and positively correlated, with densities declining through the winter. At the more sparsely vegetated site, densities of both species were lower, and densities of M. pennsylvanicus were negatively correlated with those of O. palustris. Patterns of reproduction differed between the species. O. palustris was reproductively …


Identification Of Shiga Toxin-Producing Escherichia Coli In The Uae, Khawla Hamad Mohd Al-Areef Al-Dhaheri Jan 2005

Identification Of Shiga Toxin-Producing Escherichia Coli In The Uae, Khawla Hamad Mohd Al-Areef Al-Dhaheri

Theses

Identification of Shiga Toxin-Producing Escherichia coli in the UAE

By

Khawla Hamad Mohd Al-Areef Al-Dhaheri

Abstract

Various patho-groups of Escherichia coli strains are important causes of diarrheal diseases worldwide. Among these strains Shiga toxin producing isolates are particularly important. They are carried by various animals and upon infection, in humans, they may cause serious bloody diarrhea, and in some cases even life threatening sequels as hemolytic uremic syndrome. However, these infections are often under-diagnosed due to the fact that pathogenic strains do not differ from their nonpathogenic counterparts in characters investigated by standard microbiological techniques. Consequently, they can only be …