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The Physiology Of Life History Trade-Offs In Animals, Anthony J. Zera, Lawrence G. Harshman

Anthony Zera Publications

The functional causes of life history trade-offs have been a topic of interest to evolutionary biologists for over six decades. Our review of life history trade-offs discusses conceptual issues associated with physiological aspects of trade-offs, and it describes recent advances on this topic. We focus on studies of four model systems: wing polymorphic insects, Drosophila, lizards, and birds. The most significant recent advances have been: (a) incorporation of genetics in physiological studies of trade-offs, (b) integration of investigations of nutrient input with nutrient allocation, (c) development of more sophisticated models of resource acquisition and allocation, (d) a shift to more …

Invasion Genetics Of New World Medflies: Testing Alternative Colonization Scenarios, Andrew J. Bohonak, Neil Davies, Francis X. Villablanca, George K. Roderick

Biological Sciences

The Mediterranean fruit fly (Ceratitis capitata) is an invasive agricultural pest with a wide host range and a nearly global distribution. Efforts to forgo the medfly''s spread into the United States are dependent on an understanding of population dynamics in newly established populations elsewhere. To explore the potential influence of demographic and historical parameters in six medfly populations distributed from Mexico to Peru, we created population genetic null models using Monte Carlo simulations. Null expectations for genetic differentiation (F _ST) were compared with actual sequence variation from four highly polymorphic nuclear loci. Four colonization scenarios that …

Biodiversity: The World Of Life, Charles H. Smith

DLPS Faculty Publications

No abstract provided.

Phylogenetic Relationships, Taxonomy, And Evolution Of Host Choice In Diadasia (Hymenoptera: Apoidea), Sedonia D. Sipes

Biology

I examined the phylogenetic relationships, taxonomy, and evolution of host choice in Diadasia, a genus of New World bees. Diadasia species are particularly interesting because they are considered pollen specialists. Females of each species are believed to provision their nests with pollen from only a few closely related plant taxa. At the same time, the choice of floral hosts within the genus is diverse, and includes five distantly related plant families: Malvaceae, Onagraceae, Convolvulaceae, Asteraceae, and Cactaceae. To estimate phylogenetic relationships within this group, I sequenced ~ 2 kb of the mitochondrial genes CO I and II and tRNA …

Morphometric Evaluation Of The Whitefish Complex In Bear Lake, Utah/Idaho, Alan Ward

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Whitefish populations around the world have long been difficult to categorize taxonomically. The whitefish of Bear Lake, Utah/Idaho are no exception. There are three recognized species of Prosopium that are endemic to the lake. Two of these species, Prosopium spilonotus and Prosopium abyssicota, have previously been indistinguishable outside of spawning times. Previous studies have proposed additional taxa within P. spi/onotus to further complicate the identification among these taxa.

Morphological characteristics were quantified on wild whitefish from Bear Lake, as well as from progeny reared in the laboratory from the wild adult fish. The purported taxa were separated in the field …

Comparison Of Rodent Communities Of Native Brushland, Replanted, And Secondary Succession Sites In The Lower Rio Grande Valley Of Texas, Mitchell Allen Sternberg

Theses and Dissertations - UTB/UTPA

I compared small mammal communities between mature brushlands, replanted brushlands, and secondary succession sites from November 1998 to December 1999 to evaluate revegetation efforts in the Lower Rio Grande Valley of Texas. I determined rodent community characteristics of the three habitat types. The mature brushland and replanted habitats had similar species diversities and both were significantly higher than the secondary succession habitat. Species diversity was highest at the replanted edge grid during Winter. The current replanting method provides a more diverse rodent community than does natural succession from fallow fields. Wildlife monitoring should be extended to other taxonomic guilds so …

American Society Of Parasitologists Newsletter, V. 23, No. 1, January 2001, Scott Lyell Gardner

American Society of Parasitologists: Newsletter

An issue of the American Society of Parasitologists' quarterly newsletter, also called the Journal of Parasitology Newsletter.

Treefall Gaps And The Maintenance Of Species Diversity In A Tropical Forest, Stefan A. Schnitzer, Walter P. Carson

Biological Sciences Faculty Research and Publications

The maintenance of species diversity by treefall gaps is a long‐standing paradigm in forest ecology. Gaps are presumed to provide an environment in which tree species of differing competitive abilities partition heterogeneous resources. The empirical evidence to support this paradigm, however, remains scarce, and some recent studies even suggest that gaps do not maintain the diversity of shade‐tolerant species. Although there is evidence that gaps maintain the diversity of pioneer trees, most of this evidence comes from studies that did not make comparisons between gaps and intact forest sites (controls). Further, nearly all studies on the maintenance of diversity by …

The Effect Of Nitrogen Fertilization On Short-Term Fine Root Dynamics In A Barrier Island Dune Community, John Walter Hutton

Biological Sciences Theses & Dissertations

Fine root dynamics are an important yet poorly understood component of terrestrial ecosystems. In recent years a number of researchers have focused on fine root dynamics; their work has looked at patterns across one or multiple growing seasons on a scale of monthly measures. The purpose of this study was to add to the overall understanding by looking at fine root dynamics on a shorter temporal scale. Minirhizotron observation tubes were used to assess the effect of nitrogen fertilization on short-term fine root dynamics in a nutrient limited, barrier island dune system. Root length elongation and mortality rates followed expected …

Preliminary Checklist Of The Orthopteroid Insects (Blattodea, Mantodea, Phasmatodea,Orthoptera) Of Texas, John A. Stidham, Thomas A. Stidham

Insecta Mundi

Texas has one of the most diverse orthopteroid assemblages of any state in the United States, reflecting the varied habitats found in the state. Three hundred and eighty-nine species and 78 subspecies of orthopteroid insects (Blattodea, Mantodea, Phasmatodea, and Orthoptera) have published records for the state of Texas. This is the first such comprehensive checklist for Texas and should aid future work on these groups in this area.

Wpa News 64 (2001), World Pheasant Association

Galliformes Specialist Group and Affiliated Societies: Newsletters

WPA News (February 2001), number 64

Published by the World Pheasant Association

Development, Testing, And Implementation Of The Temple-Inland, Inc. Sustainable Forest Management System (Tinsms), 2001, Arthur Temple College Of Forestry And Agriculture

eBooks

No abstract provided.

Managing Minnesota's Recovered Wolves, L. David Mech

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

The Minnesota wolf (Canis lupus) population was estimated by the Minnesota Department of Natural Resources at 2,450 during winter 1997-1998 and had increased at an average annual rate of 4.5°% since winter 1988-1989. The population may be removed from the federal endangered species list by 2002, and management would then return to the state. A federal recovery team recommended a population goal of 1,250-1,400 wolves for Minnesota, with none in the agricultural region. A plan approved by the Minnesota legislature, however, continues the protection of wolves, except for pet and livestock depredation control, for at least 5 years …

The Gray Wolves (Canis Lupus) Of British Columbia’S Coastal Rainforests, Chris T. Darimont, Paul C. Paquet

Biogeography and Ecological Opportunity Collection

The mainland coast of British Columbia (BC) is a remote area that is comparatively free from human-caused disturbance. However, concerns about current and anticipated increases in industrial forestry activity have prompted conservation biologists to investigate the biota in this understudied region. We were commissioned by the Raincoast Conservation Society to study coastal wolves so that information could be incorporated into ongoing conservation planning and education efforts. The summer of 2000 marked the pilot season of a multi-year research project. Our team spent more than 240 person days in the field during the summer and fall seasons. We surveyed 18 mainland …

Counting Cranes: How Much Effort Is Enough?, Douglas H. Johnson, Roderick C. Drewien, Douglas S. Benning

Proceedings of the North American Crane Workshop

Accurate population estimates of sandhill cranes (Grus canadensis) are important because management decisions, such as establishing hunting regulations, are based on those estimates. Counts often are made during aerial surveys when the cranes are congregated. A complete census may be feasible if the area to be surveyed is small and adequate resources are available. For large areas, resources may be inadequate for a census so partial counts (sample surveys) are made. Because cranes are gregarious, the counts in a sample of units may contain either a disproportionately large, or a disproportionately small, fraction of the total, leading to …

Nocturnal Roost Site Selection And Diurnal Habitat Use By Sandhill Cranes During Spring In Central Nebraska, Craig A. Davis

Proceedings of the North American Crane Workshop

During spring 1998 and 1999, the Platte River Whooping Crane Maintenance Trust conducted ground and aerial surveys of staging sandhill cranes (Grus canadensis; hereafter, cranes) to detennine roost site selection and habitat-use patterns along a l20-Ian stretch of the Platte River in south-central Nebraska. Cranes peaked at 232,023 during 22-28 March 1998 and 206,074 during 28 Februaty-6 March 1999 in the study area, a portion of the total crane staging area in the Platte River Valley. Diurnal observations showed that 48% of the cranes were in com fields, 34% in lowland grasslands, 13% in alfalfa fields, and 5% …

Crop Watch No. 2001-19, August 3, 2001, Lisa Brown Jasa

Crop Watch (1994–2005)

Field Updates..........168

Western Nebraska Insects..........170

Western Wheat Yields..........171

Preventing Wheat Diseases..........171

Bacterial Stalk Rot in Corn..........172

Soybean Field Days..........173

2nd ECB Flight..........174

Planting Alfalfa..........174

Terminating Farm Leases..........175

Wright's Research Areas..........176

Forage Options..........176

The Evolution Of Virtual Ecology, Alan Kamil, Alan B. Bond

Alan Bond Publications

The relationship between the perceptual and cognitive abilities of predatory birds and the appearance of their insect prey has long been of intense interest to evolutionary biologists. One classic example is crypsis, the correspondence between the appearance of prey species and of the substrates on which they rest which has long been considered a prime illustration of effects of natural selection, in this case operating against individuals that were more readily detected by predators (Poulton 1890; Wallace 1891). But the influences of predator psychology are broader, more complex, and more subtle than just pattern matching. Many cryptic prey, including the …

Ecological Sustainability For Pastoral Management, Hugh Pringle, Ken Tinley

Journal of the Department of Agriculture, Western Australia, Series 4

Pastoralists and rangeland bureaucracies are now required to operate within the limits of ecological sustainability. However, while the concept of ecological sustainability has been enshrined in law and policy at State and Commonwealth levels in Australia, there has been little translation into pastoral management objectives. The introduction of the 'EMU (Ecosystem Management Unit) process', as an equal partnership between ecologists and pastoralists, promises to bring pastoralists into close dialogue with the landscapes they manage on their stations, and to acknowledge and manage for values other than pasture production. In doing so, pastoralists are likely to increase production, reduce costs, and …

Persistence Of Aspen Regeneration Near The National Elk Refuge And Gros Ventre Valley Elk Feedgrounds Of Wyoming, D.T. Barnett, T.J. Stohlgren

Aspen Bibliography

We investigated aspen (Populus tremuloides) regeneration in the Gros Ventre River Valley, the National Elk Refuge, and a small part of Grand Teton National Park, Wyoming, to see if elk (Cervus elaphus) browsing was as damaging as previously thought. We conducted a landscape-scale survey to assess aspen regeneration across gradients of wintering elk concentrations using 68 randomly selected aspen stands in the 1,090 km2 study area. Forty-four percent of the stands sampled supported regeneration of saplings (stems greater than 2 m in height but less than 10 cm in diameter). There were no significant differences of regeneration across elk winter …

Long-Term Aspen Exclosures In The Yellowstone Ecosystem, Charles E. Kay

Aspen Bibliography

Aspen has been declining in the Yellowstone Ecosystem for more than 80 years. Some authors have suggested that aspen is a marginal plant community in Yellowstone and that recent climatic variation has adversely affected aspen, while others contend that excessive browsing by native ungulates is primarily responsible for aspen’s widespread decline. To test these hypotheses, I measured all the long-term aspen exclosures (n = 14) in the Yellowstone Ecosystem. Aspen stands inside all exclosures successfully produced new stems greater than 2 m tall without fire or other disturbance, while few outside stands successfully regenerated due to repeated browsing. Understory species …

Effects Of High Dietary Protein And High Energy Density On Gastric Evacuation And Return Of Appetite In The Rainbow Trout, Oncorhynchus Mykiss, Ahmet Adem Teki̇nay, Yusuf Güner

Turkish Journal of Biology

Rainbow trout (Oncorhynchus mykiss) were fed diets containing three different concentrations of crude protein (56.3%, 51.7% and 45.8%) and digestible energy (21.3, 20.3 and 18.8 MJ/kg), and the effects of dietary protein and energy level on gastric evacuation and return of appetite times were investigated. Gastric evacuation determinations were achieved by slaughtering 8 fish every 6 hours until no residue was found in the cardiac stomach of fish. Return of appetite experiments were conducted by re-feeding groups of trout every 4 or 6 hours following the first feeding. The data obtained from each process was modelled by regression analysis and …

Life History Of The River Shiner, Notropis Blennius (Cyprinidae), In The Arkansas River Of Western Arkansas, Laura Hudson, Thomas M. Buchanan

Journal of the Arkansas Academy of Science

The reproductive cycle, food habits, and age and growth of the river shiner, Notropis blennius (Girard), in the Arkansas River of western Arkansas were studied from May 1996 through October 1997. Based on gonadosomatic indices and mean ovumd iameters of females, tubercle development in males, and the first appearance of young-of-year in samples, the breeding season extended from June through August in both 1996 and 1997. The river shiner is a diurnal, generalist feeder that forages on a wide variety of food items. In all four seasons, detritus dominated the diets of adults and juveniles in terms of volume and …

Distribution Of Leconte's Free-Tailed Bat (Tadarida Brasiliensis Cynocephala) In Arkansas, With Notes On Reproduction And Natural History, David A. Saugey, D. Blake Sasse, J. D. Wilhide, Drew Reed, Tammy R. Jones, Darrell R. Heath, Daniel R. England

Journal of the Arkansas Academy of Science

During the past 20 years (1982-2001) we have studied the biology, occurrence and distribution of LeConte's (Brazilian) free-tailed bat, Tadarida brasiliensis cynocephala, in Arkansas. Colonies and individuals were reported from man made structures only. Four new county records have been documented since 1988, extending the range from the central part of the state to Arkansas's northern-most tier of counties. Numerous nuisance maternity colonies were investigated during exclusion activities and one, year-round colony provided the majority of reproductive data. A total of 152 free-tailed bats was submitted to the Arkansas Department of Health Rabies Laboratory (1982-2001); most during February through April, …

Rhinocyllus Conicus: Initial Evaluation And Subsequent Ecological Impacts In North America, A. Gassmann, Svata M. Louda

School of Biological Sciences: Faculty Publications

Renewed debate over the risk of non-target effects in biological control reflects, in part, the recent quantification of direct and indirect ecological effects of the flowerhead weevil, Rhinocyllus conicus Frol., in North America. To help resolve the issue, we review the published data for R. conicus from both Europe and North America: pre-release (1961-1968), post-release (1969-1985) and more recent (1986-1999). Our aim was to determine the extent to which host range expansion on to native North American species, and the associated ecological effects, were predicted or predictable. Our overall conclusion is that more was known than is generally realized, yet …

Research Needs Concerning Non-Target Impacts Of Biological Control Introductions, K.R. Hopper

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

Two workshops were held in 1999 on research needs concerning non-target impacts of biological control introductions. One took place on the Internet for 9 months, and the other in Montpellier, France, for 1 day. Altogether, over 200 researchers from over 30 countries participated, representing a wide variety of viewpoints on the issues involved. The deliberations of these workshops are summarized here. Both workshops highlighted the need for retrospective studies to: (i) identify cases of significant non-target impacts; (ii) explore mechanisms involved when such impacts are found; (iii) evaluate the reliability of host-range testing protocols; and (iv) determine whether and under …

Effects Of Recording Media On Echolocation Data From Broadband Bat Detectors, Ethan P. White, S. D. Gehrt

Biology Faculty Publications

Bat detectors are an important tool for ecological studies of bats. However, the quality and quantity of data may be affected by the recording devices used to record the output from the detector. We compared recordings of bat activity from audiocassette recorders and computers. Numbers of calls/hour, passes/hour, identifiable passes/hour, and feeding buzzes/hour were similar (all P’s > 0.1) between recording devices. All call characteristics, except for the minimum frequency and characteristic frequency, differed (P < 0.05) between tapes and computers. Species identification with discriminate function analysis was less reliable with tape data than with computer data, particularly when the model built with computer-recorded reference calls was tested with tape-recorded calls. Therefore, we suggest when tape recorders are used for field recording that they also are used to record reference calls.

A Critical Evaluation Of Research Techniques In Animal Ecology, Michelle A. Baker

Biology Faculty Publications

No abstract provided.

Aspects Of The Taxonomy And Ecology Of The Ground Beetle (Coleoptera: Carabidae) Assemblage Of The Swan Coastal Plain : (With Particular Reference To Habitat Fragmentation And The Quindalup Dune System), Nadine A. Guthrie

Theses: Doctorates and Masters

Long term studies encompassing seasonal variation in abundance and species present, forming base-line phenological data, arc required to understand the responses of the carabid (Ground Beetle) fauna to major habitat changes. In addition, few habitats unaffected by human disturbance remain in Australia, and evaluation of these fauna in these areas is required before further habitat loss occurs. Generally an unknown group of terrestrial predatory invertebrates in Australia, carabids have been the subjects of few ecological studies in this country. This restricts the utility of the Carabidae in environmental or conservation assessment programs in Australia. A study was initiated to assess …

The Mayfly Newsletter, Peter M. Grant

The Mayfly Newsletter

The Mayfly Newsletter is the official newsletter of the Permanent Committee of the International Conferences on Ephemeroptera.