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Effects Of Targeted Grazing And Prescribed Burning On Fire Behavior And Community Dynamics Of A Cheatgrass (Bromus Tectorum)-Dominated Landscape, Joel M. Diamond May 2009

Effects Of Targeted Grazing And Prescribed Burning On Fire Behavior And Community Dynamics Of A Cheatgrass (Bromus Tectorum)-Dominated Landscape, Joel M. Diamond

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Studies were conducted to determine the effectiveness of using targeted grazing and prescribed burning as tools to reduce fire hazards and cheatgrass (Bromus tectorum) dominance on rangelands in the northern Great Basin. A field study, with four grazing-burning treatments (graze and no-burn, graze and burn, no-graze and burn, and no-graze and no-burn), was conducted on a B. tectorum-dominated site near McDermitt, Nevada from 2005-2007. Cattle removed 80-90% of standing biomass in grazed plots in May 2005 and 2006 when B. tectorum was in the boot (phenological) stage. Grazed and ungrazed plots were burned in October 2005 and …


The Ants Of South Carolina, Timothy Davis May 2009

The Ants Of South Carolina, Timothy Davis

All Dissertations

The ants of South Carolina were surveyed in the literature, museum, and field collections using pitfall traps. M. R. Smith was the last to survey ants in South Carolina on a statewide basis and published his list in 1934. VanPelt and Gentry conducted a survey of ants at the Savanna River Plant in the 1970's. This is the first update on the ants of South Carolina since that time.
A preliminary list of ants known to occur in South Carolina has been compiled. Ants were recently sampled on a statewide basis using pitfall traps. Two hundred and forty-three (243) transects …


Roosting And Foraging Ecology Of Forest Bats In The Southern Appalachian Mountains, Joy O'Keefe May 2009

Roosting And Foraging Ecology Of Forest Bats In The Southern Appalachian Mountains, Joy O'Keefe

All Dissertations

Although most bats in the southeastern United States depend on forests for roosting and foraging, we know little about the ecological requirements of bats that live in this region. The objective of this study was to use radio telemetry, acoustic sampling, Akaike's information theoretic procedures, occupancy modeling, and discriminant function analyses to: 1) examine multi-scale roost-site selection for three forest bat species [eastern pipistrelles (Perimyotis subflavus), eastern red bats (Lasiurus borealis), and northern long-eared bats (Myotis septentrionalis)], 2) test the effects of timber harvest on bat foraging ecology in riparian areas, and 3) compare and relate methods of assessing vegetative …


Comparative Genomics And Molecular Evolution: New Genomic Resources For The Hymenoptera And Evolutionary Studies On The Genes Of The Nasonia Vitripennis Hox Complex., Monica Munoz-Torres May 2009

Comparative Genomics And Molecular Evolution: New Genomic Resources For The Hymenoptera And Evolutionary Studies On The Genes Of The Nasonia Vitripennis Hox Complex., Monica Munoz-Torres

All Dissertations

Research on insects, the most successful group from all metazoans on earth, has important societal, as well as scientific benefits. Insects occupy a wide range of roles, which have an effect on human life either because the former pose serious threats to public health and commercial crops as well as in some cases represent the only way to propagate food resources. Despite their tremendous importance, insect genomics remained an uneven territory dominated by studies in the Drosophila group and the mosquitoes. This dissertation attempts to: 1) report on advances in the development and characterization of genomic tools for species of …


Consequences Of Vegetation Change On The Dynamics Of Labile Organic Matter And Soil Nitrogen Cycling In A Semiarid Ecosystem, Toby D. Hooker May 2009

Consequences Of Vegetation Change On The Dynamics Of Labile Organic Matter And Soil Nitrogen Cycling In A Semiarid Ecosystem, Toby D. Hooker

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Sagebrush-dominated ecosystems are being transformed by wildfire, rangeland improvement techniques, and exotic plant invasions. These disturbances have substantial effects on the composition and structure of native vegetation, but the effects on ecosystem C and N dynamics are poorly understood. To examine whether differences in dominant vegetation affect the quantity and quality of plant organic matter inputs to soil, ecosystem C and N pools and rates of plant turnover were compared among historically grazed Wyoming big sagebrush, introduced perennial crested wheatgrass, and invasive annual cheatgrass communities. Since low soil moisture during the summer may inhibit the microbial colonization of plant detrital …


Controls On Microbial Community Structure In Thermal Environments: Exploring Bacterial Diversity And The Relative Influence Of Geochemistry And Geography, Kendra Renee Mitchell May 2009

Controls On Microbial Community Structure In Thermal Environments: Exploring Bacterial Diversity And The Relative Influence Of Geochemistry And Geography, Kendra Renee Mitchell

Biology ETDs

Community wide molecular surveys have revealed incredible hidden phylogenetic and metabolic diversity in microbial habitats. We have conducted the first microbial survey of Yellowstone National Park thermal environments, sampling 103 communities from across the park and across the range of conditions found. Yellowstone is particularly suited for this type of research because of the large number and wide variety of thermal springs, which are naturally occurring chemostats enabling examination of the factors that control microbes and drive community structure. In addition to samples for molecular microbial analysis, we collected water for extensive geochemical analysis in order to begin to deduce …


Vegetation Characteristics Of Wyoming Big Sagebrush Communities Historically Seeded With Crested Wheatgrass In Northeastern Great Basin, Usa, Justin Rodney Williams May 2009

Vegetation Characteristics Of Wyoming Big Sagebrush Communities Historically Seeded With Crested Wheatgrass In Northeastern Great Basin, Usa, Justin Rodney Williams

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Crested wheatgrass (Agropyron cristatum [L.] Gaertn.) is one of the most commonly seeded grass species in the western United States and dominates thousands of hectares in the Great Basin. Although many degraded Wyoming big sagebrush (Artemisia tridentata ssp. wyomingensis) plant communities have been seeded with crested wheatgrass, successional pathways, influence of soil attributes, and cultivation history on the vegetation of these communities have not been fully characterized. I sought to identify community phases, vegetative differences, and soil attributes that explain variation among 35 Wyoming big sagebrush communities historically seeded with crested wheatgrass. All communities were more than …


Review Of The Natural History Of The Handsome Fungus Beetles (Coleoptera: Cucujoidea: Endomychidae), F. W. Shockley, K. W. Tomaszewska, J. V. Mchugh Apr 2009

Review Of The Natural History Of The Handsome Fungus Beetles (Coleoptera: Cucujoidea: Endomychidae), F. W. Shockley, K. W. Tomaszewska, J. V. Mchugh

Insecta Mundi

The literature pertaining to natural history of Endomychidae (Coleoptera: Cucujoidea) is reviewed. One hundred fungal host records are provided for 32 endomychid species. Twenty-three records of endomychid yeast endosymbionts are compiled. Summaries are also presented for feeding preferences, interactions with natural enemies, non-lethal symbiotic relationships, and pest activity within the family. Unusual endomychid behaviors and habitats are reviewed, with particular attention to gregariousness and defensive strategies within Endomychidae.


Differential Response Of Amp Activated Protein Kinase (Ampk) And Hsp70 To Temperature Stress In The Gastropod, Nucella Lapillus, Emily Zimmermann Apr 2009

Differential Response Of Amp Activated Protein Kinase (Ampk) And Hsp70 To Temperature Stress In The Gastropod, Nucella Lapillus, Emily Zimmermann

All Theses And Dissertations

Populations of the gastropod Nucella lapillus are polymorphic for shell color, with light-colored shells predominating on warmer, wave-protected shores and dark-colored shells limited primarily to cooler, wave-exposed shores. During thermal stress, darker shells attain higher body temperatures than lighter shells. These results suggest that heat stress may determine field distribution patterns. However, there is currently little evidence of physiological consequences of thermal stress in these organisms. Following the guiding hypothesis that heat stress leads to cellular energy depletion, we explored whether the central energy regulator AMP-activated Protein Kinase (AMPK) is activated by heat stress. We compared this response in both …


Miti Iko Wapi Ii ?, Taylor Tully Apr 2009

Miti Iko Wapi Ii ?, Taylor Tully

Independent Study Project (ISP) Collection

Vegetative communities within the savannah ecosystem oscillate between grassland and woodland states. Research has found that ecological perturbations resulting from elephants, fire, other herbivores and humans have a significant influence on the oscillation of vegetative communities. Understanding these forces and how they interplay to influence vegetative dynamics states is essential to a developing any effective conservation management program. A previous study, in 2003, was conducted to establish baseline data on vegetative community structure, elephant damage and fire damage within Ndarakwai Ranch. (Hamilton and Downing 2003). However, the study drew few definitive conclusions and suggested further research. This study was a …


Why Museums Matter: A Tale Of Pinworms (Oxyuroidea: Heteroxynematidae) Among Pikas (Ochotona Princeps And O. Collaris) In The American West [Critical Comment], Eric P. Hoberg, Patricia A. Pilitt, Kurt Galbreath Apr 2009

Why Museums Matter: A Tale Of Pinworms (Oxyuroidea: Heteroxynematidae) Among Pikas (Ochotona Princeps And O. Collaris) In The American West [Critical Comment], Eric P. Hoberg, Patricia A. Pilitt, Kurt Galbreath

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Permanent and well-supported museum or natural history collections provide a solid foundation for the process of systematics research through creation of an empirical record which validates our understanding of the biosphere. We explore the role of museums in ongoing studies of the complex helminth fauna characteristic of pikas (Ochotona spp.) in the American west. These studies address the taxonomy for pinworms of the Labiostomatinae and the problems associated with the absence of adequate type series and vouchers and with misidentifications in original descriptions. We demonstrate that the types for Labiostomum (Labiostomum) coloradensis are identical to some specimens …


Agricultural Research Division News – February/March 2009, Volume 41, Number 7 Mar 2009

Agricultural Research Division News – February/March 2009, Volume 41, Number 7

Agricultural Research Division: News and Annual Reports

Contents:
Comments from Dean Gary Cunningham
USDA Agriculture and Food Research Initiative (AFRI)
NIH Equipment Grants
ARD Funding Opportunities
ARD Summary of Graduate Student Enrollment - Fall 2008
New or Revised Projects (November and December 2008)
Proposals Submitted for Federal Grants (November and December 2008)
Grants and Contracts Received (November and December 2008)


From Cells To Coastlines: How Can We Use Physiology To Forecast The Impacts Of Climate Change?, Brian Helmuth Mar 2009

From Cells To Coastlines: How Can We Use Physiology To Forecast The Impacts Of Climate Change?, Brian Helmuth

Faculty Publications

The interdisciplinary fields of conservation physiology, macrophysiology, and mechanistic ecological forecasting have recently emerged as means of integrating detailed physiological responses to the broader questions of ecological and evolutionary responses to global climate change. Bridging the gap between large-scale records of weather and climate (as measured by remote sensing platforms, buoys and ground-based weather stations) and the physical world as experienced by organisms (niche-level measurements) requires a mechanistic understanding of how ‘environmental signals’ (parameters such as air, surface and water temperature, food availability, water flow) are translated into signals at the scale of the organism or cell (e.g. body temperature, …


Spatiotemporal Dynamics Of Immature Culicines (Subfamily Culicinae) And Their Larval Habitats In Mwea Rice Scheme, Kenya, Ephantus J. Muturi, Joseph M. Mwangangi, Benjamin G. Jacob, Josephat I. Shililu, Charles M. Mbogo, John I. Githure, Robert J. Novak Mar 2009

Spatiotemporal Dynamics Of Immature Culicines (Subfamily Culicinae) And Their Larval Habitats In Mwea Rice Scheme, Kenya, Ephantus J. Muturi, Joseph M. Mwangangi, Benjamin G. Jacob, Josephat I. Shililu, Charles M. Mbogo, John I. Githure, Robert J. Novak

All Peer-Reviewed Publications

An ecological study was conducted at three study sites in Mwea Rice Scheme, Kenya to identify the diverse aquatic habitats in which culicine mosquitoes thrived and to explore the best strategies for mosquito control in the area. During the 11-month study period, ten habitat categories and 11 culicine species mainly dominated by Culex quinquefasciatus (72.0%) and Culex annulioris (17.9%) were identified from pupae and late instars larval samples. Two of the 11 culicine species, Ficalbia (Mimomyia) plumosa and Uranotaenia spp., have not been reported previously in the study area. Rurumi had more habitat types than either of the other study …


Effect Of Noxious Stimulation Upon Antipredator Responses And Dominance Status In Rainbow Trout, Paul J. Ashley, Sian Ringrose, Katie L. Edwards, Emma Wallington, Catherine R. Mccrohan, Lynne U. Sneddon Feb 2009

Effect Of Noxious Stimulation Upon Antipredator Responses And Dominance Status In Rainbow Trout, Paul J. Ashley, Sian Ringrose, Katie L. Edwards, Emma Wallington, Catherine R. Mccrohan, Lynne U. Sneddon

Aquaculture Collection

A potentially painful experience may modify normal behavioural responses. To gauge the importance of pain relative to predation or social status, we presented competing stimuli, a predator cue or an unfamiliar social group, to two groups of noxiously treated rainbow trout, Oncorhynchus mykiss. In the predator cue experiment, fish were classified as bold or shy. Noxiously stimulated fish did not show antipredator responses, suggesting that pain is the imperative. In the social status experiment, noxiously stimulated fish held individually and undisturbed showed an increase in respiration rate and plasma cortisol. As a comparison, we used the dominant or subordinate fish …


Fisheries Research Report No. 183 - Development Of A Long-Term Program To Monitor Coastal Communities Within The Swan Region, Lynda M. Bellchambers Feb 2009

Fisheries Research Report No. 183 - Development Of A Long-Term Program To Monitor Coastal Communities Within The Swan Region, Lynda M. Bellchambers

Fisheries Research Reports

Marine benthic communities along the metropolitan coast of Western Australia are varied and unique. The southward flowing Leeuwin Current brings warm water and tropical recruits whilst the cooler counter current, the Capes Current, brings the temperate recruits. The result is a mosaic of tropical species intermingled with the dominant temperate species. These areas sustain varied fish and invertebrate communities making this coast a highly desirable location for recreational and commercial use. Management strategies are in place that attempt to maintain the sustainability of this area including various fishery restrictions and the implementation of areas zoned as sanctuary zones (no-take). However, …


Parallel Shifts In Ecology And Natural Selection In An Island Lizard, Ryan Calsbeek, Wolfgang Buermann, Thomas B. Smith Jan 2009

Parallel Shifts In Ecology And Natural Selection In An Island Lizard, Ryan Calsbeek, Wolfgang Buermann, Thomas B. Smith

Dartmouth Scholarship

Natural selection is a potent evolutionary force that shapes phenotypic variation to match ecological conditions. However, we know little about the year-to-year consistency of selection, or how inter-annual variation in ecology shapes adaptive landscapes and ultimately adaptive radiations. Here we combine remote sensing data, field experiments, and a four-year study of natural selection to show that changes in vegetation structure associated with a severe drought altered both habitat use and natural selection in the brown anole, Anolis sagrei.

Results: In natural populations, lizards increased their use of vegetation in wet years and this was correlated with selection on limb length …


Blackbrush Shrublands: Fire Conditions And Solutions In The Mojave Desert, Lisa-Natalie Anjozian Jan 2009

Blackbrush Shrublands: Fire Conditions And Solutions In The Mojave Desert, Lisa-Natalie Anjozian

Joint Fire Science Program Briefs (2007-2012)

While mature stands of blackbrush present an almost continuous cover that appears to suppress other species, this ecosystem supports a greater array of different plant species than was previously thought. Fire can completely remove blackbrush cover, but it also results in reduced numbers of other native species, and increased dominance of non-native species such as annual grasses that can promote recurrent fi re and alter the fi re regime. Where blackbrush shrublands historically experienced intense fi res with a long fi re return interval, the non-native fi ne fuels that are now prevalent in many stands promote a greater rate …


Little Umpqua Gentian And The Big Biscuit Fire, Lisa-Natalie Anjozian Jan 2009

Little Umpqua Gentian And The Big Biscuit Fire, Lisa-Natalie Anjozian

Joint Fire Science Program Briefs (2007-2012)

Umpqua gentian is an imperiled plant of the gaps and forested places, growing from the central western Cascade Mountains of Oregon, south to the Klamath Mountains in northwestern California. Since 1993, the Bureau of Land Management (BLM) and the Forest Service have worked together on a conservation strategy for this rare species, with the goal of maintaining viable, stable populations of genetic diversity. On the Medford District of the BLM, three sites had been monitored each year since 1995. When the 2002 Biscuit Fire burned the area, scientists had no information on how burning would affect this species. The Biscuit …


Macrofauna Associate With Ungrounded Prop Roots Of Rhizophora Mangle In Veracruz And Quintana Roo, Mexico, Kathryn D. Tunnell, Kim Withers Jan 2009

Macrofauna Associate With Ungrounded Prop Roots Of Rhizophora Mangle In Veracruz And Quintana Roo, Mexico, Kathryn D. Tunnell, Kim Withers

Gulf and Caribbean Research

The prop roots of the red mangrove (Rhizophora mangle) provide a solid substrate for diverse assemblages of marine organisms in areas typically characterized by soft bottoms (Bingham 1992, Farnsworth and Ellison 1996). Macrobenthic communities of mangroves have received little attention compared with other components of the ecosystem, largely due to sampling difficulties (Lee 2008). Mangrove root epifauna are likely used by predatory fish, especially juveniles. Thus, these organisms have the potential of being important links between mangroves and adjacent ecosystems. The fauna associated with red mangrove prop roots along Mexican Gulf of Mexico (GOM) and Caribbean shorelines has …


The Role Of Landscape Connectivity In Assembling Exotic Plant Communities: A Network Analysis, Emily S. Minor, Samantha M. Tessel, Katharina A.M. Engelhardt, Todd R. Lookingbill Jan 2009

The Role Of Landscape Connectivity In Assembling Exotic Plant Communities: A Network Analysis, Emily S. Minor, Samantha M. Tessel, Katharina A.M. Engelhardt, Todd R. Lookingbill

Geography and the Environment Faculty Publications

Landscape fragmentation and exotic species invasions are two modern-day forces that have strong and largely irreversible effects on native diversity worldwide. The spatial arrangement of habitat fragments is critical in affecting movement of individuals through a landscape, but little is known about how invasive species respond to landscape configuration relative to native species. This information is crucial for managing the global threat of invasive species spread. Using network analysis and partial Mantel tests to control for covarying environmental conditions, we show that forest plant communities in a fragmented landscape have spatial structure that is best captured by a network representation …


Lifelines Winter 2009, Southern Adventist University Jan 2009

Lifelines Winter 2009, Southern Adventist University

Lifelines - Biology Department Newsletter

The Winter 2009 issue of Lifelines features articles on RAM Clinics, Dr. Earl Aagaard's retirement, the addition of Richard Seidel to the faculty, and a pictorial directory of the 2009 biology and allied health graduates.


Advances In Serpentine Geoecology: A Retrospective, N Rajakaruna, R S. Boyd Jan 2009

Advances In Serpentine Geoecology: A Retrospective, N Rajakaruna, R S. Boyd

Faculty Publications, Biological Sciences

No abstract provided.


Serpentine Geoecology Of Eastern North America: A Review, Nishanta Rajakaruna, Tanner B. Harris, Earl B. Alexander Jan 2009

Serpentine Geoecology Of Eastern North America: A Review, Nishanta Rajakaruna, Tanner B. Harris, Earl B. Alexander

Biological Sciences

Serpentine outcrops are model habitats for geoecological studies. While much attention has been paid to serpentine outcrops worldwide, the literature on eastern North American serpentine and associated biota is scant. This review examines the available literature, published and unpublished, on geoecological studies conducted on serpentine in eastern North America, from Newfoundland through Québec and New England south to Alabama. Most serpentine outcrops in the region have been mapped, but there have been few intensive mineralogical and pedological investigations. The limited soil analyses available suggest elevated levels of heavy metals such as Ni, near-neutral pH values, and Ca∶Mg ratios < 1, characteristic of serpentine soils worldwide. Botanical studies to date have largely focused on floristic surveys and the influence of fire exclusion and grazing on indigenous vegetation. To date, 751 taxa of vascular plants belonging to 92 families have been reported from serpentine outcrops in the region. Two taxa, Agalinis acuta …


Birds Of The Great Plains: References, Paul A. Johnsgard Jan 2009

Birds Of The Great Plains: References, Paul A. Johnsgard

Birds of the Great Plains (Revised Edition, 2009) by Paul Johnsgard

A 21-page bibliography, including REGIONAL AND STATE REFERENCES and REFERENCES ON INDIVIDUAL SPECIES. Approximately 400 entries, through 1979.

An updated list of references will be found at the end of the new essay "Three Decades of Change in Great Plains Birds."


The Influence Of Spatial Scale On Landcover And Avian Community Relationships Within The Upper Green River Watershed, Ky, Cabrina L. Hamilton Jan 2009

The Influence Of Spatial Scale On Landcover And Avian Community Relationships Within The Upper Green River Watershed, Ky, Cabrina L. Hamilton

Mahurin Honors College Capstone Experience/Thesis Projects

Landscape ecology studies are needed to aid land managers and conservationists in developing management plans that will effectively improve avian population trends. This study uses riparian avian point count survey data and landcover data to examine the possible relationships between riparian avian communities and landcover within the Upper Green River watershed. How avian-landcover relationships change with increasing spatial scale is also examined. Results showed unexpected avian-landcover relationships for specific species. A landcover gradient from open and successional habitat to closed, forest habitat was most prevalent in the study area and explained most of the variation within the avian datasets. Riparian …


Rapid Recovery Of A Coral Reef At Darwin Island, Galapagos Islands, Peter W. Glynn, Bernhard Riegl, Adrienne M. S. Correa, Iliana B. Baums Jan 2009

Rapid Recovery Of A Coral Reef At Darwin Island, Galapagos Islands, Peter W. Glynn, Bernhard Riegl, Adrienne M. S. Correa, Iliana B. Baums

Marine & Environmental Sciences Faculty Articles

Surveys at Darwin Island in 2006 and 2007 have demonstrated that this northernmost Galapagos Islands coral reef has recovered significantly since the 1982–3 El Niño event. When first surveyed in 1975, this structural reef exhibited actively accreting frameworks of pocilloporid and poritid corals. The coral suffered severe mortality in 1983, resulting in the near total loss of pocilloporids and extensive partial mortality of poritid corals. Large sections of the reef had not recovered by 1992 and dead frameworks were subject to bio-erosion, although small numbers of sexual recruits of pocilloporid corals and numerous recruits plus regenerating patches of Porites lobata …


Estimating Predation On Declining River Herring: Tag-Recapture Study Of Striped Bass In The Connecticut River, Eric T. Schultz, Justin P. Davis, Jason Vokoun Jan 2009

Estimating Predation On Declining River Herring: Tag-Recapture Study Of Striped Bass In The Connecticut River, Eric T. Schultz, Justin P. Davis, Jason Vokoun

EEB Articles

Populations of anadromous alewife Alosa pseudoharengus and blueback herring Alosa aestivalis, collectively referred to as river herring, have declined in the Connecticut River. A hypothesis for why river herring have declined is that predation pressures have increased associated with recent increases in abundance of striped bass Morone saxatilis. Information on striped bass abundance, size structure, and consumption rates are required to test this hypothesis. This study was designed to provide estimates of striped bass population size in the Connecticut River during the spring migration season, via an intensive mark-recapture exercise and either an open or robust mark-recapture model. …


Birds Of The Rocky Mountains—References On Individual Species, Paul A. Johnsgard Jan 2009

Birds Of The Rocky Mountains—References On Individual Species, Paul A. Johnsgard

Birds of the Rocky Mountains by Paul A. Johnsgard

Approximately 650 reference (through 1986). See "Supplement" for additional references to 2009.


Habitat Variation Among Aquatic Gastropod Assemblages Of Indiana, U.S.A., Mark Pyron, Jayson Beugly, Matthew Spielman, Jennifer Pritchett, Stephen J. Jacquemin Jan 2009

Habitat Variation Among Aquatic Gastropod Assemblages Of Indiana, U.S.A., Mark Pyron, Jayson Beugly, Matthew Spielman, Jennifer Pritchett, Stephen J. Jacquemin

Biological Sciences Faculty Publications

We collected aquatic gastropods at 137 sites in lakes and streams of Indiana and tested for patterns of assemblages with environmental variables. The survey resulted in 32 species with a mean of 2.8 species at each site, and a mean abundance at each site of 144 individuals. Nonmetric multidimensional scaling (NMS) multivariate analyses resulted in watershed drainage area, water conductivity, substrate category frequency, and dissolved oxygen as significant correlates of gastropod assemblage structure. Gastropod assemblages of lakes were not significantly different than assemblages of streams in the ordination. Prosobranch taxa occurred in higher abundances than pulmonate taxa at sites with …