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Leptodactylus Savagei, W. R. Heyer, Miriam M. Heyer, Rafael O. de Sá 2010 University of Richmond

Leptodactylus Savagei, W. R. Heyer, Miriam M. Heyer, Rafael O. De Sá

Biology Faculty Publications

Adult Leptodactylus savagei are large, the head is as wide as long or usually wider than long, and the hind limbs are moderate in length (Table 1; Heyer and Thompson (2000) provided definitions of adult size and leg length categories for Leptodactylus). Male vocal sacs are not visible externally. Sexually active males have hypertrophied forearms, usually 1 large black spine on each thumb, rarely with 1 large spine and a prepollical bump, and a pair of black chest spines. A pair of entire dorsolateral folds extend anteriorly from at least one_half to full distance from eye to groin, the …


Environmental Effects On Behavior And Physiology In Crayfish, Sonya M. Bierbower 2010 University of Kentucky

Environmental Effects On Behavior And Physiology In Crayfish, Sonya M. Bierbower

University of Kentucky Doctoral Dissertations

Despite dramatic morphological differences between animals from different taxa, several important features in organization and sensory system processing are similar across animals. Because of this similarity, a number of different organisms including mammals, insects, and decapod crustaceans serve as valuable model systems for understanding general principles of environmental effects. This research examines intrinsic and extrinsic factors by behaviorally and physiologically means to identify the impact of environmental conditions on two distinct crayfish species- Procambarus clarkii (surface) and Orconectes australis packardi (cave).

The research identified behavioral and physiological responses in these two morphological and genetically distinct species. The studies also examined …


A Sketch-Based Language For Representing Uncertainty In The Locations Of Origin Of Herbarium Specimens, Barry J. Kronenfeld, Andrew Weeks 2010 Eastern Illinois University

A Sketch-Based Language For Representing Uncertainty In The Locations Of Origin Of Herbarium Specimens, Barry J. Kronenfeld, Andrew Weeks

Faculty Research and Creative Activity

Uncertainty fields have been suggested as an appropriate model for retrospective georeferencing of herbarium specimens. Previous work has focused only on automated data capture methods, but techniques for manual data specification may be able to harness human spatial cognition skills to quickly interpret complex spatial propositions. This paper develops a formal modeling language by which location uncertainty fields can be derived from manually sketched features. The language consists of low-level specification of critical probability isolines from which a surface can be uniquely derived, and high-level specification of features and predicates from which low-level isolines can be derived. In a case …


Muellerius Capillaris Dominates The Lungworm Community Of Bighorn Sheep At The National Bison Range, Montana, Vanessa O. Ezenwa, Alicia M. Hines, Elizabeth A. Archie, Eric P. Hoberg, Ingrid M. Asmundsson, John T. Hogg 2010 University of Montana - Missoula

Muellerius Capillaris Dominates The Lungworm Community Of Bighorn Sheep At The National Bison Range, Montana, Vanessa O. Ezenwa, Alicia M. Hines, Elizabeth A. Archie, Eric P. Hoberg, Ingrid M. Asmundsson, John T. Hogg

Harold W. Manter Laboratory of Parasitology: Faculty and Staff Publications

Lungworm infections are common among bighorn sheep (Ovis canadensis) in North America, and the predominant species reported are Protostrongylus stilesi and P. rushi. The only records of another lungworm species, Muellerius capillaris, infecting bighorns come from South Dakota, USA. At the National Bison Range (NBR), Montana, USA we found that across six sampling periods, 100% of wild bighorn sheep surveyed were passing first-stage dorsal-spined larvae (DSL) which appeared to be consistent with M. capillaris. By contrast, only 39%or fewer sheep were passing Protostrongylus larvae. Using molecular techniques, we positively identified the DSL from the NBR …


The Ratio Of Gametophytes To Tetrasporophytes Of Intertidal Chondrus Crispus (Gigartinaceae) Across A Salinity Gradient, Michele Guidone, Sean Grace 2010 Sacred Heart University

The Ratio Of Gametophytes To Tetrasporophytes Of Intertidal Chondrus Crispus (Gigartinaceae) Across A Salinity Gradient, Michele Guidone, Sean Grace

Biology Faculty Publications

Population studies of the Gigartinaceae (Rhodophyta) have often observed that the ratio of gametophytes to tetrasporophytes varies with the location of the population or the time of sampling. For some species, patterns have emerged that correlate this ratio to one or a few particular environmental variables, such as elevation, wave exposure, or season. Identifying these distributional patterns is an important step towards understanding what (if any) ecological differences exist between the two free-living life history stages.

The purpose of this study was to measure the ratio of gametophytes to tetrasporophytes of intertidal populations of Chondrus crispus across a decreasing salinity …


Snail Grazing Facilitates Growth Of A Bloom-Forming Alga, Michele Guidone, Carol S. Thornber, Emily Field 2010 Sacred Heart University

Snail Grazing Facilitates Growth Of A Bloom-Forming Alga, Michele Guidone, Carol S. Thornber, Emily Field

Biology Faculty Publications

Herbivory often has a negative effect on plants. However, there is a growing number of examples, primarily in terrestrial ecosystems, where herbivory causes an increase in plant size, growth rate, and/or reproductive output. In marine ecosystems, the positive effects of herbivores on macroalgae are not as well studied, although limited evidence exists for herbivore-induced increases in macroalgal growth rates via 2 mechanisms: nutrient addition via grazer defecation, and epiphyte removal. In this study, we examined the effects of grazing by the mud snail Ilyanassa obsoleta on Ulva lactuca, the dominant bloom-forming macroalga in many New England estuaries. We found …


A Sketch-Based Language For Representing Uncertainty In The Locations Of Origin Of Herbarium Specimens, Barry Kronenfeld, Andrew Weeks 2010 Eastern Illinois University

A Sketch-Based Language For Representing Uncertainty In The Locations Of Origin Of Herbarium Specimens, Barry Kronenfeld, Andrew Weeks

Faculty Research and Creative Activity

Uncertainty fields have been suggested as an appropriate model for retrospective georeferencing of herbarium specimens. Previous work has focused only on automated data capture methods, but techniques for manual data specification may be able to harness human spatial cognition skills to quickly interpret complex spatial propositions. This paper develops a formal modeling language by which location uncertainty fields can be derived from manually sketched features. The language consists of low-level specification of critical probability isolines from which a surface can be uniquely derived, and high-level specification of features and predicates from which low-level isolines can be derived. In a case …


Proportion Of Calves And Adult Muskoxen, Ovibos Moschatus Killed By Gray Wolves, Canis Lupus, In July On Ellesmere Island, L. David Mech 2010 USGS Northern Prairie Wildlife Research Center

Proportion Of Calves And Adult Muskoxen, Ovibos Moschatus Killed By Gray Wolves, Canis Lupus, In July On Ellesmere Island, L. David Mech

USGS Northern Prairie Wildlife Research Center

Generally Gray Wolves (Canis lupus L., 1758) tend to focus predation on young-of-the-year ungulates during summer, and I hypothesized that wolves preying on Muskoxen (Ovibos moschatus Zimmerman, 1780) in summer would follow that trend. Over 23 July periods observing wolves on Ellesmere Island, Nunavut, Canada, I found that packs of 2-12 adult wolves killed seven calves, one yearling, and five adult muskoxen at distances of 2.9 to 32 km from their current dens and pups. Given a possible bias against finding calves because of their fewer remains, these results do not necessarily refute the hypothesis, but they do …


Trophic Implications Of Light Reductions For Amphibolis Griffithii Seagrass Fauna, Adam Gartner 2010 Edith Cowan University

Trophic Implications Of Light Reductions For Amphibolis Griffithii Seagrass Fauna, Adam Gartner

Theses: Doctorates and Masters

The ongoing threat of seagrass loss from reduced light availability, coupled with our lack of knowledge of associated trophic responses has motivated this characterization of the flow-on effects of light reductions to Amphibolis griffithii seagrass fauna. Recently, field manipulations of varying light reductions, induced disturbances in a A. griffithii seagrass meadow that have been shown to effect potential food resources and the structural complexity of seagrass habitats for macroinvertebrates. This offered the opportunity to assess the flow-on effects to seagrass for fauna, a topic that has seldom been examined. This study investigated the effects of different light reduction intensity (high: …


Ignoring Nature: Why We Do It, The Dire Consequences, And The Need For A Paradigm Shift To Save Animals, Habitats, And Ourselves, Marc Bekoff, Sarah Bexell 2010 University of Colorado Boulder

Ignoring Nature: Why We Do It, The Dire Consequences, And The Need For A Paradigm Shift To Save Animals, Habitats, And Ourselves, Marc Bekoff, Sarah Bexell

Ecology Collection

The article discusses the importance of biodiversity and on how people protect animals and habitats. It describes the conservation psychology and conservation social work. It suggests that there will be fewer people who will actually be able to make a positive difference in the relationships with animals and ecosystems.


Promiscuous Mating In Feral Pigs (Sus Scrofa) From Texas, Usa, Johanna Delgado-Acevedo, Angeline Zamorano, Randy W. DeYoung, Tyler A. Campbell, David G. Hewitt, David B. Long 2010 Texas A&M University-Kingsville

Promiscuous Mating In Feral Pigs (Sus Scrofa) From Texas, Usa, Johanna Delgado-Acevedo, Angeline Zamorano, Randy W. Deyoung, Tyler A. Campbell, David G. Hewitt, David B. Long

USDA Wildlife Services: Staff Publications

Context. Feral pigs represent a significant threat to agriculture and ecosystems and are disease reservoirs for pathogens affecting humans, livestock and other wildlife. Information on the behavioural ecology of feral pigs might increase the efficiency and effectiveness of management strategies.

Aims. We assessed the frequency of promiscuous mating in relation to oestrous synchrony in feral pigs from southern Texas, USA, an agroecosystem with a widespread and well established population of feral pigs. An association between multiple paternity of single litters and synchrony of oestrous may indicate alternative mating strategies, such as mateguarding.

Methods. We collected gravid sows at …


Gps-‐‐Basedmeasurements Of Backcountry Visitors In Parks And Protected Areas: Examples Of Methods And Applications From Three Case Studies, A. D'Antonio, Christopher Monz, S. Lawson, P. Newman 2010 Utah State University

Gps-‐‐Basedmeasurements Of Backcountry Visitors In Parks And Protected Areas: Examples Of Methods And Applications From Three Case Studies, A. D'Antonio, Christopher Monz, S. Lawson, P. Newman

Christopher Monz

No abstract provided.


Sandhill Crane Staging And Whooping Crane Migratory Stopover Dynamics In Response To River Management Activities On The Central Platte River, Nebraska, Usa, FELIPE CHAVEZ-RAMIREZ 2010 Platte River Whooping Crane Maintenance Trust

Sandhill Crane Staging And Whooping Crane Migratory Stopover Dynamics In Response To River Management Activities On The Central Platte River, Nebraska, Usa, Felipe Chavez-Ramirez

Proceedings of the North American Crane Workshop

The Central Platte River Valley (CPRV) is a critical stopover for migrating whooping cranes (Grus americana) and the most important staging area for sandhill cranes (G. canadensis) in North America. Due to reduced water flows caused by human activities, the Platte River no longer follows its traditional hydrograph which consisted of high spring flows that produced scouring action that eliminated vegetation. To provide adequate crane roosting habitat during stopover and staging periods, annual and woody vegetation has been mechanically cleared on eastern portions of the CPRV since 1980. Staging sandhill crane riverine roosting area has decreased …


Evaluating Propagation Method Performance Over Time With Bayesian Updating: An Application To Incubator Testing, SARAH J. CONVERSE, JANE N. CHANDLER, GLENN H. OLSEN, CHARLES C. SHAFER 2010 USGS Patuxent Wildlife Research Center

Evaluating Propagation Method Performance Over Time With Bayesian Updating: An Application To Incubator Testing, Sarah J. Converse, Jane N. Chandler, Glenn H. Olsen, Charles C. Shafer

Proceedings of the North American Crane Workshop

In captive-rearing programs, small sample sizes can limit the quality of information on performance of propagation methods. Bayesian updating can be used to increase information on method performance over time. We demonstrate an application to incubator testing at USGS Patuxent Wildlife Research Center. A new type of incubator was purchased for use in the whooping crane (Grus americana) propagation program, which produces birds for release. We tested the new incubator for reliability, using sandhill crane (Grus canadensis) eggs as surrogates. We determined that the new incubator should result in hatching rates no more than 5% lower …


Preliminary Wintering Counts And New Locations Of Sandhill Cranes In Mexico, INGRID BARCELÓ, EDGAR G. LÓPEZ, FELIPE CHÁVEZ-RAMÍREZ 2010 University of Nebraska-Lincoln

Preliminary Wintering Counts And New Locations Of Sandhill Cranes In Mexico, Ingrid Barceló, Edgar G. López, Felipe Chávez-Ramírez

Proceedings of the North American Crane Workshop

Sandhill cranes (Grus canadensis) undertake a migration twice a year, when more than 400,000 cranes cross the United States from the Arctic of North America and Eastern Siberia to the southwest U.S. and north central Mexico. Although the sandhill crane has been studied intensely, few studies have been done on their Mexican wintering grounds. Little is known about what proportion of the sandhill crane population migrates to Mexico, and there is even less information regarding its dispersion. During winter 2007-2008 we surveyed 30 wetlands in the Chihuahuan Desert ecoregion in northern Mexico, recording presence/absence and number of sandhill …


Behavior And Habitat Use Of Greater Sandhill Cranes Wintering In East Tennessee, DAVID A. ABORN 2010 University of Tennessee at Chattanooga

Behavior And Habitat Use Of Greater Sandhill Cranes Wintering In East Tennessee, David A. Aborn

Proceedings of the North American Crane Workshop

An increase of eastern greater sandhill cranes (Grus canadensis tabida) stopping over and wintering at the Hiwassee Wildlife Refuge in east Tennessee has led to overcrowding at the refuge, resulting in crane use of private property. Proper management is needed to prevent the cranes from becoming a nuisance, increase the suitability of the refuge for waterfowl, and reduce the likelihood of a disease outbreak. Observations of cranes revealed that cranes spent 83% of their time foraging, alert, or preening. Sandhill cranes foraged primarily in agricultural and grassy fields, whereas mudflats and shallow water were used for preening and …


Leg Problems And Power Line Interactions In The Florida Resident Flock Of Whooping Cranes, JAIMIE L. MILLER, MARILYN G. SPALDING, MARTIN J. FOLK 2010 University of Florida

Leg Problems And Power Line Interactions In The Florida Resident Flock Of Whooping Cranes, Jaimie L. Miller, Marilyn G. Spalding, Martin J. Folk

Proceedings of the North American Crane Workshop

We retrospectively reviewed a database with over 1,800 health entries from 296 captive-reared whooping cranes (Grus americana) released in central Florida and 10 wild-fledged chicks from 1992 to 2007. Fifty percent of the study population (n = 306) had 1 or more leg problems that were placed into 4 broad categories: power line interactions (n = 39), other trauma (n = 94), deformities (n = 43), and miscellaneous conditions (n = 106). More males (n = 26, 67%) had power line interactions than females (n = 13, 33%). The majority of these 39 birds died (57%), while the …


Study Of Environmental Variables And Connectivity Of Northern Mexico For Cranes: Conservation Implications, EDGAR GUSTAVO LÓPEZ-SAUT, RICARDO RODRIGUEZ ESTRELLA, FELIPE CHAVEZ-RAMIREZ 2010 Centro de Inverstigaciones Biologicas del Noroeste

Study Of Environmental Variables And Connectivity Of Northern Mexico For Cranes: Conservation Implications, Edgar Gustavo López-Saut, Ricardo Rodriguez Estrella, Felipe Chavez-Ramirez

Proceedings of the North American Crane Workshop

Wetlands are one of the most important ecosystems for biodiversity and as a resource for humans. Humans depend on wetlands for water and food, but with expansion of urban cores, water overexploitation, and the increase of croplands, wetlands are at risk. The Chihuahuan desert is an ecoregion important for the economy and development of Mexico. Although there are many temporal wetlands that support many migratory birds, water in some desert landscapes is being overexploited due to development. This leads to the desiccation of wetlands important for migratory birds such as cranes. The cranes as a group are associated with grasslands …


Causes Of Embryonic Death In Captive Whooping Cranes, JULIA N. LETOUTCHAIA, KELLY MAGUIRE, BARRY K. HARTUP 2010 Michigan State University

Causes Of Embryonic Death In Captive Whooping Cranes, Julia N. Letoutchaia, Kelly Maguire, Barry K. Hartup

Proceedings of the North American Crane Workshop

In 2001, the International Whooping Crane Recovery Team and the Whooping Crane Health Advisory Team reemphasized the need for analysis of embryonic deaths within captive breeding flocks to identify preventable deaths and promote increased production of chicks for release programs. We conducted a retrospective study of egg necropsy reports to identify causes of death among developing whooping crane (Grus americana) embryos from captivity. Records from 44 egg necropsies conducted at the International Crane Foundation (ICF) between 2001 and 2008 were reviewed. The eggs were of captive origin (ICF, n = 40; Patuxent Wildlife Research Center, n = 3; …


Migration Patterns And Movements Of Sandhill Cranes Wintering In Central And Southwestern Louisiana, SAMMY L. KING, AARON R. PIERCE, KENT R. HERSEY, NICHOLAS WINSTEAD 2010 Louisiana Cooperative Fish and Wildlife Research Unit, U.S. Geological Survey

Migration Patterns And Movements Of Sandhill Cranes Wintering In Central And Southwestern Louisiana, Sammy L. King, Aaron R. Pierce, Kent R. Hersey, Nicholas Winstead

Proceedings of the North American Crane Workshop

In this study we trapped wintering sandhill cranes (Grus canadensis) in Louisiana and fitted them with satellite transmitters to determine their migration routes. Four of the 6 sandhill cranes with validated locations and a terminus point used the Central Flyway for spring migration; 2 of these 4 (the only 2 for which we have data) also used the Central Flyway for fall migration. Two of the 6 birds used the Mississippi Flyway for spring migration. The results of this study suggest that reintroduced whooping cranes (G. americana) that intermix and migrate with sandhill cranes that winter …


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