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The Institute For Raptor Studies Expeditions In Mongolia, 1994-2000, David H. Ellis Jan 2010

The Institute For Raptor Studies Expeditions In Mongolia, 1994-2000, David H. Ellis

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

In 1994, 1995, 1997, 1998, and 2000, I led small teams of biologists across Mongolia in search of Saker falcon (Falco cherrug Gray) and golden eagle (Aquila chrysaetos) eyries. We also counted raptors along our march route during the first three years. These expeditions documented: (1) occupancy and productivity rates, and described eyrie sites, for Saker falcons (150 territories, 182 eyries) and golden eagles (27 known breeding territories), (2) mortality of Sakers and ipland buzzards (Buteo hemilasius) due to entanglement with trash in nests and loss of golden eagle eggs due to concealment by trash in nests, …

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Current State Of Ixodidae Research In Mongolia, Daniel Kiefer, K. Pfister, D. Tserennorov, G. Bolormaa, D. Otgonbaatar, Ravčigijn Samjaa, E. G. Burmeister, Mathias S. Kiefer Jan 2010

Current State Of Ixodidae Research In Mongolia, Daniel Kiefer, K. Pfister, D. Tserennorov, G. Bolormaa, D. Otgonbaatar, Ravčigijn Samjaa, E. G. Burmeister, Mathias S. Kiefer

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

Our research presents the Ixodidae-fauna in Mongolia. The current taxonomic state in Mongolia shows 19 Ixodidae taxa extracted in 308 locations from 115 bird and mammal species. In 1980, the species Ixodes persulcatus SCHULZE, 1930 and Ixodes berlesei Birula, 1895 were detected in Inget Tolgoi and Ixodes laguri OLENEV, 1929 on Meriones unguiculatus 10 km southeast of Ulaanbaatar for the first time. In 2000 the species Haemaphysalis concinna Koch, 1844 was detected in the Selenge-river area and Argas (Argas) vulgaris FILIPPOVA, 1961 was detected in the Gobi area. From the collection of M. and A. STUBBE 1 N …

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Evidence Of Pachyostosis In The Cryptocleidoid Plesiosaur Tatenectes Laramiensis From The Sundance Formation Of Wyoming, Hallie P. Street, F. Robin O’Keefe Jan 2010

Evidence Of Pachyostosis In The Cryptocleidoid Plesiosaur Tatenectes Laramiensis From The Sundance Formation Of Wyoming, Hallie P. Street, F. Robin O’Keefe

Biological Sciences Faculty Research

In this paper we present evidence for pachyostosis in the cryptocleidoid plesiosaur Tatenectes laramiensis Knight, 1900 (O'Keefe and Wahl, 2003a). Pachyostosis is not common in plesiosaurs and is particularly rare in non-pliosaurian plesiosaurs, although enlarged gastralia were first recognized in Tatenectes by Wahl (1999). This study aims to investigate the nature of the disproportionately large gastralia of Tatenectes m greater depth, based on new material. A recently discovered partial skeleton consisting of a dorsal vertebral series, ribs, gastralia, and a complete pelvic girdle was collected from the Jurassic-aged Sundance Formation of the Bighorn Basin in Wyoming during the summer of …

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Cognitive Representation In Transitive Inference: A Comparison Of Four Corvid Species, Alan B. Bond, Cynthia A. Wei, Alan C. Kamil Jan 2010

Cognitive Representation In Transitive Inference: A Comparison Of Four Corvid Species, Alan B. Bond, Cynthia A. Wei, Alan C. Kamil

Alan Bond Publications

During operant transitive inference experiments, subjects are trained on adjacent stimulus pairs in an implicit linear hierarchy in which responses to higher ranked stimuli are rewarded. Two contrasting forms of cognitive representation are often used to explain resulting choice behavior. Associative representation is based on memory for the reward history of each stimulus. Relational representation depends on memory for the context in which stimuli have been presented. Natural history characteristics that require accurate configural memory, such as social complexity or reliance on cached food, should tend to promote greater use of relational representation. To test this hypothesis, four corvid species …

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Pollen Interception By Linyphiid Spiders In A Corn Agroecosystem: Implications For Dietary Diversification And Risk-Assessment, Julie A. Peterson, Susan Romero, James D. Harwood Jan 2010

Pollen Interception By Linyphiid Spiders In A Corn Agroecosystem: Implications For Dietary Diversification And Risk-Assessment, Julie A. Peterson, Susan Romero, James D. Harwood

West Central Research and Extension Center, North Platte

Dietary diversification, including consumption of plant tissues such as pollen, can enhance the fecundity of generalist predators, resulting in improved control of pest prey. Supplemental pollen feeding has been observed in many natural enemies, including sheet-web spiders (Araneae: Linyphiidae), which represent a major component of food webs in agroecosystems. Their horizontal, ground-based webs have the potential to intercept pollen grains during anthesis of crop plants, providing the opportunity for consumption of pollen to occur. In laboratory feeding trials, Frontinella communis and Tennesseellum formicum (Araneae: Linyphiidae) readily fed on pollen grains dusted on their webs, with 82 and 92% of spiders …

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Diversity Of Interactions: A Metric For Studies Of Biodiversity, Lee A. Dyer, Thomas R. Walla, Harold F. Greeney, John O. Stireman Iii, Rebecca F. Hazen Jan 2010

Diversity Of Interactions: A Metric For Studies Of Biodiversity, Lee A. Dyer, Thomas R. Walla, Harold F. Greeney, John O. Stireman Iii, Rebecca F. Hazen

Biological Sciences Faculty Publications

Multitrophic interactions play key roles in the origin and maintenance of species diversity, and the study of these interactions has contributed to important theoretical advances in ecology and evolutionary biology. Nevertheless, most biodiversity inventories focus on static species lists, and prominent theories of diversity still ignore trophic interactions. The lack of a simple interaction metric that is analogous to species richness is one reason why diversity of interactions is not examined as a response or predictor variable in diversity studies. Using plant-herbivore-enemy trophic chains as an example, we develop a simple metric of diversity in which richness, diversity indices (e.g., …

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Global Assessment Of Nitrogen Deposition Effects On Terrestrial Plant Diversity : A Synthesis, R. Bobbink, K. Hicks, J. Galloway, T. Spranger, R. Alkemade, M. Ashmore, M. Bustamante, S. Cinderby, E. Davidson, F. Dentener, B. Emmett, J. W. Erisman, M. Fenn, Frank S. Gilliam, A. Nordin, L. Pardo, W. Devries Jan 2010

Global Assessment Of Nitrogen Deposition Effects On Terrestrial Plant Diversity : A Synthesis, R. Bobbink, K. Hicks, J. Galloway, T. Spranger, R. Alkemade, M. Ashmore, M. Bustamante, S. Cinderby, E. Davidson, F. Dentener, B. Emmett, J. W. Erisman, M. Fenn, Frank S. Gilliam, A. Nordin, L. Pardo, W. Devries

Biological Sciences Faculty Research

Atmospheric nitrogen (N) deposition is a recognized threat to plant diversity in temperate and northern parts of Europe and North America. This paper assesses evidence from field experiments for N deposition effects and thresholds for terrestrial plant diversity protection across a latitudinal range of main categories of ecosystems, from arctic and boreal systems to tropical forests. Current thinking on the mechanisms of N deposition effects on plant diversity, the global distribution of G200 ecoregions, and current and future (2030) estimates of atmospheric N-deposition rates are then used to identify the risks to plant diversity in all major ecosystem types now …

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Darwinian Populations And Natural Selection, Grant Ramsey, Hope Hollocher, Agustín Fuentes, Charles H. Pence, Edwin Siu Jan 2010

Darwinian Populations And Natural Selection, Grant Ramsey, Hope Hollocher, Agustín Fuentes, Charles H. Pence, Edwin Siu

Faculty Publications

No abstract provided.

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What Are The Causes, Consequences And Correctives Of Fish Contamination In The Detroit River Aoc That Cause Health Consumption Advisories? (Final Report, Michigan Sea Grant Michu-T-10-001), Donna R. Kashian, Ken G. Drouillard, D. Haffner, Ann E. Krause, Z Liu, Larissa Sano Jan 2010

What Are The Causes, Consequences And Correctives Of Fish Contamination In The Detroit River Aoc That Cause Health Consumption Advisories? (Final Report, Michigan Sea Grant Michu-T-10-001), Donna R. Kashian, Ken G. Drouillard, D. Haffner, Ann E. Krause, Z Liu, Larissa Sano

Environmental Science and Geology Faculty Research Publications

Using an Integrated Assessment (IA) framework, we consolidated and utilized existing data from the Detroit River to develop models that both identify possible drivers of elevated fish contaminant body burdens, and to facilitate a more risk-based approach of tissue trigger-levels for consumption advisories. This integrated assessment approach was particularly useful for consumption advisories as it provided the ability to integrate and organize complex data in a manner that can help inform management decisions. In addition, the IA framework explicitly fosters collaboration and participation of multiple interested groups. We have capitalized on this component of IAs, by seeking the active participation …

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Winter 2010, Nsu Oceanographic Center Jan 2010

Winter 2010, Nsu Oceanographic Center

Currents

No abstract provided.

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Effects Of Early Developmental Stress On Adult Physiology And Behavior, Michael James Frederick Jan 2010

Effects Of Early Developmental Stress On Adult Physiology And Behavior, Michael James Frederick

Legacy Theses & Dissertations (2009 - 2024)

Events during early development can have long-term effects on physiology and behavior. While extreme developmental stress is known to be associated with a variety of behavioral problems, it is less well understood how milder stress may affect behavior, personality, and reproductive success. This research project assessed a variety of behavioral dimensions in a college age sample, while assessing early development using size at birth, fluctuating asymmetry, and retrospective surveys. Maternal stress during pregnancy was found to reduce adolescent growth spurts and adult handgrip strength in the offspring. In males, lower birth weights were associated with higher scores of impulsivity and …

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Ecological Invasion In Spatially Competitive Systems, Andrew James Allstadt Jan 2010

Ecological Invasion In Spatially Competitive Systems, Andrew James Allstadt

Legacy Theses & Dissertations (2009 - 2024)

Although the term invasion conjures images of invasive species, the dynamics of rarity is fundamental to many ecological processes. The community-level effects of invasion are determined by interactions between individuals in the system. Competition is most intense between neighboring individuals, which may generate spatial organization that can affect the outcome and time scale of an invasion. In this dissertation, I use analytic and simulation models of invasion to study preemptive competition between a rare invading type, and a resident that already occupies the system. In Chapter 1, I give motivation for these studies, and then introduce a spatially structured, individual-based …

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Thirty Years Of Mortality Assessment In Whooping Crane Reintroductions: Patterns And Implications, Barry K. Hartup, Marilyn G. Spalding, Nancy J. Thomas, Gretchen A. Cole, Young Jun Kim Jan 2010

Thirty Years Of Mortality Assessment In Whooping Crane Reintroductions: Patterns And Implications, Barry K. Hartup, Marilyn G. Spalding, Nancy J. Thomas, Gretchen A. Cole, Young Jun Kim

Proceedings of the North American Crane Workshop

We reviewed postmortem data to identify primary causes of mortality in reintroduced whooping cranes (Grus americana) and assess their potential for mitigation in future reintroduction efforts. In total, 240 cases from 3 populations were reviewed for causes of death, including the Rocky Mountain migratory population (n = 24, release dates 1975-1989), the Florida resident population (n = 186, 1993-2005), and the Wisconsin migratory population (n = 30, 2001-ongoing). Traumatic injury was the leading cause of mortality among the reintroduced whooping cranes, most commonly from predation (n = 120 or 50%, range 8-58% per project) or collision with fixed …

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Morbidity And Mortality Of Captive Whooping Cranes At The International Crane Foundation 1976–2008, Barry K. Hartup, Jennifer N. Niemuth, Bridget Fitzpatrick, Maureen Fox, Cristin Kelley Jan 2010

Morbidity And Mortality Of Captive Whooping Cranes At The International Crane Foundation 1976–2008, Barry K. Hartup, Jennifer N. Niemuth, Bridget Fitzpatrick, Maureen Fox, Cristin Kelley

Proceedings of the North American Crane Workshop

Tracking the incidence of morbidity and mortality in captive animal collections helps inform husbandry and preventive medicine programs aimed at improving population health and viability. Carpenter and Derrickson (1982) and Olsen et al. (1997) published summary reports of captive whooping crane (Grus americana) mortality that served to identify key problem areas for the primary breeding flock and potential reintroduction programs involving this endangered species. We expanded on this approach and conducted an initial evaluation of morbidity and mortality factors for whooping cranes at the International Crane Foundation (ICF). The purpose of our study was to identify overrepresented factors …

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Endoparasites Of Greater Sandhill Cranes In South-Central Wisconsin, Somer Hartman, Betsy Reichenberg, Jane Fanke, Anne E. Lacy, Barry K. Hartup Jan 2010

Endoparasites Of Greater Sandhill Cranes In South-Central Wisconsin, Somer Hartman, Betsy Reichenberg, Jane Fanke, Anne E. Lacy, Barry K. Hartup

Proceedings of the North American Crane Workshop

Windingstad and Trainer (1977) used both fecal sampling and postmortem examinations to document the occurrence of parasites in greater sandhill cranes (Grus canadensis tabida) from Wisconsin in the fall. We conducted repeated fecal sampling of a well-known population to expand on results of their study. Our objective was to determine whether seasonal differences exist in the prevalence of endoparasites of Wisconsin sandhill cranes. We collected 7 to 10 fecal samples approximately every other week from a consistent roost site on the Wisconsin River (43°34'52.99''N, 89°36'38.42''W) near Briggsville, Wisconsin, from 29 May through 25 September 2008. The sample size …

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Impacts Of Global And Regional Climate On Whooping Crane Demography: Trends And Extreme Events, Karine Gil, William Grant, R. Douglas Slack, Enrique Weir Jan 2010

Impacts Of Global And Regional Climate On Whooping Crane Demography: Trends And Extreme Events, Karine Gil, William Grant, R. Douglas Slack, Enrique Weir

Proceedings of the North American Crane Workshop

We analyzed long-term demographic and environmental data to understand the role of large scale climatic factors (the Pacific Decadal Oscillations [PDO]) and environmental factors in 3 regions of North America on natality and mortality of the remnant migratory whooping crane (Grus americana) population. This is an endangered species that spends winters at Aransas National Wildlife Refuge (ANWR) in Texas, breeds at Wood Buffalo National Park (WBNP) in Canada and “…uses Nebraska as a primary stopover”. Long term data (27 years) of demography and environmental factors (PDO index, temperature and precipitation at WBNP, Nebraska and ANWR, pond water depth …

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Longevity Records Of Rocky Mountain Greater Sandhill Cranes Banded During 1969–1987 In Idaho, Montana, Utah, And Wyoming, Roderick C. Drewien, Wendy M. Brown, Kent R. Clegg Jan 2010

Longevity Records Of Rocky Mountain Greater Sandhill Cranes Banded During 1969–1987 In Idaho, Montana, Utah, And Wyoming, Roderick C. Drewien, Wendy M. Brown, Kent R. Clegg

Proceedings of the North American Crane Workshop

Cranes species throughout the world are renowned for their longevity; however, most records are based on individuals in captivity. We compiled longevity records for wild Rocky Mountain greater sandhill cranes (Grus canadensis tabida) banded in Idaho, Montana, Utah, and Wyoming during 1969-1987. Our analysis was based on over 180 band recoveries and over 1,700 visual observations of known-age individually marked birds from 1969 to 2008. We present only those birds of age >20 years for this summary. Our results yielded 56 birds known to be >20 yrs of age when killed or last observed. Of 7 band recoveries, …

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Demography Of Whooping Cranes In The Eastern Migratory Population, Sarah J. Converse, Richard P. Urbanek Jan 2010

Demography Of Whooping Cranes In The Eastern Migratory Population, Sarah J. Converse, Richard P. Urbanek

Proceedings of the North American Crane Workshop

The ultimate success of the whooping crane (Grus americana) reintroduction to eastern North America rests on adequate demographic performance of the population. We are undertaking a population viability analysis (PVA) of the eastern migratory population in order to evaluate progress toward the fundamental population objective, to better understand the critical demographic thresholds that must be met to fulfill this objective, and, most importantly, to support management decision-making. The initial phase in the PVA development process involves estimation of demographic parameters to be used in later population modeling phases. Multi-state models provide an appropriate analytic framework for estimation, wherein …

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Current Status Of Lesser Sandhill Cranes In Yakutia, Inga Bysykatova, Sergey Sleptsov, Nikolay Vasiliev Jan 2010

Current Status Of Lesser Sandhill Cranes In Yakutia, Inga Bysykatova, Sergey Sleptsov, Nikolay Vasiliev

Proceedings of the North American Crane Workshop

In Yakutia, the sandhill crane (Grus canadensis canadensis) was considered a common bird in 1957 on the Primorie tundra from the Kolyma River to the Alazeya River. In 1980 the area of the species’ supposed breeding grounds within the Kolyma- Indigirka interfluve comprised 34,600 km2. In 1984-85, the breeding grounds extended west to the Sundrun River, with the total area reaching 49,400 km2. At present, the westernmost sandhill crane range is on the tundra along the lower reaches of the Berelekh River. This region joins the higher density Siberian crane (G. leucogeranus) range, so that the …

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Summary Of Sandhill Crane Sport Harvest In Canada 1975–2006, Adrianna C. Araya, Kammie L. Kruse, Keith D. Warner Jan 2010

Summary Of Sandhill Crane Sport Harvest In Canada 1975–2006, Adrianna C. Araya, Kammie L. Kruse, Keith D. Warner

Proceedings of the North American Crane Workshop

Knowledge of harvest in all areas where the mid-continent population (MCP) of sandhill cranes (Grus canadensis) occurs is critical to managing the population in a sustainable manner. The harvest of MCP in the U.S. has been well documented; however, the harvest in Canada has received less attention. The Canadian Wildlife Service initiated a National Harvest Survey program in 1967, but all sampling variables were not directly comparable until 1975. In this paper, we summarize crane harvest in Canada during the 1975-2006 hunting seasons for Saskatchewan and Manitoba, the 2 provinces with significant sport hunting harvest of sandhill cranes. …

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Demoiselle Cranes On Agricultural Lands In The Ukraine, Yuriy Andryushchenko Jan 2010

Demoiselle Cranes On Agricultural Lands In The Ukraine, Yuriy Andryushchenko

Proceedings of the North American Crane Workshop

In Eurasia, the western range of the demoiselle crane (Anthropoides virgo) includes the southeast of Ukraine. Here the species nests, forms flying and pre-migrating concentrations, and participates in migration. The number of demoiselle cranes in April-June is about 600-700 individuals (200-250 nesting pairs), and toward the end of the year the population can reach 900-1000 individuals. Of cranes observed during 2000-2008 in the Crimea, 42.3% of pairs (n = 151) nested on agricultural fields: 21.5% on virgin land, 16.1% on cropland, and 3.4% on fallow lands. Principal characteristics of the demoiselle crane nesting locations were wavy relief, scarce herbage, …

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Possible Competition Between Waterfowl And Sandhill Cranes At Hiwassee Wildlife Refuge, Tennessee, David A. Aborn Jan 2010

Possible Competition Between Waterfowl And Sandhill Cranes At Hiwassee Wildlife Refuge, Tennessee, David A. Aborn

Proceedings of the North American Crane Workshop

As a result of crop planting for waterfowl, numbers of eastern greater sandhill cranes (Grus canadensis tabida) staging and overwintering at the Hiwassee Wildlife Refuge in eastern Tennessee have sharply increased over the last 30-40 years. Peak numbers of wintering cranes have reached 14,000, and this large increase in crane numbers raises the possibility that they may be competing with waterfowl for food and space. I examined broad-scale changes in waterfowl numbers using Christmas Bird Count data, as well as small-scale changes using observations of waterfowl numbers and locations in relation to cranes on individual days. Preliminary results …

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Behavior And Habitat Use Of Greater Sandhill Cranes Wintering In East Tennessee, David A. Aborn Jan 2010

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 …

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First Breeding Records And Historical Status Of Sandhill Cranes In New England, Scott M. Melvin Jan 2010

First Breeding Records And Historical Status Of Sandhill Cranes In New England, Scott M. Melvin

Proceedings of the North American Crane Workshop

Sandhill cranes (Grus canadensis) nested at 4 sites in south-central Maine between 2000 and 2008 and at single sites in western Massachusetts and west-central Vermont in 2007 and 2008, continuing their eastward range expansion. Of 13 nests observed, 5 were in a lacustrine marsh, 2 were in a riverine marsh, and 2 were in beaver-impounded palustrine marshes, all dominated by cattail (Typha spp.); 2 were in lacustrine fen habitat dominated by sedges (Carex spp.), sphagnum, and leatherleaf (Chamaedaphne calyculata); 1 was in a lacustrine fen dominated by slender sedge (Carex lasiocarpa …

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Mechanisms Of Habitat Selection Of Reintroduced Whooping Cranes On Their Breeding Range, Kelly J. Maguire, Stanley A. Temple Jan 2010

Mechanisms Of Habitat Selection Of Reintroduced Whooping Cranes On Their Breeding Range, Kelly J. Maguire, Stanley A. Temple

Proceedings of the North American Crane Workshop

We examined several mechanisms that influenced the habitat selection of reintroduced whooping cranes (Grus americana) on their breeding range in the midwestern United States. Visual observations on 56 whooping cranes from 2001 to 2006 provided accurate locations, habitat descriptions, and bird associations. Location information on each bird was mapped to create home range and to describe the habitat. We found evidence that habitat selection in these cranes resulted from multiple mechanisms, including habitat imprinting, philopatry, site tenacity, intra-specific interactions, and environmental stochasticity. The initial home ranges of all cranes contained habitat similar to that in which they were …

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Sandhill Crane Migration Chronology And Behavior In Northwestern Texas, Carroll D. Littlefield Jan 2010

Sandhill Crane Migration Chronology And Behavior In Northwestern Texas, Carroll D. Littlefield

Proceedings of the North American Crane Workshop

Migrant lesser sandhill cranes (Grus canadensis canadensis) were monitored during 1990-2000 in northwestern Texas as flocks were arriving in autumn and departing in spring; cranes were counted as they passed over an observation point 23 km north of Sudan, Lamb County, Texas. Mean flock size was 34.5 (SD ± 32.6) in autumn and 58.2 (SD ± 45.0) in spring. Most autumn migrants (69.6%) passed in the afternoon, whereas in spring 94% migrated in the morning (1000-1200 hr). Peak period of autumn passage was in October (65%), and in spring all observations were in February-March with the peak usually …

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Population Status And Geographic Distribution Of Greater Sandhill Cranes In The Mid-Continent Population, Gary L. Krapu, David A. Brandt Jan 2010

Population Status And Geographic Distribution Of Greater Sandhill Cranes In The Mid-Continent Population, Gary L. Krapu, David A. Brandt

Proceedings of the North American Crane Workshop

Number and geographic distribution of greater sandhill cranes (Grus canadensis tabida) in the mid-continent population (MCP) of sandhill cranes were evaluated. G. c. tabida comprised 7 of 133 (5.3%) individuals of 3 subspecies which projects to 31,579 ± 11,661 (SE) individuals in an estimated spring MCP of 600,000 cranes. From a platform transmitting terminal (PTT)-marked sample representative of the geographic distribution of G. c. tabida, 10 of 13 (77%) settled during the breeding season in east-central Canada/Minnesota, including 4 in northwestern Minnesota, 4 in Manitoba (2 at sites near the Minnesota border), and 2 in Ontario. Three …

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Migration Patterns And Movements Of Sandhill Cranes Wintering In Central And Southwestern Louisiana, Sammy L. King, Aaron R. Pierce, Kent R. Hersey, Nicholas Winstead Jan 2010

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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Countability Of Sandhill Cranes In Aerial Surveys, Douglas H. Johnson, John W. Solberg, Courtney L. Amundson Jan 2010

Countability Of Sandhill Cranes In Aerial Surveys, Douglas H. Johnson, John W. Solberg, Courtney L. Amundson

Proceedings of the North American Crane Workshop

Aerial surveys are used to monitor populations of many wildlife species, including sandhill cranes (Grus canadensis). In addition to the usual problems of detectability (involving both availability and perceptibility), aerial surveys of concentrated animals are subject to countability issues; from a rapidly moving aircraft, observers cannot count or accurately estimate the number of animals in a large group. Calibration is sometimes performed in an effort to adjust aerial counts for incomplete detectability and countability by calculating the ratio of animals actually in a group to the number in the group estimated from the aircraft. Here we explore alternative, …

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Aerial Survey Techniques For Breeding Whooping Cranes, Brian W. Johns Jan 2010

Aerial Survey Techniques For Breeding Whooping Cranes, Brian W. Johns

Proceedings of the North American Crane Workshop

Since the discovery of nesting whooping cranes in Wood Buffalo National Park, the Canadian Wildlife Service has conducted aerial surveys to monitor the population. Aerial survey techniques have varied over the years; however, they have generally followed the techniques used by the author since 1991. The technique involves flying a combination of circular flights and transects over known nesting territories and similar looking marshes likely to contain breeding whooping cranes. These aerial surveys account for nearly 100% of the breeding whooping cranes each year.

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