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Full-Text Articles in Population Biology

Lifestyle Of Shellmound Builders In Brazil (Galley Proofs), Sabine Eggers, C. C. Petronilho, K. Brandt, J. Filippini, Karl J. Reinhard Nov 2008

Lifestyle Of Shellmound Builders In Brazil (Galley Proofs), Sabine Eggers, C. C. Petronilho, K. Brandt, J. Filippini, Karl J. Reinhard

School of Natural Resources: Faculty Publications

The contact of inland and coastal prehistoric groups in Brazil is believed to have been restricted to regions with no geographical barrier, as is the case in the Ribeira de Iguape valley. The inland osteological collection from the riverine shellmound Moraes (5800–4500 BP) represents a unique opportunity to test this assumption for this region. Despite cultural similarities between riverine and coastal shellmounds, important ecological and site distribution differences are expected to impact on lifestyle. The purpose of this study is thus to document and interpret health and lifestyle indicators in Moraes in comparison to coastal shellmound groups. Specifically we test …


Familiarity With Breeding Habitat Improves Daily Survival In Colonial Cliff Swallows, Charles R. Brown, Mary Bomberger Brown, Kathleen R. Brazeal Oct 2008

Familiarity With Breeding Habitat Improves Daily Survival In Colonial Cliff Swallows, Charles R. Brown, Mary Bomberger Brown, Kathleen R. Brazeal

School of Natural Resources: Faculty Publications

One probable cost of dispersing to a new breeding habitat is unfamiliarity with local conditions such as the whereabouts of food or the habits of local predators, and consequently immigrants may have lower probabilities of survival than more experienced residents. Within a breeding season, estimated daily survival probabilities of cliff swallows, Petrochelidon pyrrhonota, at colonies in southwestern Nebraska, USA, were highest for birds that had always nested at the same site, followed by those for birds that had nested there in some (but not all) past years. Daily survival probabilities were lowest for birds that were naive immigrants to …


Phylogeographical Structure And Evolutionary History Of Two Buggy Creek Virus Lineages In The Western Great Plains Of North America, Abinash Padhi, Amy T. Moore, Mary Bomberger Brown, Jerome E. Foster, Martin Pfeffer, Kathryn P. Gaines, Valerie A. O'Brien, Stephanie A. Strickler, Allison E. Johnson, Charles R. Brown Sep 2008

Phylogeographical Structure And Evolutionary History Of Two Buggy Creek Virus Lineages In The Western Great Plains Of North America, Abinash Padhi, Amy T. Moore, Mary Bomberger Brown, Jerome E. Foster, Martin Pfeffer, Kathryn P. Gaines, Valerie A. O'Brien, Stephanie A. Strickler, Allison E. Johnson, Charles R. Brown

School of Natural Resources: Faculty Publications

Buggy Creek virus (BCRV) is an unusual arbovirus within the western equine encephalitis complex of alphaviruses. Associated with cimicid swallow bugs (Oeciacus vicarius) as its vector and the cliff swallow (Petrochelidon pyrrhonota) and house sparrow (Passer domesticus) as its amplifying hosts, this virus is found primarily in the western Great Plains of North America at spatially discrete swallow nesting colonies. For 342 isolates collected in Oklahoma, Nebraska, Colorado, and North Dakota, from 1974 to 2007, we sequenced a 2076 bp region of the 26S subgenomic RNA structural glycoprotein coding region, and analyzed phylogenetic relationships, …


Longevity-Fertility Trade-Offs In The Tephritid Fruit Fly, Anastrepha Ludens, Across Dietary-Restriction Gradients, James R. Carey, Lawrence G. Harshman, Pablo Liedo, Hans-Georg Müller, Jane-Ling Wang, Zhen Zhang Aug 2008

Longevity-Fertility Trade-Offs In The Tephritid Fruit Fly, Anastrepha Ludens, Across Dietary-Restriction Gradients, James R. Carey, Lawrence G. Harshman, Pablo Liedo, Hans-Georg Müller, Jane-Ling Wang, Zhen Zhang

Lawrence G. Harshman Publications

Although it is widely known that dietary restriction (DR) not only extends the longevity of a wide range of species but also reduces their reproductive output, the interrelationship of DR, longevity-extension and reproduction is not well understood in any organism. Here we address the question: “Under what nutritional conditions do the longevity-enhancing effects resulting from food restriction either counteract, complement or reinforce the mortality costs of reproduction? To answer this question we designed a fine-grained DR study involving 4,800 individuals of the tephritid fruit fly Anastrepha ludens in which we measured sex-specific survival and daily reproduction in females in each …


Ecology Of The Missouri River: Missouri River Creel Survey, Bellevue Bridge To Camp Creek, 31 March Through 12 October 2007. Supplement I, Gerald Mestl Mar 2008

Ecology Of The Missouri River: Missouri River Creel Survey, Bellevue Bridge To Camp Creek, 31 March Through 12 October 2007. Supplement I, Gerald Mestl

Nebraska Game and Parks Commission: White Papers, Conference Presentations, and Manuscripts

This report describes Missouri River activities and results related to a channelized Missouri River creel survey conducted from 29 March through 10 October 2003. This is the fourth of a planned annual creel survey to be conducted on alternating sections of the channelized Missouri River to measure changes in recreational fishing activity, especially those changes due to large scale habitat restoration efforts. Future reports will contain additional analyses of these data.

Anglers spent over 30,000 hours fishing the Missouri River from Camp Creek (rk 883.5) to the Kansas state line (rk 790.2) during the survey period. Effort peaked during the …


Population Status , Hunting Regulations , And Harvests Of The Rocky Mountain Population Of Greater Sandhill Cranes, 1981–2005, Kammie L. Kruse, David E. Sharp, James A. Dubovsky Jan 2008

Population Status , Hunting Regulations , And Harvests Of The Rocky Mountain Population Of Greater Sandhill Cranes, 1981–2005, Kammie L. Kruse, David E. Sharp, James A. Dubovsky

Proceedings of the North American Crane Workshop

The Rocky Mountain Population (RMP) of greater sandhill cranes (Grus canadensis tabida) was not hunted in the U.S. from 1916 until 1981, when Arizona initiated the first modern-day season. Hunting programs in the U.S. were subsequently expanded to 6 states for the RMP and have been guided by a cooperative flyway management plan, including a harvest strategy, which has been periodically updated and endorsed by the Central and Pacific Flyway Councils. From a management perspective, 3 population parameters have been identified to monitor the status and health of this population: harvest, recruitment, and population size. The number of …


Management Of Lands Along The Platte River Fromelmcreek To Lexington, Nebraska, As Crane Habitat, James J. Jenniges, Mark M. Peyton Jan 2008

Management Of Lands Along The Platte River Fromelmcreek To Lexington, Nebraska, As Crane Habitat, James J. Jenniges, Mark M. Peyton

Proceedings of the North American Crane Workshop

To meet Federal Energy Regulatory Commission (FERC) license requirements for the operation of 5 hydroelectric power plants on the North Platte and Platte Rivers in Nebraska, the Nebraska Public Power District (NPPD) and The Central Nebraska Public Power and Irrigation District (Central) together have become the second largest owners and managers of lands for the conservation of endangered species and migratory waterbirds along the central reach of the Platte River. We describe here the management activities on the properties, success of the management in achieving objectives, and the response of sandhill (Grus canadensis) and whooping cranes (G. …


New Hunter Education Strategies To Protect Whooping Cranes In Texas And Kansas, Lee Ann Johnson Linam, Helen M. Hands, Jay Roberson Jan 2008

New Hunter Education Strategies To Protect Whooping Cranes In Texas And Kansas, Lee Ann Johnson Linam, Helen M. Hands, Jay Roberson

Proceedings of the North American Crane Workshop

The decline of the whooping crane (Grus americana) has often been attributed primarily to loss of habitat and overharvest. Although hunting of whooping cranes is now prohibited, shootings sometimes occur. Recent incidences have prompted the Texas Parks and Wildlife Department (Texas) and the Kansas Department of Wildlife and Parks (Kansas) to develop new strategies that increase hunter recognition of legal game species and awareness of endangered species concerns. Both agencies have produced or updated publications for goose and sandhill crane (Grus canadensis) hunters. Texas has developed video news releases for the general public and a video/DVD …


The Cuban Sandhill Crane As Umbrella Species: Relationship With Plant Diversity In Threatene D White Sand Savannahs, Duniet Marrero Garcia, Jose A. Osorio, Xiomara Galvez Aguilera, Felipe Chavez-Ramirez Jan 2008

The Cuban Sandhill Crane As Umbrella Species: Relationship With Plant Diversity In Threatene D White Sand Savannahs, Duniet Marrero Garcia, Jose A. Osorio, Xiomara Galvez Aguilera, Felipe Chavez-Ramirez

Proceedings of the North American Crane Workshop

This project describes relationships between the Cuban sandhill crane (Grus canadensis nesiotes) distribution and habitat use and plant diversity in white sand savannahs, a threatened ecosystem in Cuba. Data are based on habitat use and selection of 10 radio-tagged sandhill cranes in the Los Indios Ecological reserve, Isle of Youth. We used Arcview and satellite imagery to map broad vegetation categories. Within the general Pine-Palm savannahs specific plant communities were characterized using species composition and dominant plant life forms. Habitat types most used by cranes for feeding and nesting were also those with highest plant species richness and …


Trends In Sandhill Crane Numbers In Eastern New Mexico, James B. Montgomery Jr. Jan 2008

Trends In Sandhill Crane Numbers In Eastern New Mexico, James B. Montgomery Jr.

Proceedings of the North American Crane Workshop

Following a 1980s decline in the number of cranes in the Bitter Lake National Wildlife Refuge area of the Pecos River Valley in eastern New Mexico, peak fall migration numbers increased from 5,640 in 1989-90 to 15,790 in 2003-04 and 13,650 in 2004-05. Concurrently, hectares of corn grown for silage to feed dairy cows increased from 1,781 in 1989 to 8,013 in 2003 and 7,325 in 2004. The population goals of the NM Department of Game and Fish are being met but a downturn in the dairy industry could result in a decline in crane numbers.


Do We Need Such Rare Birds?, Stephen A. Nesbitt Jan 2008

Do We Need Such Rare Birds?, Stephen A. Nesbitt

Proceedings of the North American Crane Workshop

Gruidae is one of the oldest bird families; the genus Grus dates back at least 9 million years. Though they may have been around a long time, it is unlikely that cranes were ever among the most abundant of birds. Several of the 15 crane species occur today in such low numbers that they are considered in danger of becoming extinct. It has been posited that at the time of European colonization of North America whooping cranes may have numbered 10,000 individuals, so whooping cranes have likely always been rare birds. Rare has often been used as a synonym for …


Timing Of Molt In Florida Sandhill Cranes, Stephen A. Nesbitt, Stephen T. Schwikert Jan 2008

Timing Of Molt In Florida Sandhill Cranes, Stephen A. Nesbitt, Stephen T. Schwikert

Proceedings of the North American Crane Workshop

We observed feather molt in Florida sandhill cranes (Grus canadensis pratensis) between 1978 and 1997. We report data from 4 feather groups: remiges, rectrices, wing coverts and contour feathers. In all feather groups, the median date of ecdysis preceded endysis by about 30 days. Endysis in adults was generally later than it was in first- or second-year subadults. Remiges grew at a rate of 4.72 ± 1.56 SD mm per day. We estimated that primary and secondary wing feathers were usually regenerated within 45 to 70 days.


Safety Of West Nile Virus Vaccines In Sandhill Crane Chicks, Glenn H. Olsen, Kimberli J. Miller, Douglas E. Docherty, Valerie Bochsler Jan 2008

Safety Of West Nile Virus Vaccines In Sandhill Crane Chicks, Glenn H. Olsen, Kimberli J. Miller, Douglas E. Docherty, Valerie Bochsler

Proceedings of the North American Crane Workshop

West Nile virus arrived in North America in 1999 and has spread across the continent in the ensuing years. The virus has proven deadly to a variety of native avian species including sandhill cranes (Grus canadensis). In order to provide safe and efficacious protection for captive and released populations of whooping cranes (G. americana), we have conducted a series of four research projects. The last of these was a study of the effects of two different West Nile virus vaccines on young Florida sandhill crane (G. c. pratensis) chicks and subsequent challenge with the virus. …


Common Crane Management In Germany -Monitoring, Protection, And Scientific Work, Hartwig Prange Jan 2008

Common Crane Management In Germany -Monitoring, Protection, And Scientific Work, Hartwig Prange

Proceedings of the North American Crane Workshop

About 200,000 common cranes (Grus grus) from northern, middle, and northeastern parts of Europe are migrating on the West-European route. In the northeast part of Germany 160,000 cranes stop over simultaneously during migration. This number has increased since the early 1980´s by 3-fold. About 60 sites with from 200 to 50,000 cranes are systematically observed from August to December by local expert groups. The overnight roosts are in ponds, swamps, and lakes, actively flooded meadows, and brown coal mines as well as in shallow backwaters of the Baltic Sea. They have been used year after year. More than …


A Low Intensity Sampling Method For Assessing Blue Crab Abundance At Aransas National Wildlife Refuge And Preliminary Results On The Relationship Of Blue Crab Abundance To Whooping Crane Winter Mortality, Bruce H. Pugesek, Michael J. Baldwin, Thomas V. Stehn Jan 2008

A Low Intensity Sampling Method For Assessing Blue Crab Abundance At Aransas National Wildlife Refuge And Preliminary Results On The Relationship Of Blue Crab Abundance To Whooping Crane Winter Mortality, Bruce H. Pugesek, Michael J. Baldwin, Thomas V. Stehn

Proceedings of the North American Crane Workshop

We sampled blue crabs (Callinectes sapidus) in marshes on the Aransas National Wildlife Refuge, Texas from 1997 to 2005 to determine whether whooping crane (Grus americana) mortality was related to the availability of this food source. For four years, 1997 - 2001, we sampled monthly from the fall through the spring. From these data, we developed a reduced sampling effort method that adequately characterized crab abundance and reduced the potential for disturbance to the cranes. Four additional years of data were collected with the reduced sampling effort methods. Yearly variation in crab numbers was high, ranging …


Reproductive Health Of The Florida Flock Of Introduced Whooping Cranes, Marilyn G. Spalding, Martin J. Folk, Stephen A. Nesbitt Jan 2008

Reproductive Health Of The Florida Flock Of Introduced Whooping Cranes, Marilyn G. Spalding, Martin J. Folk, Stephen A. Nesbitt

Proceedings of the North American Crane Workshop

We examined the reproductive parameters of the introduced non-migratory flock of whooping cranes in Florida. Of 289 cranes introduced, 67 males and 65 females survived at least 3 years. The first behavioral pairs appeared in 1995, and eggs were first laid in 1999. In total, eggs were laid in 47 nests, 17 chicks hatched, and 4 young fledged by 2005. Severe drought conditions through 2001 were thought to be the reason for low reproductive nest success. In 2003 nesting conditions improved and 71% of nests with eggs, hatched chicks. During the next 2 years, with continued wet conditions, the proportion …


Aerial Census Techniques For Whooping Cranes On The Texas Coast, Thomas V. Stehn, Thomas E. Taylor Jan 2008

Aerial Census Techniques For Whooping Cranes On The Texas Coast, Thomas V. Stehn, Thomas E. Taylor

Proceedings of the North American Crane Workshop

The U.S. Fish and Wildlife Service, using aerial surveys, regularly monitors the whooping crane (Grus americana) population wintering along the Texas coast. These regular census flights began in 1950 and have produced a long-term data set on the growth of a small population of endangered birds. This paper describes the specific methodology used by the authors during census flights.


Survival, Movements, Social Structure, And Reproductive Behavior During Development Of A Population Of Reintroduced, Migratory Whooping Cranes, Richard P. Urbanek, Lara E. A. Fondow Jan 2008

Survival, Movements, Social Structure, And Reproductive Behavior During Development Of A Population Of Reintroduced, Migratory Whooping Cranes, Richard P. Urbanek, Lara E. A. Fondow

Proceedings of the North American Crane Workshop

An effort to reintroduce a migratory population of whooping cranes (Grus americana) into eastern North America began in 2001. During 2001-2004, 53 juveniles were released. All chicks were hatched at Patuxent Wildlife Research Center, Maryland, and transferred to Necedah National Wildlife Refuge (NWR), Wisconsin. Chicks were costume/isolation-reared and, with few exceptions, trained to follow ultralight aircraft, which led them to Chassahowitzka NWR, Central Gulf Coast of Florida. All individuals successfully returned to Central Wisconsin during their first spring migration except for the following: 5 individuals that were unable to navigate around Lake Michigan after taking an easterly migration …


Experimental Inoculation Of House Sparrows (Passer Domesticus) With Buggy Creek Virus, Kathryn P. Huyvaert, Amy T. Moore, Nicholas A. Panella, Eric A. Edwards, Mary Bomberger Brown, Nicholas Komar, Charles R. Brown Jan 2008

Experimental Inoculation Of House Sparrows (Passer Domesticus) With Buggy Creek Virus, Kathryn P. Huyvaert, Amy T. Moore, Nicholas A. Panella, Eric A. Edwards, Mary Bomberger Brown, Nicholas Komar, Charles R. Brown

School of Natural Resources: Faculty Publications

We performed experimental inoculations of house sparrows (Passer domesticus) with Buggy Creek virus (BCRV), a poorly known alphavirus (Togaviridae) vectored primarily by the swallow bug (Hemiptera: Cimicidae: Oeciacus vicarius) that is an ectoparasite of the cliff swallow (Petrochelidon pyrrhonota) and house sparrow. Viremias were detected by plaque assay in two of six birds on days 1–3 postinoculation; viremia was highest on day 2. Viral RNA was detected by reverse transcriptase-polymerase chain reaction (RT-PCR) in blood of six of 12 birds ranging from day 1 to day 15 postinoculation. Infectious BCRV was detected in …


Temporal Distribution Of Harvested Mid-Continent Sandhill Cranes Within The Central Flyway States During The 1997-2001 Hunting Seasons, Adrianna C. Araya, James A. Dubovsky Jan 2008

Temporal Distribution Of Harvested Mid-Continent Sandhill Cranes Within The Central Flyway States During The 1997-2001 Hunting Seasons, Adrianna C. Araya, James A. Dubovsky

Proceedings of the North American Crane Workshop

Since 1975, annual harvest estimates for Mid-Continent sandhill cranes (Grus canadensis) have been collected in all states for which a hunting season has been authorized by the U.S. Fish and Wildlife Service (Service). Although these data have been used to monitor the harvest of the Mid-Continent population, analyses to promote understanding of the temporal distribution of harvested sandhill cranes by individual states throughout the Central Flyway have not been conducted. For the 1997-2001 hunting seasons, we collected harvest questionnaires from 4,408 hunters in the Central Flyway who provided information about the date, location, and number of harvested sandhill …


Infectious Bursal Disease In Wild Populations Of Turkeys And Sandhill Cranes: Preliminary Findings, Kristen L. Candelora, Marilyn G. Spalding, Stephen A. Nesbitt, Holly S. Sellers, Jeremy Olson, Larry Perrin, Jeannette Parker Jan 2008

Infectious Bursal Disease In Wild Populations Of Turkeys And Sandhill Cranes: Preliminary Findings, Kristen L. Candelora, Marilyn G. Spalding, Stephen A. Nesbitt, Holly S. Sellers, Jeremy Olson, Larry Perrin, Jeannette Parker

Proceedings of the North American Crane Workshop

Captive-reared whooping cranes (Grus americana) released into Florida for the resident reintroduction project experienced unusually high mortality and morbidity during the 1997-1998 and 2001-2002 release seasons (Spalding et al. 2008). Infectious bursal disease virus (IBDV) serotype 2 is currently under investigation as the factor that precipitated the mortality events. A small percentage of whooping cranes have been exposed to IBDV in the captive setting. However, many more are being exposed postrelease, and prevalence of exposure seems to increase with age or length of time the birds are in the wild in Florida (Spalding et al. 2008). The goals …


Proceedings Of The Tenth North American Crane Workshop: Cover, Preface, Contents Jan 2008

Proceedings Of The Tenth North American Crane Workshop: Cover, Preface, Contents

Proceedings of the North American Crane Workshop

Every 3 years (or thereabouts), the North American Crane Working Group holds a workshop for the exchange of information regarding efforts to conserve and better understand America’s two cranes. The papers herein, with a few exceptions, were presented in Zacatecas City, Zacatecas, Mexico 7-10 February 2006 at the Tenth North American Crane Workshop. When preparing for a trip to Mexico in February, visions of sunny beaches come first to mind. However the city of Zacatecas is over 8,000 feet above sea level, so nights were often chilly and the altitudinal changes took a while for us flatlanders to adjust to. …


Current Status Of Nonmigratory Whooping Cranes In Florida, Martin J. Folk, Stephen A. Nesbitt, Jeannette M. Parker, Marilyn G. Spalding, Stephen B. Baynes, Kristen L. Candelora Jan 2008

Current Status Of Nonmigratory Whooping Cranes In Florida, Martin J. Folk, Stephen A. Nesbitt, Jeannette M. Parker, Marilyn G. Spalding, Stephen B. Baynes, Kristen L. Candelora

Proceedings of the North American Crane Workshop

Two hundred eighty-nine nonmigratory whooping cranes (Grus americana) were released in Central Florida from 1993-2005. As of January 2006, we had monitored 50 birds (16 pairs) but suspect 10 others had also survived, for a population estimate of 60 birds. The sex ratio for monitored birds was 1:1. From 47 nest attempts (1999-2005), only 4 chicks have fledged and survived to independence. Efforts are underway to determine why recruitment has been lower than expected. Other challenges for the project have included birds colliding with power lines, dispersing beyond their normal range (beyond Florida), forming pair bonds with Florida sandhill cranes …


Feather Molt Of Nonmigratory Whooping Cranes In Florida, Martin J. Folk, Stephen A. Nesbitt, Jeannette M. Parker, Marilyn G. Spalding, Stephen B. Baynes, Kristen L. Candelora Jan 2008

Feather Molt Of Nonmigratory Whooping Cranes In Florida, Martin J. Folk, Stephen A. Nesbitt, Jeannette M. Parker, Marilyn G. Spalding, Stephen B. Baynes, Kristen L. Candelora

Proceedings of the North American Crane Workshop

Molt patterns of wild whooping cranes (Grus americana) are largely unknown, and what knowledge we have has been based on scant data. We documented patterns of feather molt in nonmigratory whooping cranes in Florida during 1993-2005. All birds replaced flight feathers (remiges) in a synchronous (simultaneous) manner and spent time flightless. It took 38-46 days (mean = 44 days, n = 8) for feathers to regrow and birds to regain flight ability. When flightless due to remigial molt, cranes became more secretive and spent more time in wetlands during feather regrowth. Most (70%) whooping cranes first molted their …


Reduction Of Crop Depredations By Cranes At Daursky State Biosphere Reserve, Siberia, Oleg A. Goroshko, John E. Cornely, Stephen H. Bouffard Jan 2008

Reduction Of Crop Depredations By Cranes At Daursky State Biosphere Reserve, Siberia, Oleg A. Goroshko, John E. Cornely, Stephen H. Bouffard

Proceedings of the North American Crane Workshop

The Daursky State Biosphere Reserve (SBR) in southern Siberia includes the Torey Lakes, the largest lakes in the Trans-Baikal region. The Torey Lakes support tens of thousands of breeding waterbirds and about a million waterbirds during migration. Peak numbers of birds staging during fall coincide with grain harvest. Crop fields around the Torey Lakes attract 50,000 to 70,000 waterbirds, primarily cranes with lesser numbers of waterfowl, causing significant crop damage in fields near Daursky SBR. Investigations of the problem have been ongoing since 1992. Field consultation by Cornely and Bouffard in 2001 resulted in recommendations to reduce depredations. The consultation …


Serological Survey For Infectious Bursal Disease Virus Ex Posure In Captive Cranes, Barry K. Hartup, Holly S. Sellers Jan 2008

Serological Survey For Infectious Bursal Disease Virus Ex Posure In Captive Cranes, Barry K. Hartup, Holly S. Sellers

Proceedings of the North American Crane Workshop

Between September 2001 and March 2002, unusually high morbidity and mortality was observed during releases of endangered, captive-reared whooping cranes (Grus americana) in central Florida. An ongoing epidemiological investigation has implicated infectious bursal disease virus (IBDV; Family Birnaviridae) as the likely etiological agent (Spalding et al. 2008). The source of this virus remains unknown. A previous serological survey showed positive antibody titers to IBDV serotype 2 were present in small numbers of juvenile and adult whooping cranes at the International Crane Foundation (ICF), Baraboo, Wisconsin and the Patuxent Wildlife Research Center, Laurel, Maryland between 1995 and 2003 (Hartup et al. …


Factors Influencing Greater Sandhill Crane Nest Success At Malheur National Wildlife Refuge, Oregon, Gary L. Ivey, Bruce D. Dugger Jan 2008

Factors Influencing Greater Sandhill Crane Nest Success At Malheur National Wildlife Refuge, Oregon, Gary L. Ivey, Bruce D. Dugger

Proceedings of the North American Crane Workshop

We used logistic regression to model the effects of weather, habitat, and management variables on Greater Sandhill Crane (Grus canadensis tabida) nest success at Malheur National Wildlife Refuge in southeast Oregon. We monitored 506 nests over 9 breeding seasons. Mean apparent nest success was 72% ± 4% and varied from 51 to 87%. Nest success was lower one year after a field was burned and declined with nest initiation date. Nest success was higher during warmer springs, in deeper water, and in years with moderate precipitation. Haying, livestock grazing, and predator control did not influence nest success. We …


Responses Ofnesting Sandhill Cranes To Research Activities And Effects On Nest Survival, Jane E. Austin, Deborah A. Buhl Jan 2008

Responses Ofnesting Sandhill Cranes To Research Activities And Effects On Nest Survival, Jane E. Austin, Deborah A. Buhl

Proceedings of the North American Crane Workshop

We examined the response of nesting greater sandhill cranes (Grus canadensis tabida) to research-related activities at Grays Lake, Idaho, during 1997–2000. Data were collected on >500 crane nests from 53 fields that were exposed to variable levels of research activity, from fields subjected to only periodic searches for and monitoring of crane nests (crane-only fields) to fields subjected to periodic searches for and monitoring of all waterbird nests as well as breeding bird surveys, nocturnal amphibian surveys, and other research-related activities (multi-use fields). For each nest, we calculated the visit rate to the field during the period the …


Is Magnitude Of Fat Storage By Spring-Staging Sandhill Cranes Declining In The Central Platte River Valley , Nebraska?, David A. Brandt, Gary L. Krapu Jan 2008

Is Magnitude Of Fat Storage By Spring-Staging Sandhill Cranes Declining In The Central Platte River Valley , Nebraska?, David A. Brandt, Gary L. Krapu

Proceedings of the North American Crane Workshop

Proximate analyses of carcasses of sandhill cranes (Grus canadensis) collected in the Central Platte River Valley (CPRV), Nebraska, during spring 1999 indicated a marked decline in fat levels from springs 1978 and 1979. Concern that amounts of fat cranes stored by their spring departures from the CPRV may have further declined prompted this evaluation. For our assessment, we made use of morphological measurements (culmen post nares, tarsus, flattened wing chord) along with body mass on each of 810 sandhill cranes that were collected for proximate analysis or captured with rocket nets at widely distributed sites in the CPRV during 1978-1979 …


Temporal Dynamics And Flock Characteristics Of Sandhill Cranes In The Platte River Valley , Nebraska, Felipe Chavez-Ramirez Jan 2008

Temporal Dynamics And Flock Characteristics Of Sandhill Cranes In The Platte River Valley , Nebraska, Felipe Chavez-Ramirez

Proceedings of the North American Crane Workshop

I gathered information on crane flocks in the Platte River Valley during spring staging of 2002-2004. The objective of
this work was to evaluate hypotheses regarding flock size and formation using sandhill crane (Grus canadensis) flocks observed in
the Platte River Valley. Specifically, I wanted to: (a) evaluate the effect of period of migration, geographical location, and habitat
type on flock size, and (b) evaluate predictions regarding ecological theories of flock formation and behavior based on concentrated
resources, accessibility, social facilitation, and potential predation response. Flock size overall was influenced negatively by period
of migration (P < 0.001) and positively by geographical location (P < 0.01). Total crane abundance (55%) of flocks were located
in corn fields, but …