Open Access. Powered by Scholars. Published by Universities.®

Population Biology Commons™

Open Access. Powered by Scholars. Published by Universities.®

Ornithology

Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 451 - 480 of 703

Full-Text Articles in Population Biology

Behavior Comparisons For Whooping Cranes Raised By Costumed Caregivers And Trained For An Ultralight-Led Migration, Glenn H. Olsen, John B. French Jan 2008

Behavior Comparisons For Whooping Cranes Raised By Costumed Caregivers And Trained For An Ultralight-Led Migration, Glenn H. Olsen, John B. French

Proceedings of the North American Crane Workshop

The successful reintroduction program being run by the Whooping Crane Eastern Partnership using whooping cranes (Grus americana) trained to fly behind ultralight aircraft depends on a supply of these trained crane colts each year. The crane colts are hatched from eggs contributed by the various partners and trained to follow costume clad humans and ultralight aircraft at USGS Patuxent Wildlife Research Center, Laurel, Maryland, USA. After several seasons of raising small numbers of crane colts (7-14), we wanted to increase the number of birds being trained, but were restrained by limits in our facilities. By altering the established …

Go to article

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. …

Go to article

Use Of Clap Traps In Capturing Nonmigratory Whooping Cranes In Florida, Jeannette M. Parker, Martin J. Folk, Stephen B. Baynes, Kristen L. Candelora Jan 2008

Use Of Clap Traps In Capturing Nonmigratory Whooping Cranes In Florida, Jeannette M. Parker, Martin J. Folk, Stephen B. Baynes, Kristen L. Candelora

Proceedings of the North American Crane Workshop

Between March 2001 and April 2005 we captured 28 nonmigratory Florida whooping cranes (Grus americana) with clap traps. Out of the 6 different capture methods we employed, the clap trap accounted for 42% of our birds captured. Its ability to safely capture one crane or multiple cranes simultaneously, flexibility in size and placement, and low cost make it an important tool to facilitate transmitter replacements and health checks among the experimental Florida whooping crane population.

Go to article

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 …

Go to article

Whooping Crane Collisions With Power Lines: An Issue Paper, Thomas V. Stehn, Tom Wassenich Jan 2008

Whooping Crane Collisions With Power Lines: An Issue Paper, Thomas V. Stehn, Tom Wassenich

Proceedings of the North American Crane Workshop

Collision with power lines is the greatest source of mortality for fledged whooping cranes (Grus americana) in the Aransas-Wood Buffalo population (AWBP) that migrate between the Northwest Territories, Canada to the Texas coast. This paper compiles 45 documented whooping crane mortalities from power line strikes in North America and provides known information on crane / power line interactions. A map of the AWBP whooping crane migration corridor was derived with 100 and 200-mile wide corridors delineated showing the location of known mortalities. Recommendations are provided to try to reduce this major threat facing whooping cranes.

Go to article

A Year-Long Study Of Food Consumption By Captive Whooping Cranes At The International Crane Foundation, Jessica J. Stocking, Michael S. Putnam, Nathanial B. Warning Jan 2008

A Year-Long Study Of Food Consumption By Captive Whooping Cranes At The International Crane Foundation, Jessica J. Stocking, Michael S. Putnam, Nathanial B. Warning

Proceedings of the North American Crane Workshop

Throughout 2002, we recorded daily food consumption by 12 pairs of captive whooping cranes (Grus americana). For 7 pairs we recorded food consumption throughout the entire year while there were large continuous gaps in measurements of food consumption for 5 pairs that raised chicks that year. Birds received both a maintenance and breeder diet, and for both we converted food consumption to energy intake (Joules/g body mass) using the combined fall weights of female and male. We compared daily energy intake with 6 meteorological variables (involving temperature, wind speed and humidity), photoperiod (natural and artificial) and egg laying …

Go to article

Resolutions Passed By The North American Crane Working Group, Tenth North American Crane Workshop Zacatecas City, Zacatecas, Mexico, North American Crane Working Group Jan 2008

Resolutions Passed By The North American Crane Working Group, Tenth North American Crane Workshop Zacatecas City, Zacatecas, Mexico, North American Crane Working Group

Proceedings of the North American Crane Workshop

Florida Crane habitat resolution
Florida has the largest population of non-migratory sandhill cranes in the world and winters a significant portion of the eastern population of greater sandhill cranes. And in Florida, efforts are underway to introduce migratory and non-migratory whooping cranes. In order to successfully establish and sustain these populations, appropriate habitat needs to be available. About 40% of Florida’s best crane habitat has been lost between 1973 and 2003, and the amount has increased since then. Because of this, these valuable populations of cranes are finding it more difficult to locate suitable habitat. We the NACWG by this …

Go to article

Lifetime Reproductive Success Of Female Eastern Kingbirds (Tyrannus Tyrannus): Influence Of Lifespan, Nest Predation And Body Size, Michael T. Murphy Jul 2007

Lifetime Reproductive Success Of Female Eastern Kingbirds (Tyrannus Tyrannus): Influence Of Lifespan, Nest Predation And Body Size, Michael T. Murphy

Biology Faculty Publications and Presentations

I report on the lifetime reproductive success (LRS) of female Eastern Kingbirds (Tyrannus tyrannus) in central New York. I investigated the major correlates of LRS and specifi cally tested the hypothesis that small body size yields reproductive benefi ts. Lifetime reproductive success varied widely: 15–20% of females failed to fledge young over their life, whereas 50% of young were fledged by 20% of females. Female lifespan varied between one and eight years, and females that died after one breeding season tended to be smaller-bodied than long-lived females (≥2 seasons). I therefore conducted analyses of LRS for the entire sample and …

Go to article

A Molecular Evaluation Of The North American “Grassland” Sparrow Clade, John Klicka, Garth M. Spellman Apr 2007

A Molecular Evaluation Of The North American “Grassland” Sparrow Clade, John Klicka, Garth M. Spellman

Ornithology Program (HRC)

Because they share several morphological and ecological characters, the North American sparrow (Emberizidae) genera Ammodramus, Passerculus, and Xenospiza have historically been considered members of a well-defined “grassland” sparrow assemblage. Relationships among the 11 members of this group have been the subject of much taxonomic debate, yet no comprehensive molecular assessment of relationships has been done. We investigated these relationships using mitochondrial DNA sequence data that included complete cytochrome-b and ND2 genes. Phylogenetic reconstructions derived via parsimony, likelihood, and Bayesian methods were congruent. The grassland sparrows, as presently configured, are polyphyletic. Pooecetes gramineus, Amphispiza belli (but not A. …

Go to article

Bird Movement Predicts Buggy Creek Virus Infection In Insect Vectors, Charles R. Brown, Mary Bomberger Brown, Amy T. Moore, Nicholas Komar Jan 2007

Bird Movement Predicts Buggy Creek Virus Infection In Insect Vectors, Charles R. Brown, Mary Bomberger Brown, Amy T. Moore, Nicholas Komar

School of Natural Resources: Faculty Publications

Predicting the spatial foci of zoonotic diseases is a major challenge for epidemiologists and disease ecologists. Migratory birds are often thought to be responsible for introducing some aviozoonotic pathogens such as West Nile and avian influenza viruses to a local area, but most information on how bird movement correlates with virus prevalence is anecdotal or indirect. We report that the prevalence of Buggy Creek virus (BCRV) infection in cimicid swallow bugs (Oeciacus vicarius), the principal invertebrate vector for this virus, was directly associated with the likelihood of movement by cliff swallows (Petrochelidon pyrrhonota), an amplifying host …

Go to article

Ecological Correlates Of Buggy Creek Virus Infection In Oeciacus Vicarius, Southwestern Nebraska, 2004, Amy T. Moore, Eric A. Edwards, Mary Bomberger Brown, Nicholas Komar, Charles R. Brown Jan 2007

Ecological Correlates Of Buggy Creek Virus Infection In Oeciacus Vicarius, Southwestern Nebraska, 2004, Amy T. Moore, Eric A. Edwards, Mary Bomberger Brown, Nicholas Komar, Charles R. Brown

School of Natural Resources: Faculty Publications

Buggy Creek virus (family Togaviridae, genus Alphavirus, BCRV) is an alphavirus within the western equine encephalitis virus complex whose primary vector is the swallow bug, Oeciacus vicarius Horvath (Hemiptera: Cimicidae), an ectoparasite of the colonially nesting cliff swallow, Petrochelidon pyrrhonota, that is also a frequent host for the virus.We investigated ecological correlates of BCRV infection in 100-bug pools at 14 different swallow colony sites in southwestern Nebraska from summer 2004, by using plaque assay on Vero cells to identify cytopathic virus and reverse transcription-polymerase chain reaction to identify noncytopathic viral RNA. We found 26.7% of swallow bug pools …

Go to article

First Records And First Proven Breeding Of Lesser Grey Shrike, Lanius Minor, In Mongolia, Markus Deutsch, Axel Bräunlich Jan 2007

First Records And First Proven Breeding Of Lesser Grey Shrike, Lanius Minor, In Mongolia, Markus Deutsch, Axel Bräunlich

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

During a trip to the Dzungarian Gobi in southwestern Mongolia, a group of German birdwatchers found several territorial lesser grey shrikes, Lanius minor, and documented an active nest. The species had not previously been recorded from Mongolia. Observations were made near Bulgan gol (Bulgan river; nest coordinates: 46°6’N 91°32’E, 1190 m a.s.l.) in Khovd aimag (Khovd province) on June 24, 2006. Besides two territorial pairs, of which a female could be photographically documented on the nest, at least four more territorial adults were found within an area of about 1.5 km2. Based on these records, an abundance …

Go to article

Estimates Of Breeding Bird Populations In The Sheyenne National Grassland, North Dakota, Mary Ann Cunningham, Douglas Johnson, Daniel N. Svingen Mar 2006

Estimates Of Breeding Bird Populations In The Sheyenne National Grassland, North Dakota, Mary Ann Cunningham, Douglas Johnson, Daniel N. Svingen

The Prairie Naturalist

We conducted a two-year survey of breeding birds in the Sheyenne National Grassland, North Dakota, to estimate total populations of breeding birds. The Grassland is of interest because it provides wildlife habitat and recreational birding opportunities. Indicated breeding pairs were counted on 100-m wide belt transects during morning surveys from late May to early July in 2002 and 2003. We surveyed approximately 6 to 7% of the Grassland each year. The most abundant species in both years were grasshopper sparrow (Ammodramus savannarum), red-winged blackbird (Agelaius phoeniceus), claycolored sparrow (Spizella pallida), Savannah sparrow (Passerculus …

Go to article

The Winter Ecology Of The Piping Plover (Charadrius Melodus) In Coastal Georgia, Brandon Lennon Noel Jan 2006

The Winter Ecology Of The Piping Plover (Charadrius Melodus) In Coastal Georgia, Brandon Lennon Noel

College of Graduate Studies: Theses & Dissertations

Author's abstract: The Piping Plover (Charadrius melodus) is a federally listed species with three distinct breeding populations, including Great Plains (threatened), Great Lakes (endangered), and Atlantic Coast (threatened), all of which winter along the Atlnatic and Gulf coasts of the United States. I studied the winter ecology of the Piping Plovers on Little St. Simons Island (LSSI), Georgia, from 2003-2006, with emphasis on the conservation significance of this site for the endangered Great Lakes population. During 2003-2004 and 2004-2005, LSSI supported up to 100 Piping Plovers during peak migration, and approximately 40 birds wintered at this site. All populations had …

Go to article

Use Of Wading Birds As Indicators Of Potential Whooping Crane Wintering Habitat, Dawn A. Sherry, Felipe Chavez-Ramirez Jan 2005

Use Of Wading Birds As Indicators Of Potential Whooping Crane Wintering Habitat, Dawn A. Sherry, Felipe Chavez-Ramirez

Proceedings of the North American Crane Workshop

A search for suitable wintering sites on which to establish another migratory population of whooping crane (Grus americana) has been conducted and will continue. In addition to an evaluation of food availability for whooping cranes, wading birds that overlap highly in patterns of habitat utilization with whooping cranes may be useful as indirect indicators of suitable whooping crane habitat. We determined the extent to which several species of wading birds overlap in patterns of habitat utilization with whooping cranes on their current wintering grounds. We conducted aerial surveys of whooping cranes and wading birds at Aransas and Matagorda …

Go to article

Patterns Of Relationships Among Whooping Crane Fitness, Blue Crab Abundance, And Freshwater Inflows: An Exploratory Assessment Of Available Data Sets, Felipe Chavez-Ramirez Jan 2005

Patterns Of Relationships Among Whooping Crane Fitness, Blue Crab Abundance, And Freshwater Inflows: An Exploratory Assessment Of Available Data Sets, Felipe Chavez-Ramirez

Proceedings of the North American Crane Workshop

This paper evaluates the possible relationships of whooping crane (Grus americana) fitness parameters to blue crab abundance and freshwater inflows based on independently gathered data sets from several agencies between 1978 and 1999. I ordered all possible analysis models into two separate types based primarily on implied relationships. The 1st order exploratory relationship models were those where evaluated parameters were potentially affected by freshwater inflows, such as salinity and blue crab abundance. The 2nd order exploratory relationship models evaluated parameters that could, more directly, have potential affects on whooping crane fitness parameters for which there was data available. Freshwater inflow …

Go to article

Do Arctic-Nesting Geese Compete With Sandhill Cranes For Waste Corn In The Central Platte River Valley, Nebraska?, Gary L. Krapu, David A. Brandt, Robert R. Cox Jr. Jan 2005

Do Arctic-Nesting Geese Compete With Sandhill Cranes For Waste Corn In The Central Platte River Valley, Nebraska?, Gary L. Krapu, David A. Brandt, Robert R. Cox Jr.

Proceedings of the North American Crane Workshop

Numbers of arctic-nesting geese staging in spring in the Central Platte River Valley (CPRV) of southcentral Nebraska increased dramatically from the 1970s to the 1990s, raising concerns that geese may be competing with the mid-continental population of sandhill cranes (Grus canadensis) for waste corn. From late February to mid-April 1998-2001, we measured temporal patterns of cropland use, evaluated habitat preferences, and compared numbers of geese using the primary crane-occupied parts of the CPRV area with numbers of sandhill cranes. Numbers of Canada geese (Branta canadensis), lesser snow geese (Chen caerulescens)/ Ross’ geese (Chen …

Go to article

Greater Sandhill Crane: Research And Management In California Since 1978, Ronald W. Schlorff Jan 2005

Greater Sandhill Crane: Research And Management In California Since 1978, Ronald W. Schlorff

Proceedings of the North American Crane Workshop

The greater sandhill crane (Grus canadensis tabida) was added to the California list of threatened species in 1983, and the subspecies has been the subject of research and management actions instituted by the California Department of Fish and Game (hereafter Department). Since 1978, the Department has conducted research and recovery actions including periodic breeding ground and wintering area studies, population monitoring, participated in developing Pacific Flyway crane management plans, acquisition and management of key habitats on breeding and wintering grounds, and developed a draft greater sandhill crane recovery strategy. These tasks were accomplished with the assistance of crane …

Go to article

Historical Notes On Whooping Cranes At White Lake, Louisiana: The John J. Lynch Interviews, 1947–1948, Gay M. Gomez, Roderick C. Drewien, Mary Lynch Courville Jan 2005

Historical Notes On Whooping Cranes At White Lake, Louisiana: The John J. Lynch Interviews, 1947–1948, Gay M. Gomez, Roderick C. Drewien, Mary Lynch Courville

Proceedings of the North American Crane Workshop

In May 1939 biologist John J. Lynch of the U.S. Bureau of Biological Survey conducted an aerial survey that documented the existence of a non-migratory population of whooping cranes (Grus americana) near White Lake in southwest Louisiana. Lynch found 13 cranes, including 2 pre-fledged young, confirming breeding. Lynch’s survey occurred, in part, because fur trappers and alligator hunters working in the White Lake marshes had informed the biologist of the cranes’ presence and habits. Lynch continued his contacts with these knowledgeable marsh users, and in 1947 and 1948 interviewed at least 7 individuals. In 2001, M. L. Courville, …

Go to article

Whooping Crane Titers To Eastern Equine Encephalitis Vaccinations, Glenn H. Olsen, Erin Kolski, Jeff S. Hatfield, Douglas E. Docherty Jan 2005

Whooping Crane Titers To Eastern Equine Encephalitis Vaccinations, Glenn H. Olsen, Erin Kolski, Jeff S. Hatfield, Douglas E. Docherty

Proceedings of the North American Crane Workshop

In 1984 an epizootic of eastern equine encephalitis (EEE) virus killed 7 of 39 (18%) whooping cranes in captivity at the Patuxent Wildlife Research Center in Laurel, Maryland, USA. Since that time whooping cranes have been vaccinated with a human EEE vaccine. This vaccine was unavailable for several years, necessitating use of an equine vaccine in the cranes. This study compared the antibody titers measured for three years using the human vaccine with those measured for two years using the equine form. Whooping cranes developed similarly elevated titers in one year using the human vaccine and both years using the …

Go to article

Age, Sex, And Aggression In Florida Sandhill Cranes, Stephen A. Nesbitt Jan 2005

Age, Sex, And Aggression In Florida Sandhill Cranes, Stephen A. Nesbitt

Proceedings of the North American Crane Workshop

Individually directed aggressive interactions were recorded for sandhill cranes in Florida over a 9-year period. Charges and stabs were the most frequently observed aggressive behaviors. Paired adults initiated most of the encounters. Males directed 67% of aggressive interactions toward other males and 84% of female aggressive interactions were directed toward other females. The sex of initiator was significantly correlated with the sex of the receiver (P = 0.001). Paired adults directed most aggression (64.7%) toward other paired adults. Aggression initiated by subadult cranes was directed toward adults and subadults with equal frequency. The aggressiveness in males as an indicator of …

Go to article

The Status Of The Common Crane (Grus Grus) In Europe: Breeding, Resting, Migration, Wintering, And Protection, Hartwig Prange Jan 2005

The Status Of The Common Crane (Grus Grus) In Europe: Breeding, Resting, Migration, Wintering, And Protection, Hartwig Prange

Proceedings of the North American Crane Workshop

At present, about 160,000 and 100,000 cranes are migrating on the West-European and on the Baltic-Hungarian routes, respectively, from the northern, middle, and northeastern parts of Europe. On both routes, the resting maxima, simultaneously determined since the 1980’s, has increased three-fold. This increase in migratory cranes is the result of shorter migration routes with higher return rates, a growing passage from the northwestern part of Russia beginning in the 1990’s, and a protected status in the European Union at breeding as well as at many resting and wintering sites. Hence, the cranes learn to find and use new breeding and …

Go to article

Proceedings Of The Ninth North American Crane Workshop: Preface, Dedications, And Awards Jan 2005

Proceedings Of The Ninth North American Crane Workshop: Preface, Dedications, And Awards

Proceedings of the North American Crane Workshop

These proceedings include papers presented at the Ninth North American Crane Workshop in Sacramento, California in 2003. In addition, there are a few other papers included in this volume of the proceedings that were not presented at the workshop but were appropriate to include here. I would like to thank previous editors of the proceedings Dave and Cathy Ellis and Richard Urbanek for providing advice and suggestions for dealing with the current proceedings. Others provided input and suggestions and they were all well received and appreciated. I want to thank the associate editors of this issue of the proceedings and …

Go to article

Crop Depredations By Cranes At Daursky State Biosphere Reserve, Siberia, Stephen H. Bouffard, John E. Cornely, Oleg A. Goroshko Jan 2005

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

Proceedings of the North American Crane Workshop

Crop depredations by staging cranes have been an annual problem at Daursky State Biosphere Reserve in southern Siberia. In September 2001 we met at Daursky when crane populations peaked to investigate the problem and suggest methods to reduce damages. Peak of crane staging coincided with grain harvest. We counted ≈ 30,000 cranes of 5 species, primarily demoiselles (Anthropoides virgo), in the area. Poor grain yields and cooperative farming systems discouraged efforts to reduce damage. Moving crops further from roost areas may be the most reasonable short term control method, but it’s effectiveness is yet untested. Hazing, lure crops …

Go to article

First Cohort Of Migratory Whooping Cranes Reintroduced To Eastern North America: The First Year After Release, Richard P. Urbanek, Lara E. A. Fondow, Colleen D. Satyshur, Anne E. Lacy, Sara E. Zimorski, Marianne Wellington Jan 2005

First Cohort Of Migratory Whooping Cranes Reintroduced To Eastern North America: The First Year After Release, Richard P. Urbanek, Lara E. A. Fondow, Colleen D. Satyshur, Anne E. Lacy, Sara E. Zimorski, Marianne Wellington

Proceedings of the North American Crane Workshop

We describe the post-release movements and survival of the first cohort in the eastern migratory whooping crane (Grus americana) reintroduction from release the first winter through return the second winter. Six cranes were led behind ultralight aircraft from Necedah National Wildlife Refuge (NWR), Central Wisconsin, to Chassahowitzka NWR, Gulf Coast of Florida. After release in Florida, 1 of these cranes and another transported there by truck were killed by bobcats (Lynx rufus). The winter management protocol was modified and no further predation occurred. The 5 remaining cranes migrated unassisted back to Necedah NWR in spring, left …

Go to article

Sandhill Crane Mortality During Fall Migration Stopover In North-Central New Mexico, Fall 2001, William Deragon, Wendy Brown, Gail Garber, Mike Richard Jan 2005

Sandhill Crane Mortality During Fall Migration Stopover In North-Central New Mexico, Fall 2001, William Deragon, Wendy Brown, Gail Garber, Mike Richard

Proceedings of the North American Crane Workshop

Seventy-three Rocky Mountain greater sandhill cranes died after being mired in mud at a traditional migration stopover site during a fall migration 2001. Drawdown of the Jemez Canyon Dam reservoir in New Mexico resulted in over 200 acres of deep saturated silt and clay into which sandhill cranes became entrapped. Harassment to discourage birds from landing in the area was implemented immediately and partially successful. Rescue efforts were delayed because of an inability to safely access the cranes in these conditions. After 9 days, the use of a specialized 20-horsepower motor mounted on a small aluminum boat was employed. Seventeen …

Go to article

Impact Of Management Changes At An Autumn Greater Sandhill Crane Staging Area In Oregon, Carrol D. Littlefield Jan 2005

Impact Of Management Changes At An Autumn Greater Sandhill Crane Staging Area In Oregon, Carrol D. Littlefield

Proceedings of the North American Crane Workshop

Malheur National Wildlife Refuge, Oregon was the most important autumn staging area for greater sandhill cranes (Grus canadensis tabida) in the northwest Pacific coastal states. During 1983-88, changes in management including increases in human disturbance and habitat alterations resulted in significant declines in autumn crane use. Compared with the period 1975-82, mean annual autumn crane peak numbers declined from 2,454 to 1,352, whereas mean biweekly numbers declined from 791 to 353. Management changes included roost site drying and flooding of a primary feeding area; disturbance factors included cattle herding through a loafing site and dump trucks traveling through …

Go to article

A Fresh Look At The Taxonomy Of Midcontinental Sandhill Cranes, Douglas H. Johnson, Jane E. Autin, Jill A. Shaffer Jan 2005

A Fresh Look At The Taxonomy Of Midcontinental Sandhill Cranes, Douglas H. Johnson, Jane E. Autin, Jill A. Shaffer

Proceedings of the North American Crane Workshop

The midcontinental population of sandhill crane (Grus canadensis) includes about 500,000 birds and provides valuable recreational crane-watching and hunting opportunities in Canada and the United States. It comprises three subspecies, one of which (G. c. rowani) was of uncertain taxonomic status and another of which (G. c. tabida) merited protection from excessive harvest due to its small population size. We obtained measurements of cranes used by Johnson and Stewart (1973) and additional crane specimens to 1) evaluate the subspecies designation of midcontinental sandhill cranes and 2) to seek improved methods for classifying cranes from …

Go to article

Breeding Biology Of Re-Introduced Non-Migratory Whooping Cranes In Florida, Martin J. Folk, Stephen A. Nesbitt, Stephen T. Schwikert, James A. Schmidt, Kathleen A. Sullivan, Thomas J. Miller, Stephen B. Baynes, Jeannette M. Parker Jan 2005

Breeding Biology Of Re-Introduced Non-Migratory Whooping Cranes In Florida, Martin J. Folk, Stephen A. Nesbitt, Stephen T. Schwikert, James A. Schmidt, Kathleen A. Sullivan, Thomas J. Miller, Stephen B. Baynes, Jeannette M. Parker

Proceedings of the North American Crane Workshop

In the face of record-setting drought, the re-introduced flock of non-migratory whooping cranes in Florida has shown slow but steady progress toward achieving the first natural recruitment to the flock. Fourteen nests were initiated between 1999 and 2002. Two clutches have hatched a total of 4 chicks and 1 chick was raised to fledging. Captive-raised, soft-released whooping cranes have shown that they are capable of forming pair bonds, defending territories, building nests, laying fertile eggs, and hatching and rearing young. The key to the success of the project will be to have enough pairs producing enough young to offset annual …

Go to article

Resolutions Passed By The North American Crane Working Group Jan 2005

Resolutions Passed By The North American Crane Working Group

Proceedings of the North American Crane Workshop

FRESHWATER INFLOWS FOR CONSERVATION OF BLUE CRABS AND WHOOPING CRANES Research has shown that whooping cranes require abundant blue crab populations on which to forage to meet their energy needs. The NACWG urges the Texas Council of Environmental Quality to grant a water right to the San Marcos River Foundation at the maximum level requested (1.15 million acre-feet) to provide freshwater inflows for conservation purposes as identified in a study conducted by the Texas Parks and Wildlife Department. These inflows would increase blue crab populations, keep the bays and marshes productive in whooping crane critical habitat at Aransas, and help …

Go to article

First Prev Next Last