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

Population Biology Commons

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

Series

2008

Discipline
Institution
Keyword
Publication

Articles 1 - 30 of 80

Full-Text Articles in Population Biology

Geographic Variation In Malarial Parasite Lineages In The Common Yellowthroat (Geothlypis Trichas), K. M. Pagenkopp, John Klicka, K. L. Durrant, J. C. Garvin, R. C. Fleischer Dec 2008

Geographic Variation In Malarial Parasite Lineages In The Common Yellowthroat (Geothlypis Trichas), K. M. Pagenkopp, John Klicka, K. L. Durrant, J. C. Garvin, R. C. Fleischer

Ornithology Program (HRC)

Our current understanding of migration routes of many birds is limited and researchers have employed various methods to determine migratory patterns. Recently, parasites have been used to track migratory birds. The objective of this study was to determine whether haemosporidian parasite lineages detect significant geographic structure in common yellowthroats (Geothlypis trichas). We examined liver tissue or blood from 552 birds sampled from multiple locations throughout the continental United States, southern Canada, and the Bahamas. We found a 52.7% overall prevalence of haematozoan infection. We identified 86.1% of these infections to genus: 81% were Plasmodium; 5% were Haemoproteus …


Effects Of Olfactory And Visual Predators On Nest Success And Nest-Site Selection Of Waterfowl In North Dakota, Jennifer Borgo Dec 2008

Effects Of Olfactory And Visual Predators On Nest Success And Nest-Site Selection Of Waterfowl In North Dakota, Jennifer Borgo

Green Canyon Environmental Research Area, Logan Utah

No abstract provided.


Unintended Facilitation Between Marine Consumers Generates Enhanced Mortality For Their Shared Prey, F. Joel Fodrie, Matthew D. Kenworthy, Sean P. Powers Dec 2008

Unintended Facilitation Between Marine Consumers Generates Enhanced Mortality For Their Shared Prey, F. Joel Fodrie, Matthew D. Kenworthy, Sean P. Powers

University Faculty and Staff Publications

We manipulated predator densities and prey vulnerability to explore how interactions between two predators affect overall mortality of their shared prey. Our threemember study system included eastern oysters (Crassostrea virginica) and two of its major consumers: southern oyster drills (Stramonita haemastoma) and stone crabs (Menippe adina). Field experiments demonstrated that drills and crabs foraging together generated higher than expected oyster mortality based on each species operating independently, even though crabs also killed some drills. In subsequent laboratory trials, we experimentally mimicked the handling of oysters by foraging crabs and confirmed that crabs facilitated drills by breeching oyster valves, thereby granting …


Spots Of Adult Male Red-Spotted Newts Are Redder And Brighter Than In Females: Evidence For A Role In Mate Selection?, Andrew K. Davis, Kristine L. Grayson Nov 2008

Spots Of Adult Male Red-Spotted Newts Are Redder And Brighter Than In Females: Evidence For A Role In Mate Selection?, Andrew K. Davis, Kristine L. Grayson

Biology Faculty Publications

As aquatic adults, eastern red-spotted newts (Notophthalmus v. viridescens) are generally green with two rows of dorsal spots, which vary in number between individuals and range in colour from orange to red. The function of these spots is unknown, but it is possible that they serve as sexual ornamentations and we examined this hypothesis by testing for sexual dimorphism in spot characteristics. We used an image analysis approach that has been used previously with this and other amphibian species to compare the number, size and colour – redness (hue score) and brightness – of spots in 100 male …


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, …


Habitat-Mediated Foraging Limitations Drive Survival Bottlenecks For Juvenile Salmon, Brian P. Kennedy, Keith H. Nislow, Carol L. Folt Sep 2008

Habitat-Mediated Foraging Limitations Drive Survival Bottlenecks For Juvenile Salmon, Brian P. Kennedy, Keith H. Nislow, Carol L. Folt

Dartmouth Scholarship

Realistic population models and effective conservation strategies require a thorough understanding of mechanisms driving stage-specific mortality. Mortality bottlenecks for many species occur in the juvenile stage and are thought to result from limitation on food or foraging habitat during a "critical period" for growth and survival. Without a way to account for maternal effects or to measure integrated consumption rates in the field, it has been virtually impossible to test these relationships directly. Hence uncertainties about mechanisms underlying such bottlenecks remain. In this study we randomize maternal effects across sites and apply a new method for measuring consumption integrated over …


Drift By Drift: Effective Population Size Is Limited By Advection, John P. Wares, James M. Pringle Aug 2008

Drift By Drift: Effective Population Size Is Limited By Advection, John P. Wares, James M. Pringle

Earth Sciences

Background: Genetic estimates of effective population size often generate surprising results, including dramatically low ratios of effective population size to census size. This is particularly true for many marine species, and this effect has been associated with hypotheses of "sweepstakes" reproduction and selective hitchhiking. Results: Here we show that in advective environments such as oceans and rivers, the mean asymmetric transport of passively dispersed reproductive propagules will act to limit the effective population size in species with a drifting developmental stage. As advection increases, effective population size becomes decoupled from census size as the persistence of novel genetic lineages is …


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 …


A New Reproductive Mode In The Genus Melanzophryniscus Gallardo, 1961 (Anura: Bufonidae) With Description Of A New Species From The State Of Paraná, Brazil, José A. Langone, Magno V. Segallo, Marcos Bornschein, Rafael O. De Sá Apr 2008

A New Reproductive Mode In The Genus Melanzophryniscus Gallardo, 1961 (Anura: Bufonidae) With Description Of A New Species From The State Of Paraná, Brazil, José A. Langone, Magno V. Segallo, Marcos Bornschein, Rafael O. De Sá

Biology Faculty Publications

A new species of bufonid toad of the genus Melanophryniscus is described from a mountaintop that is part of the Serra do Mar in the northeastern State of Paraná, Brazil. Melanophryniscus alipioi sp. nov. is distinguished from other known species by its uniformly dark brown dorsal color and a unique breeding site. The new species reproduces in bromeliads, a reproductive mode previously unknown for this genus. This species might be susceptible to current habitat lost.


The Horseshoe Crab Conundrum: Can We Harvest And Conserve?, Jennifer Mattei, Mark Beekey Apr 2008

The Horseshoe Crab Conundrum: Can We Harvest And Conserve?, Jennifer Mattei, Mark Beekey

Biology Faculty Publications

Horeshoe crabs "Limulus polyphemus" are remarkable ‘living fossils’ which have unique blood cells (amebocytes) that are used to test human vaccines for bacterial contamination. In the 1950’s, scientists at the Marine Biological Laboratory in Woods Hole, Massachusetts, not only discovered amebocytes but also found that they had special properties. If the amebocytes came into contact with bacteria, they would instantly coagulate around the bacteria and attack it. The Woods Hole scientists took this unique property of horseshoe crabs and developed a test for bacterial contamination using a horseshoe crab blood derivative called Limulus Amebocyte Lysate (LAL).

This article describes discusses …


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 …


Historic Genetic Structuring And Paraphyly Within The Great-Tailed Grackle, Jeffrey M. Dacosta, Walter Wehtje, John Klicka Feb 2008

Historic Genetic Structuring And Paraphyly Within The Great-Tailed Grackle, Jeffrey M. Dacosta, Walter Wehtje, John Klicka

Ornithology Program (HRC)

The Great-tailed Grackle (Quiscalus mexicanus) and Boat-tailed Grackle (Q. major) are sister species that have expanded their ranges during historical times. This expansion has created an area of sympatry between these species in Texas and Louisiana, and between distinctive Great-tailed Grackle subspecies in the southwestern United States and northern Mexico. We investigated the evolutionary histories of both species using mitochondrial DNA sequence data and modern phylogenetic methods. Our results reveal genetic structure within Great-tailed, but not Boat-tailed Grackles. Great-tailed Grackles are separated into two clades, but range expansion in the north has led to secondary contact …


Collaborative Research: Extreme Discordance Between Allozyme And Non-Allozyme Introgression In Baltic Mussels. Selection On Allozymes?, Paul D. Rawson Jan 2008

Collaborative Research: Extreme Discordance Between Allozyme And Non-Allozyme Introgression In Baltic Mussels. Selection On Allozymes?, Paul D. Rawson

University of Maine Office of Research Administration: Grant Reports

A major challenge for evolutionary biologists is to determine the degree to which natural selection shapes genetic variation in natural populations. Hybridization is common between two species of blue mussel found in the North and Baltic Seas. The differential exchange of genes between the two mussel species, particularly genes encoding enzymes involved in central metabolic pathways, suggests those genes may be under selection and involved in adaptation to low salinity conditions in the Baltic Sea. Tests for selection will be conducted by comparing levels of genetic exchange for these metabolic genes against nonmetabolic and presumably neutral (i.e., not under selection) …


A Sex Difference In Seasonal Timing Of Birth In A Livebearing Fish, Eric T. Schultz Jan 2008

A Sex Difference In Seasonal Timing Of Birth In A Livebearing Fish, Eric T. Schultz

EEB Articles

Sex differences in seasonal timing include differences in hatch- or birth-date distribution and differences in the timing of migration or maturation such as protandrous arrival timing (PAT), which is early male arrival at breeding sites. I describe a novel form of protandrous arrival timing, as a sex difference in birth-date distribution in a live-bearing fish (Dwarf Perch, Micrometrus minimus). In this species, birth coincides with arrival at breeding sites because newborn males are sexually active. A series of samples of pregnant females and young of year was collected in Tomales Bay, CA. I analyzed the daily age record in otoliths …


A Watershed Analysis Of Pattee Pond: Implications For Water Quality And Land Use Management, Problems In Environmental Science Course (Biology 493), Colby College, Colby Environmental Assessment Team, Colby College Jan 2008

A Watershed Analysis Of Pattee Pond: Implications For Water Quality And Land Use Management, Problems In Environmental Science Course (Biology 493), Colby College, Colby Environmental Assessment Team, Colby College

Colby College Watershed Study: Pattee Pond (2008, 1992)

The Colby Environmental Assessment Team (CEAT) investigated the impact of land use patterns on the water quality of Pattee Pond in Winslow, Maine, during the summer and fall of 2008. Physical, chemical, and biological characteristics of water quality were analyzed to evaluate the current health of the lake. Data collected were compared with previous studies conducted by the Maine Department of Environmental Protection (DEP) and CEAT to examine changes in water quality and land use over time. Trends in Pattee Pond water quality suggest an improvement since the 1970s. However, the lake is still experiencing algal blooms resulting from phosphorus …


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 …