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Articles 541 - 570 of 703

Full-Text Articles in Population Biology

Egg Collection And Recruitment Of Young Of The Year In The Aransas/Wood Buffalo Population Of Whooping Cranes, John R. Cannon, Brian W. Johns, Thomas V. Stehn Jan 2001

Egg Collection And Recruitment Of Young Of The Year In The Aransas/Wood Buffalo Population Of Whooping Cranes, John R. Cannon, Brian W. Johns, Thomas V. Stehn

Proceedings of the North American Crane Workshop

We present data for 61 years (1938 to 1998) on the recruitment of juvenile (i.e., young-of-the-year) whooping cranes (Grus americana) for the 1 natural wild population that nests in the vicinity of Wood Buffalo National Park (WBNP) in Canada and migrates annually to wintering grounds in the vicinity of Aransas National Wildlife Refuge (ANWR) on the Gulf coast of Texas in the United States. We divide these years into 2 data sets: years during which 1 of 2 eggs was collected from WBNP nests (to develop captive populations and to conduct reintroduction experiments), and years during which no …

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Status Of Sandhill Cranes In Indiana, John S. Castrale, James Bergens Jan 2001

Status Of Sandhill Cranes In Indiana, John S. Castrale, James Bergens

Proceedings of the North American Crane Workshop

Historically, the sandhill crane (Grus canadensis) was considered a common migrant throughout Indiana and a locally abundant breeding bird in northwestern Indiana until 1929. Most of the Eastern Population of greater sandhill cranes (G. c. tabida) is thought to congregate each fall at Jasper-Pulaski Fish and Wildlife Area before migrating to Florida and Georgia. Systematic weekly fall counts began in 1967 and annual peak numbers have increased from 2,500 in 1967 to 27,600 in 1997, with a record count of 32,600 in 1991. Fall migrants are noticeable by late September, peak in mid-October through mid-November, and …

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Tracking Sandhill Crane Migration From Saskatchewan To The Gulf Coast, Dale G. Hjertaas, David H. Ellis, Brian W. Johns, Stacie L. Moon Jan 2001

Tracking Sandhill Crane Migration From Saskatchewan To The Gulf Coast, Dale G. Hjertaas, David H. Ellis, Brian W. Johns, Stacie L. Moon

Proceedings of the North American Crane Workshop

Four adult sandhill cranes (Grus canadensis rowani) were captured in east-central Saskatchewan, equipped with transmitters, and tracked by satellite to detennine if their migration routes and wintering areas would allow their use as guide birds to establish a new migratory flock of whooping cranes (G. americana). Two birds captured near Yorkton died or their transmitters were lost before migration. Two adults from the Overflowing River moved to staging areas in southern Saskatchewan in September. By 29 September, Crane A left Saskatchewan and moved to North Dakota where it remained until late October. By 21 December, it …

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Fate Of The Survivors Of The 1995 And 1996 Arizona Trucking Migrations Of Costume-Reared Greater Sandhill Cranes, Daniel P. Mummert, David H. Ellis, Carol L. Chambers Jan 2001

Fate Of The Survivors Of The 1995 And 1996 Arizona Trucking Migrations Of Costume-Reared Greater Sandhill Cranes, Daniel P. Mummert, David H. Ellis, Carol L. Chambers

Proceedings of the North American Crane Workshop

In 1995 and 1996, we trained 2 groups of costume-reared greater sandhill cranes (Grus canadensis tabida) (10 in 1995, 14 in 1996) to follow a truck. Thereafter we led 10 in 1995 and 12 in 1996 from Garland Prairie, northern Arizona, to the Buenos Aires National Wildlife Refuge, southern Arizona (ca. 620 km). These techniques were being developed to create additional, disjunct populations of the whooping crane (G. americana). The cranes taught the migration route in 1995 did not follow the desired migration route in 1996 but did travel north 140 km along the route in …

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Results Of The First Ultralight-Led Sandhill Crane Migration In Eastern North America, Joseph W. Duff, William A. Lishman, Dewitt A. Clark, George F. Gee, David H. Ellis Jan 2001

Results Of The First Ultralight-Led Sandhill Crane Migration In Eastern North America, Joseph W. Duff, William A. Lishman, Dewitt A. Clark, George F. Gee, David H. Ellis

Proceedings of the North American Crane Workshop

In 1997, we led 8 sandhill cranes (Grus canadensis) south from Ontario, Canada by ultralight aircraft to a wintering area near Warrenton, Virginia, an area without a wild population. Six others were transported south in a trailer in hopes they would return north with those that flew. The migration was 863 kIn long, included 14 stops, and took 21 days to complete. A1l13 SUIViving birds were wintered together. In March 1998, the surviving 7 "aircraft-led" birds departed the wintering site. The following day, 6 of the 7 were reported on the south shore of Lake Ontario. The flock …

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Food Items And Feeding Rates For Wild Whooping Crane Colts In Wood Buffalo National Park, Douglas G. Bergeson, Mark Bradley, Geoffrey L. Holroyd Jan 2001

Food Items And Feeding Rates For Wild Whooping Crane Colts In Wood Buffalo National Park, Douglas G. Bergeson, Mark Bradley, Geoffrey L. Holroyd

Proceedings of the North American Crane Workshop

Food habits of 5 whooping crane (Orus americana) colts in 4 nest ponds were recorded in the days following hatching in Wood Buffalo National Park (WBNP). In total, 93 hours of observations were made from blinds that were 60-80 m away from the nest. Spotting scopes and binoculars were used to identify food items. The adults were observed bringing the following items to the colts: adult dragonflies (Libellula sp., and Aeshna sp.), fish (Culaea inconstans), diving beetles (Rhantus binotatus, Acilius semisulcatus, Oraphoderus occidentalis, and Dytiscus alaskanus), damselflies (Enallagma sp., and Lestes sp.), …

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Sandhill Crane Abundance At Grays Lake, Idaho, L J. Ball, Jane E. Austin, Adonia R. Henry Jan 2001

Sandhill Crane Abundance At Grays Lake, Idaho, L J. Ball, Jane E. Austin, Adonia R. Henry

Proceedings of the North American Crane Workshop

We initiated a study on the breeding ecology of greater sandhill cranes (Grus canadensis tabida) in the Grays Lake basin ofIdaho in 1997. Interest in the status of crane populations at Grays Lake is high; consequently, we present preliminary information on estimated size of the population, changes since the 1970s, and potential environmental factors involved. Drewien (1973) counted an average of549 cranes in the spring and estimated 250 nesting pairs in 1970-71. Number of nesting pairs reportedly increased 33% (to 332) by 1982 in response to intensive management, then declined 40-60% by 1996 (Drewien 1997, and Homocker Wildlife …

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Nesting Ecology Of Sandhill Cranes At Grays Lake, Idaho, Jane E. Austin, L. J. Ball, Adonia R. Henry Jan 2001

Nesting Ecology Of Sandhill Cranes At Grays Lake, Idaho, Jane E. Austin, L. J. Ball, Adonia R. Henry

Proceedings of the North American Crane Workshop

We examined the nesting ecology of greater sandhill cranes (Grus canadensis tabida) at Grays Lake, Idaho during 1997-99 to detennine the effects of nest-site characteristics and land use on crane nest success. These are preliminary results from 3 years of a 4-year study. Crane nests were located in portions of the Grays Lake basin from early May through late June each year (n = 131 in 1997; n = 131 in 1998; n = 143 in 1999). Apparent nest success varied among years (54% in 1997, 71% in 1998, and 53% in 1999; overall average of 59%). We …

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Translocation Of Florida Sandhill Cranes To Georgia, Wesley A. Abler, Stephen A. Nesbitt Jan 2001

Translocation Of Florida Sandhill Cranes To Georgia, Wesley A. Abler, Stephen A. Nesbitt

Proceedings of the North American Crane Workshop

Wild Florida sandhill cranes (Grus canadensis pratensis) were captured in Florida during 3 years and translocated to Grand Bay Wildlife Management Area (GBWMA), Georgia, in an attempt to establish a resident population of Florida sandhill cranes in a location with suitable habitat but no known population of resident sandhill cranes. Translocated second-year subadult cranes commingled with migratory greater sandhill cranes (G. c. tabida) yet remained on GBWMA each year after the migratory birds left the area. Twenty-one of 35 released cranes were visually identified at least 5 months after release, 3 cranes more than 15 months …

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Results Of The Second (1996) Experiment To Lead Cranes On Migration Behind A Motorized Ground Vehicle, David H. Ellis, Brian Clauss, Tsuyoshi Watanabe, R. Curt Mykut, Matt Shawkey, Daniel P. Mummert, Daniel T. Sprague, Catherine H. Ellis, F. Benjamin Trahan Jan 2001

Results Of The Second (1996) Experiment To Lead Cranes On Migration Behind A Motorized Ground Vehicle, David H. Ellis, Brian Clauss, Tsuyoshi Watanabe, R. Curt Mykut, Matt Shawkey, Daniel P. Mummert, Daniel T. Sprague, Catherine H. Ellis, F. Benjamin Trahan

Proceedings of the North American Crane Workshop

Fourteen greater sandhill cranes (Grus canadensis tabida) were trained to follow a specially-equipped truck and 12 were led along a ca 620-Ian route from Camp Navajo in northern Arizona to the Buenos Aires National Wildlife Refuge near the ArizonalMexico border. Ten survived the trek, 380 Ian of which were flown, although only a few cranes flew every stage of the route. Major problems during the migration were powerline collisions (ca 15, 2 fatal) and overheating (when air temperatures exceeded ca 25° C). The tenacity of the cranes in following both in 1995 and 1996 under unfavorable conditions (e.g., …

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Recommendations For The Attachment Of Satellite Transmitters To Cranes, David H. Ellis, Paul W. Howey, Gary L. Krapu Jan 2001

Recommendations For The Attachment Of Satellite Transmitters To Cranes, David H. Ellis, Paul W. Howey, Gary L. Krapu

Proceedings of the North American Crane Workshop

Recent advances in miniaturization of satellite transmitters have resulted in thumb-sized packages weighing less than 30 g. These are smaller than VHF radios routinely mounted on crane leg bands. With this development and with favorable signal reception results, there is no need for, and much to recommend against, the continued use of back-pack mounts. We provide details for leg-mount attachments.

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Resolutions Passed By The North American Crane Working Group Eighth North American Crane Workshop, Albuquerque, New Mexico U.S.A. Jan 2001

Resolutions Passed By The North American Crane Working Group Eighth North American Crane Workshop, Albuquerque, New Mexico U.S.A.

Proceedings of the North American Crane Workshop

Participants of the Eighth North American Crane Workshop hereby express their thanks and appreciation to the Bosque del Apache National Wildlife Refuge for hosting this workshop, to the staff of the Sheraton Old Town Hotel, to the field trip leaders, to the staff of the Bernardo Waterfowl Management Area, and to the committees and individuals who made the workshop a success. The paper sessions were excellent, and the spirit of friendship and dedication to crane conservation among the participants was revitalizing. Special thanks go to NACWG President Scott Hereford and Bosque del Apache Biologist John Taylor for their tireless effort …

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Population Genetics Of Midcontinent Sandhill Cranes, Jessica L. Petersen, Richard Bischof, Allen L. Szalanski Jan 2001

Population Genetics Of Midcontinent Sandhill Cranes, Jessica L. Petersen, Richard Bischof, Allen L. Szalanski

Proceedings of the North American Crane Workshop

The Midcontinent Sandhill Crane Population is comprised of 3 subspecies, lesser (Grus canadensis canadensis), Canadian (G. c. rowani), and greater (G. c. tabida) sandhill cranes. In conjunction with the USGS Northern Prairie Wildlife Research Center, we studied the extent of genetic variation between and within each race of the Midcontinent Sandhill Crane Population. DNA was extracted from 150 feather and dried blood samples collected from 1995-99 from sandhill cranes in the Platte River Valley, central Nebraska. Parsimony and maximwn likelihood analysis of the mtDNA D-loop sequences (ca 675 bp amplified using PCR) from 29 …

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Aspects Of Reproduction And Pair Bonds In Florida Sandhill Cranes, Stephen A. Nesbitt, Martin J. Folk, Stephen T. Schwikert, James A. Schmidt Jan 2001

Aspects Of Reproduction And Pair Bonds In Florida Sandhill Cranes, Stephen A. Nesbitt, Martin J. Folk, Stephen T. Schwikert, James A. Schmidt

Proceedings of the North American Crane Workshop

From 1980-98 we captured and uniquely marked more than 400 Florida sandhill cranes (Grus canadensis prafensis). Age ratios of the marked population, excluding juveniles, was 66% adult and 33% subadult, and the sex ratio was 49% male and 51% female. Average clutch size for 210 nests checked from 1983-97 was 1.78 ± 0.18 (SD) and frequency of l-egg clutches varied among years. Average post-fledging brood size from 1991 to 1997 was 1.27 ± 0.17 (SD), included a 3-chick brood. Average percent ofYOlmg from 2 study areas, 1991-97 was 11.9 ± 3.23 (SD). We observed renesting up to 3 …

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An Update Of The Florida Whooping Crane Release Project Through June 2000, Stephen A. Nesbitt, Martin J. Folk, Kathleen A. Sullivan, Stephen T. Schwikert, Marilyn G. Spalding Jan 2001

An Update Of The Florida Whooping Crane Release Project Through June 2000, Stephen A. Nesbitt, Martin J. Folk, Kathleen A. Sullivan, Stephen T. Schwikert, Marilyn G. Spalding

Proceedings of the North American Crane Workshop

Whooping cranes (Grus americana) reared mostly at the USGS Patuxent Wildlife Research Center (patuxent) or the International Crane Foundation (ICF) have been released in Florida in an effort to reestablish a nonmigratory population in the southeastern United States. From 1993 through spring of 2000, we released 208 cranes. Modifications to the release procedure instituted in 1995 have greatly reduced mortality from the initial release period. First year mortality has averaged 50%. A longterm drought that began after spring 1998 may have contnbuted to increased first year mortality in recent years. Most mortality has been from predation, mostly bobcat …

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A Comparison Of Behavior For Two Cohorts Of Captive-Reared Greater Sandhill Cranes Released In Northern Arizona, Daniel P. Mummert, Carol L. Chambers, David H. Ellis Jan 2001

A Comparison Of Behavior For Two Cohorts Of Captive-Reared Greater Sandhill Cranes Released In Northern Arizona, Daniel P. Mummert, Carol L. Chambers, David H. Ellis

Proceedings of the North American Crane Workshop

To determine how the behavior of greater sandhill cranes (Grus canadensis tabida) changes according to time of year, time of day, and number of days after release, we observed the activities of 2 groups of captive-reared greater sandhill cranes at Mormon Lake, northern Arizona. The behaviors we compared were alert, loafing, sleeping, foraging, preening, locomotion, and other. We found costume-reared subadult greater sandhill cranes that were established at the study site for a year spent more time foraging and being alert towards predators than parent -reared juvenile greater sandhill cranes that were recently released from captivity. We also …

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Sandhill Crane Nest And Egg Characteristics At Malheur National Wildlife Refuge, Oregon, Carroll D. Littlefield Jan 2001

Sandhill Crane Nest And Egg Characteristics At Malheur National Wildlife Refuge, Oregon, Carroll D. Littlefield

Proceedings of the North American Crane Workshop

For the period 1969-89, greater sandhill crane (Grus canadensis tabida) nest and egg characteristics were assessed for pairs on the Malheur National Wildlife Refuge (Malheur), Oregon. Nests mostly were in broad-fruited burreed (Sparganium eurycarpum) and hardstem bulrush (Scirpus acutus) and were constructed primarily of the same vegetative species that surrounded nests. Averages for nest parameters were diameter 127 xIII cm, crown diameter 77 x 69 cm, bowl diameter 41 x 37 em, bowl depth 5.8 em, nest height 12.4 em, and water depth 25.8 cm. Nests were placed in vegetation with a mean height …

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Effects Of An Early Spring Burn On Greater Sandhill Crane Nesting Success At Malheur National Wildlife Refuge, Oregon, Carroll D. Littlefield, John E. Cornely, Bradley D. Ehlers Jan 2001

Effects Of An Early Spring Burn On Greater Sandhill Crane Nesting Success At Malheur National Wildlife Refuge, Oregon, Carroll D. Littlefield, John E. Cornely, Bradley D. Ehlers

Proceedings of the North American Crane Workshop

A 2430 ha prescribed burn was conducted on Malheur National Wildlife Refuge, Harney County, Oregon in March 1985. About 35 days later, 11 greater sandhill crane (Grus canadensis tabida) pairs nested within the burned area; 9 of these hatched. The remaining 2 clutches were destroyed by coyotes (Canis latrans). Crane hatching success was significantly higher (P = 0.01) on the burned area (81.8%) than elsewhere (38.5%). Two factors were likely responsible for the higher success rate in the burn; nests were placed in deeper water and the smaI1 mammal prey base was temporarily reduced or eliminated …

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Evaluation Of The Major Histocompatibility Complex (Mhc) In Cranes: Applications To Conservation Efforts, Susan I. Jarvi, Marcia M. Miller, Ronald M. Gotol, George F. Gee, W. Elwood Briles Jan 2001

Evaluation Of The Major Histocompatibility Complex (Mhc) In Cranes: Applications To Conservation Efforts, Susan I. Jarvi, Marcia M. Miller, Ronald M. Gotol, George F. Gee, W. Elwood Briles

Proceedings of the North American Crane Workshop

Although there have been heated discussions concerning the relative importance of using Mhc diversity as a basis for selecting breeders in conservation projects, most parties agree that the genetic variability residual in an endangered species should be maintained through genetic management, if at all possible. Substantial evidence exists (particularly in birds) documenting the influences of specific Mhc haplotypes on disease outcome and also that those individuals which are heterozygous for Mhc alleles appear to have an advantage for survival over those that are homozygous. Thus, conservation of genetic variability of the Mhc is likely important for the preservation of fitness, …

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Distribution, Abundance, And Reproduction Of The Cuban Sandhill Crane (Grus Canadensis Nesiotes), Xiomara Galvez Aguilera, Vicente Berovides Alvarez, Jose Rivera Rosales Jan 2001

Distribution, Abundance, And Reproduction Of The Cuban Sandhill Crane (Grus Canadensis Nesiotes), Xiomara Galvez Aguilera, Vicente Berovides Alvarez, Jose Rivera Rosales

Proceedings of the North American Crane Workshop

We discuss the distribution, abundance, and reproduction of the Cuban sandhill crane (Grus canadensis nesiotes). This is an overview of a 5-year study conducted by the National Organization for the Protection of Flora and Fauna of the Ministry of Agriculture for the Republic of Cuba and assisted by the International Crane Foundation and Brehm Fund. The distribution of this subspecies was determined by visiting potential sites and areas where this race has previously been reported. Nine new populations were found. This brings the total to 11 on the Isle of Cuba, 1 on Cayo Romano, and 2 on …

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Interactions Of Sandhill Cranes And Whooping Cranes With Foreign Objects In Florida, Martin J. Folk, Stephen A. Nesbitt, Marilyn G. Spalding Jan 2001

Interactions Of Sandhill Cranes And Whooping Cranes With Foreign Objects In Florida, Martin J. Folk, Stephen A. Nesbitt, Marilyn G. Spalding

Proceedings of the North American Crane Workshop

During studies of Florida sandhill cranes (Grus canadensis pralensis), greater sandhill cranes (G. c. tabida), and whooping cranes (G. americana) in Florida, we documented cases where these birds were in contact with human-produced objects that resulted in injury or death. We describe >40 instances in which cranes collided with powerlines or fences, became entangled in string or fishing line, or ingested foreign objects. The effect of human-produced objects on crane populations, particularly small populations, may be significant.

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New World Nine-Primaried Oscine Relationships: Constructing A Molecular Framework, John Klicka, Kevin P. Johnson, Scott M. Lanyon Apr 2000

New World Nine-Primaried Oscine Relationships: Constructing A Molecular Framework, John Klicka, Kevin P. Johnson, Scott M. Lanyon

Ornithology Program (HRC)

Historically, a paucity of comparative morphological characters has led to much debate regarding relationships within and among the major lineages of New World nine-primaried oscines. More recently, DNA-DNA hybridization studies have provided novel and testable hypotheses of relationships, although no consensus has been reached. For 40 songbird taxa, we obtained 1,929 base pairs (bp) of DNA sequence from the mitochondrial cytochrome-b (894 bp) and NADH dehydrogenase subunit 2 (1,035 bp) genes. Phylogenetic analyses confirm the monophyly of this assemblage as traditionally defined. The lineages delineated historically on morphological grounds are retained; finches (Fringillinae) are sister to a well-supported clade …

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Breeding Season Demography And Movements Of Eastern Towhees At The Savannah River Site, South Carolina, David G. Krementz, Larkin A. Powell Jan 2000

Breeding Season Demography And Movements Of Eastern Towhees At The Savannah River Site, South Carolina, David G. Krementz, Larkin A. Powell

School of Natural Resources: Faculty Publications

The Eastern Towhee (Pipilo erythrophthalmus) has undergone population declines across much of its range, especially in New England. Despite being a widespread and, at one time, a common species, relatively little is known about its natural history, ecology, or demographics. We conducted baseline research on Eastern Towhees at the Savannah River Site, South Carolina, in 1995 and 1996 to estimate breeding season survival rates, nest success rates, breeding densities, and daily movements. We also were interested in whether towhees had differences in survival and movement rates between young and mature managed pine stands. We found that survival rates during the …

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Habitat Selection, Reproductive Success, And Impaling Patterns Of A Migratory Population Of Loggerhead Shrikes, Jeffrey D. Esely Jr. Jan 1998

Habitat Selection, Reproductive Success, And Impaling Patterns Of A Migratory Population Of Loggerhead Shrikes, Jeffrey D. Esely Jr.

Masters Theses

I studied habitat selection and reproductive success of a migratory population of Loggerhead Shrikes (Lanius ludovicianus migrans) as well as the temporal and spatial patterns of impaling exhibited by this population during the nesting season. The selection of breeding habitat was investigated at different spatial scales. Thirty-eight (67%) of 57 nests were located in osage orange (Maclura pomifera) trees. Shrike territories (area ≤ 200 m from nest site) contained significantly more pasture, fenceline, and perch sites, but less com, alfalfa, and forest than random sites. At larger spatial scales, more grassland was detected within 300 m …

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Habitat Use By Migrant Whooping Cranes In Saskatchewan, Brian W. Johns, Eric J. Woodsworth, Ed A. Driver Jan 1997

Habitat Use By Migrant Whooping Cranes In Saskatchewan, Brian W. Johns, Eric J. Woodsworth, Ed A. Driver

Proceedings of the North American Crane Workshop

We investigated habitat use by migrating whooping cranes (Grus americana) in Saskatchewan between 1986 and 1990. At foraging and roosting sites and a sample of randomly selected sites we measured various habitat parameters. Palustrine and lacustrine wetlands were the most frequently used wetlands. Temporary and seasonal wetlands were the primary roost habitat during spring migration, and semi-permanent and permanent wetlands were frequently used during the fall. Cranes were attracted to areas of higher than average wetland density. Land use within 2 km of roost sites was intensively modified by man. Cereal crops were the most used feeding areas. …

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Availability Of Stopover Habitat For Migrant Whooping Cranes In Nebraska, Dale W. Stahlecker Jan 1997

Availability Of Stopover Habitat For Migrant Whooping Cranes In Nebraska, Dale W. Stahlecker

Proceedings of the North American Crane Workshop

Four stratified random samples of 512 National Wetland Inventory (NWI) maps within the central Nebraska portion of the Wood Buffalo-Aransas whooping crane (Grus americana) migration corridor were used to evaluate the availability of wetland roost sites. Wetlands were eliminated as potential roosts if visibility was obscured by vegetation or slope, if certain human activities occurred within 100-800 ro, or if water < 30 em deep was not available. Seasonal emergent wetlands, available as roosts primarily in spring, dominated all samples, particularly in the nortb. Sixty-five percent of all wetlands >0.04 ha passed map review and 52 % passed when ground-truthed. NWI map review was a good predictor of both suitability (63 % correct) and unsuitability (73 % correct). More than one-half of all open and emergent …

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Woody Vegetation Expansion And Continuing Declines In Open Channel Habitat On The Platte River In Nebraska, Paul J. Currier Jan 1997

Woody Vegetation Expansion And Continuing Declines In Open Channel Habitat On The Platte River In Nebraska, Paul J. Currier

Proceedings of the North American Crane Workshop

Aerial videography in 1988 and 1994 of the same selected segments of the Big Bend reach of the Platte River in central Nebraska was compared. During this 6-year period, channel area declined 4 to 41 % (median 26%). In river segments where the channel had already narrowed significantly and at sites where channel habitat is actively managed declines were less (17-18%). These substantial changes occurred during a time that included a relatively low flow period (1990-92). Flows during the summer gertttination and establishment period (mid-May through August) for cottonwood (Populus deltoides) and willow (Salix spp.), the …

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Home Range And Habitat Use By Isolation-Reared Sandhill Cranes, Wenrui Duan, Theodore A. Bookhouts, Richard P. Urbanek Jan 1997

Home Range And Habitat Use By Isolation-Reared Sandhill Cranes, Wenrui Duan, Theodore A. Bookhouts, Richard P. Urbanek

Proceedings of the North American Crane Workshop

We isolation-reared, placed radio transmitters on, and released 38 greater sandhill cranes (Grus canadensis tabida) on Seney National Wildlife Refuge (Seney) in 1988-90 to develop procedures for initiating new populations of cranes. Here we report on habitat selection by breeding birds with functional radio transmitters. Home ranges established by 6 cranes in 1992, when they were 2 to 4 years old, averaged 199±50.8 (SE) ha (harmonic mean method, 75 % utilization) and were of 2 types: feeding grounds separated from nesting habitat and feeding grounds adjacent to nesting habitat. Home ranges consisted of 36% emergent palustrine wetlands, 28% …

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Recent Advances In Scheduling Strategies And Practical Techniques In Crane Artificial Insemination, Scott R. Swengel, Monica L. Tuite Jan 1997

Recent Advances In Scheduling Strategies And Practical Techniques In Crane Artificial Insemination, Scott R. Swengel, Monica L. Tuite

Proceedings of the North American Crane Workshop

We analyzed fertility patterns of 339 eggs laid 1985-93 at the International Crane Foundation by cranes whose sole means of fertility was artificial insemination (AI). Ten of 15 crane species were studied. Fertility rates increased significantly (P < 0.05) with (I) higher sperm density, (2) greater sperm motility, and (3) 2 vs. 1 vs. 0 inseminations 4-7 days before oviposition. Semen sample size was inversely related to sperm density and had no strong relationship with egg fertility. Inseminations less than 2.5-3.0 days before an egg is laid are probably too late to contribute to fertilizing the egg but may contribute substantially to fertilizing the next egg. We also describe practical knowledge gained during the past 10 years that apply to certain species or situations. Wattled cranes (Bugeranus carunculatus) have a long fertile period post-AI (up to 16 days), but may require more careful methods and special AI scheduling strategies. We also describe techniques for AI just after oviposition that are especially beneficial for Siberian cranes (Grus leucogeranus), and methods for maximizing sample delivery to the female.

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Sandhill Crane Hunts In The Rio Grande Valley And Southwest New Mexico, C. Gregory Schmitt, Barry Hale Jan 1997

Sandhill Crane Hunts In The Rio Grande Valley And Southwest New Mexico, C. Gregory Schmitt, Barry Hale

Proceedings of the North American Crane Workshop

Annual limited permit hunting seasons for sandhill cranes (Grus canadensis) were initiated in southwestern New Mexico (SWNM) in 1982 and in the middle Rio Grande Valley (MRGV) in 1986. Within the MRGV and SWNM are wintering areas for 3 migratory subspecies, including the lesser sandhill crane (G. c. canadensis) (lessers). Canadian sandhill crane (G. c. rowani) (Canadians), and greater sandhill crane (G. c. tabida) (greaters). We summarized annual season dates, bag limits, requirements for permits, procedures for examination of crane specimens at check stations, number of hunters, estimated harvest, mean harvest per …

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