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Articles 2011 - 2040 of 2249

Full-Text Articles in Animal Sciences

Sandhill Crane Collisions With Power Lines In Southcentral Nebraska, John P. Ward, Stanley H. Anderson Jan 1992

Sandhill Crane Collisions With Power Lines In Southcentral Nebraska, John P. Ward, Stanley H. Anderson

Proceedings of the North American Crane Workshop

Sandhill crane (Grus canadensis) collisions with power lines were studied in southcentral Nebraska in 1986 and 1987. Approximately 596 km of power lines were surveyed for dead cranes in 1986, and 210 km of power lines in 1987. A total of 135 dead cranes were located. Cranes collided 4 times more with transmission lines than distribution lines, although distribution lines were twice as abundant. We believe cranes collided with the static wires on the transmission lines. Juveniles and Canadian sandhill cranes (G.c. rowani) had a higher probability of colliding with power lines than other age groups …

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Observations Of Two Whooping Cranes Wintering In Brazoria County, Texas, Michael L. Lange Jan 1992

Observations Of Two Whooping Cranes Wintering In Brazoria County, Texas, Michael L. Lange

Proceedings of the North American Crane Workshop

Two sub-adult whooping cranes (Grus americana) wintered in the coastal marsh and grain fields of Brazoria County, Texas, during the winter of 1985-86. Observations were made on 59 days during the 75 day period the cranes were present. During December and January the whooping cranes primarily fed in waste corn fields. During February and March they fed primarily in brakish marshes. The whooping cranes flew over a tall electric transmission line a minimum of 80 times during the winter. To prevent the two whooping cranes from eating seed corn treated with pesticides it was necessary to haze the …

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Releasing Puppet-Reared Sandhill Cranes Into The Wild: A Progress Report, Kyoko Archibald, George Archibald Jan 1992

Releasing Puppet-Reared Sandhill Cranes Into The Wild: A Progress Report, Kyoko Archibald, George Archibald

Proceedings of the North American Crane Workshop

In 1982, 2 eggs from an abandoned greater sandhill crane (Grus canadensis tabida) nest were artificially incubated and hatched. Chicks were hand reared in partial visual isolation from humans with the aid of puppet heads. At 4-5 weeks of age, the chicks were placed in a fenced compound in a marsh frequented by their parents. During daylight hours the chicks were continually monitored by an observer in a blind. Until fully feathered, they were returned at night to an indoor shelter. Upon fledging, the chicks were released daily in the field where their parents foraged. The adults and …

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Social Preference Of Four Cross-Foster Reared Sandhill Cranes, Thomas A. Mahan, Brenda S. Simmers Jan 1992

Social Preference Of Four Cross-Foster Reared Sandhill Cranes, Thomas A. Mahan, Brenda S. Simmers

Proceedings of the North American Crane Workshop

Four greater sandhill cranes (Grus canadensis tabida) were hatched and reared individually by 4 non-sandhill crane pairs: 2 by white-naped crane (G. vipio) pairs, 1 by a Siberian crane (G. leucogeranus) pair, and 1 by a red-crowned crane (G. japonensis) pair. After 1 year the sandhill cranes (2 male and 2 female) were placed in enclosed pens adjacent to an oppositesexed, same-age bird of the foster species on 1 side and an opposite-sexed, same-age conspecific on the other side. Data were collected throughout 1 year and included proximity between test and choice …

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Sandhill Crane Habitat Use In Northeastern Utah And Southwestern Wyoming, Donald E. Mcivor, Michael R. Conover Jan 1992

Sandhill Crane Habitat Use In Northeastern Utah And Southwestern Wyoming, Donald E. Mcivor, Michael R. Conover

Proceedings of the North American Crane Workshop

Patterns of habitat use by greater sandhill cranes (Grus canadensis tabida) were examined during April-July 1991 when crop damage attributed to cranes normally occurs. We conducted surveys weekJy along 37-km transects in Cache Valley, Utah, and bi-weekly in the Bear River Valley in Rich County, Utah, and Lincoln County. Wyoming. During the surveys, we sighted 1,235 cranes in 165 separate groups in pasture (55%), small grains (19%), riparian (8%), alfalfa (6%), corn (3%), and miscellaneous (9%) habitats. Cranes did not use habitats in proportion to their availability (P < 0.0005); they fed more in small grain fields and pasture-hay habitats. Depredations attributed to cranes have been reported in Cache Valley corn crops in spring and in Bear River Valley small grain crops in fall. Farmers with chronic depredation problems in small grains and corn may wish to cultivate crops less preferred by cranes.

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Marking Power Lines To Reduce Avian Collision Mortality In The San Luis Valley, Colorado, Wendy M. Brown, Roderick C. Drewien Jan 1992

Marking Power Lines To Reduce Avian Collision Mortality In The San Luis Valley, Colorado, Wendy M. Brown, Roderick C. Drewien

Proceedings of the North American Crane Workshop

We examined the effectiveness of 2 marking devices designed to increase visibility of power lines and reduce avian collision mortality during spring and fall migration periods, 1988-91, in the San Luis Valley, Colorado. Eight O.8-km segments of power line were marked with either yellow spiral vibration dampers or yellow fiberglass swinging plates and compared with 8 adjoining unmarked segments. Primary species groups studied included cranes (Grus canadensis and G. americana), Canada geese (Branta canadensis), and ducks (various Anatinae). Raptors, shorebirds, wading birds, and passerines were also monitored. Both marker types reduced avian collision mortality by …

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Identification Of Segregating Haplotypes Of The Major Histocompatibility Complex In Cranes, Susan I. Jarvi, George F. Gee, W. Elwood Briles, Marcia M. Miller Jan 1992

Identification Of Segregating Haplotypes Of The Major Histocompatibility Complex In Cranes, Susan I. Jarvi, George F. Gee, W. Elwood Briles, Marcia M. Miller

Proceedings of the North American Crane Workshop

The major histocompatibility complex (Mhc) is thought to exist in all vertebrate species. In most species, a high degree of polymorphism is maintained in this region at mUltiple loci which encode molecules that serve in the presentation of foreign antigens to T lymphocytes (Klein 1986, Miller 1991). In this investigation, serological and recombinant DNA techniques are being used to investigate genetic diversity at the Mhc in several species of cranes, to investigate questions of paternity in some instances, and to develop practical methods for determining Mhc haplotype •. Blood samples are provided by the Patuxent Wildlife Research Center (PWRC), Laurel, …

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Whooping Crane Riverine Roosting Habitat Suitability Model, Jerry W. Ziewitz Jan 1992

Whooping Crane Riverine Roosting Habitat Suitability Model, Jerry W. Ziewitz

Proceedings of the North American Crane Workshop

Water development interests on the Platte River in Nebraska and recognition of the importance of this river as migratory bird habitat have prompted studies to determine how much water is needed to maintain wildlife habitat values. The whooping crane (Grus americana) is one of many species that use the Platte. A model was developed to quantify the relationship between river discharge and roosting habitat suitability for whooping cranes, designed to accommodate the data collection and hydraulic simulation techniques of the Instream Flow Incremental Methodology. Results of the model indicate that optimum roosting habitat conditions in the Big Bend …

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Distribution Of Color-Marked Greater Sandhill Cranes Banded In Utah, Spyros S. Manes, Roderick C. Drewien, Joel D. Huener, Thomas W. Aldrich, Wendy M. Brown Jan 1992

Distribution Of Color-Marked Greater Sandhill Cranes Banded In Utah, Spyros S. Manes, Roderick C. Drewien, Joel D. Huener, Thomas W. Aldrich, Wendy M. Brown

Proceedings of the North American Crane Workshop

Twenty-eight greater sandhill cranes (Grus canadensis tabida) were banded and color-marked on nesting grounds in northern and central Utah during summers 1986 and 1987. Sixteen were observed 1 or more times between October 1986 and February 1988 on migration, winter and summer areas. Marking studies showed that cranes nesting east and southeast of the Great Salt Lake in northern and central Utah are affiliated with the Rocky Mountain population, with most individuals migrating during the spring and fall through the San Luis Valley, Colorado and wintering in southcentral and southwestern New Mexico, southeastern Arizona and possibly northern Mexico. …

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Temporal Patterns Of Sandhill Crane Roost Site Use In The Platte River, Bradley S. Norling, Stanley H. Anderson, Wayne A. Hubert Jan 1992

Temporal Patterns Of Sandhill Crane Roost Site Use In The Platte River, Bradley S. Norling, Stanley H. Anderson, Wayne A. Hubert

Proceedings of the North American Crane Workshop

Temporal patterns of daily arrival and departure of sandhill cranes (Grus canadensis) at roost sites were examined along the Platte River in Nebraska during spring 1990. Departure times were earliest and arrival times were latest during the beginning of the 8taging season (9-21 March). Date within the staging season was the primary variable associated with time of initial departure and arrival, but arrival and departure times were also influenced by climatic factors. Departure times correlated positively with fog and precipitation (P < 0.05) and negatively with air temperature (P < 0.05), whereas arrival times correlated positively with both cloud cover and air temperature (P < 0.05).

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Winter Release Of Isolation-Reared Greater Sandhill Cranes In South Texas, Meenakshi Nagendran Jan 1992

Winter Release Of Isolation-Reared Greater Sandhill Cranes In South Texas, Meenakshi Nagendran

Proceedings of the North American Crane Workshop

During the summer of 1988, 7 greater sandhill cranes (Grus canadensis tabida) hatched from 15 eggs collected at Seney National Wildlife Refuge (NWR), Michigan, were isolation-reared at Welder Wildlife Refuge (WWR) near Sinton, Texas, and fitted with radio transmitters prior to fledging. Because of severe drought conditions on WWR. 3 surviving juveniles were moved to Laguna Atascosa NWR (LANWR) in south Texas and released on 27 January 1989. On 12 March 1989 they left LANWR with 3 wild cranes. They were relocated on 4 April in Rosebud, Texas. The 3 cranes were captured and transported to Grand Island, …

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Prevention Of Eastern Equine Encephalitis Virus In Captive Cranes, James W. Carpenter, Douglas M. Watts, C. L. Crabbs, Gary G. Clark, Thomas W. Scott, Douglas Docherty, Benedict B. Pagac, Jeannine M. Dorothy, James G. Olson, F. Joshua Dein Jan 1992

Prevention Of Eastern Equine Encephalitis Virus In Captive Cranes, James W. Carpenter, Douglas M. Watts, C. L. Crabbs, Gary G. Clark, Thomas W. Scott, Douglas Docherty, Benedict B. Pagac, Jeannine M. Dorothy, James G. Olson, F. Joshua Dein

Proceedings of the North American Crane Workshop

An epizootic of eastern equine encephalitis (EEE) virus infection in 1984 resulted in death for 7 of 39 captive whooping cranes (Grus americana) at the Patuxent Wildlife Research Center. This represented the first known whooping crane deaths associated with this arboviral disease and posed a serious risk to the continued propagation of this endangered species. Subsequent research and surveillance procedures initiated to prevent EEE viral infections in captive whooping cranes included vector surveillance and control, virus surveillance through use of sentinel birds, immunoassays for rapid detection of EEE virus antigen in bird sera and in mosquitoes, and testing …

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Distribution Of Sandhill Cranes In The North Platte River Valley: 1980 And 1989, Martin J. Folk, Thomas C. Tacha Jan 1992

Distribution Of Sandhill Cranes In The North Platte River Valley: 1980 And 1989, Martin J. Folk, Thomas C. Tacha

Proceedings of the North American Crane Workshop

We observed the abundance, diurnal distribution, and habitat use of sandhill cranes (Grus canadensis) in the North Platte River Valley (NPRV) in 1989 for comparisons to similar data from 1979 to 1980. Sandhill cranes traveled farther from nocturnal roosts to diurnal feeding sites and use of the NPRV was lower in 1989 as compared to 1979~80. Presence of cranes in corn stubble and pasture increased from 1980 to 1989, while presence in alfalfa and palustrine wetlands decreased. Plowing of corn stubble fields and drought conditions in 1989 may have influenced crane distribution, abundance, and habitat use.

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Factors Influencing The Future Of Whooping Crane Habitat On The Platte River In Nebraska, Craig A. Faanes Jan 1992

Factors Influencing The Future Of Whooping Crane Habitat On The Platte River In Nebraska, Craig A. Faanes

Proceedings of the North American Crane Workshop

Lands along 86 km of the Platte River in Nebraska were designated by the U.s. Department of Interior as critical habitat for the endangered whooping crane (Grus americana) in 1978. The designation established the legal basis for the continued protection of lands critical to the survival and recovery of whooping cranes. Currently there are 14 federal, state, and local water projects planned for the Platte River system. If completed, total withdrawal would be about 80% of the remaining 30% of the original flow. In this paper I summarize those projects and discuss their potential impact on whooping crane habitat. …

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Distribution And Status Of Greater Sandhill Cranes In Nevada, Marcus S. Rawling Jan 1992

Distribution And Status Of Greater Sandhill Cranes In Nevada, Marcus S. Rawling

Proceedings of the North American Crane Workshop

Nesting habitat of the Lower Colorado River Valley Population (LCRVP) of greater sandhill cranes (Grus canadensis tabida) was censused in northeastern Nevada from 1983 through 1986. Ninety-two nesting pairs and 594 cranes were located. Eighty-two percent were observed in central Elko County. Cranes were marked from 2 summer range locations and from the Lund, Nevada traditional spring migration stopover with patagial streamers. Cranes marked on summer range wintered on the lower Colorado River, in the Imperial Valley near Brawley, California and on the Gila River in southwestern Arizona. Cranes marked at the stopover were observed on summer range …

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Individual Identification And Sex Determination Of Whooping Cranes By Analysis Of Vocalizations, Glenn Carlson Jan 1992

Individual Identification And Sex Determination Of Whooping Cranes By Analysis Of Vocalizations, Glenn Carlson

Proceedings of the North American Crane Workshop

I analyzed 3 temporal and 2 frequency features of whooping crane (Grus americana) guard calls from 4 locations to determine if vocalizations could be used as a means of sex determination and individual identification in this species. Wild birds were recorded at Grays Lake, Idaho, and Aransas National Wildlife Refuge, Texas, and captive birds were recorded at Patuxent Wildlife Research Center, Maryland, and the International Crane Foundation, Wisconsin. Discriminant analysis provided an overall success rate of 98.8% in classifying individual calls to the appropriate sex of Whooping crane. This success rate is comparable to that of the current …

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The Ecology Of Native Grassland Macroinvertebrates And Feeding Ecology Of Sandhill Cranes, Craig A. Davis, Paul A. Vohs Jan 1992

The Ecology Of Native Grassland Macroinvertebrates And Feeding Ecology Of Sandhill Cranes, Craig A. Davis, Paul A. Vohs

Proceedings of the North American Crane Workshop

The ecology of native grassland macroinvertebrates along the Platte River in central Nebraska and their role in the feeding ecology of sandhill cranes (Grus canadensis) was examined on 3 native grasslands along the Platte River during late winter-early spring, 1989 and 1990. Four hundred forty-four soil samples from the study area were sorted for macroinvertebrates. Environmental factors such as soil moisture, water table depth, soil texture, and plant species composition were recorded from each soil collection site. Fifteen sandhill cranes, observed feeding for 40 minutes, were collected from 1 of the study areas. Maeroinvertebrates were collected from 4 …

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Black-Necked Cranes Nesting In Tibet Autonomous Region, China, Nancy C. Dwyer, Mary Anne Bishop, Jim S. Harkness, Zhang Yao Zhong Jan 1992

Black-Necked Cranes Nesting In Tibet Autonomous Region, China, Nancy C. Dwyer, Mary Anne Bishop, Jim S. Harkness, Zhang Yao Zhong

Proceedings of the North American Crane Workshop

Between 7 May and 5 August 1991 we counted 298 black-necked cranes (Grus nigricollis) on breeding grounds in central and southwestern Tibet Autonomous Region (TAR). We confirmed breeding for 32 pairs: we found 17 nests at 8 wetland sites and 15 broods of 25 chicks, including 5 transitional fledglings. Mean altitude of nest wetlands was 4694 m. Nest height averaged 21.3 em above water, and water depth averaged 14.8 em. Black-necked cranes nested a mean of 140.5 m from uplands and 803 m from potential disturbance such as a road or dwelling. Mean nest initiation date was 28 …

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Population Recovery Of The Whooping Crane With Emphasis On Reintroduction Efforts: Past And Future, David H. Ellis, James C. Lewis, George F. Gee, Dwight G. Smith Jan 1992

Population Recovery Of The Whooping Crane With Emphasis On Reintroduction Efforts: Past And Future, David H. Ellis, James C. Lewis, George F. Gee, Dwight G. Smith

Proceedings of the North American Crane Workshop

The U.S. Fish and Wildlife Service (USFWS) began building a captive whooping crane (Grus americana) colony at Patuxent Wildlife Research Center (patuxent), Maryland, in 1966. From 1976 to 1984, 73 eggs from this colony and 216 eggs from Wood Buffalo National Park (Wood Buffalo), Canada, nests were placed in sandhill crane (G. canadensis) nests at Grays Lake National Wildlife Refuge (Grays Lake), Idaho, the site of the first whooping crane reintroduction attempt. Although 84 chicks fledged from the 289 eggs, the egg transfer program has been discontinued because of inordinately high mortality (only ca. 13 birds remain …

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Satellite Telemetry Reveals Winter Home Of Eurasian Crane From Northwestern Siberia, David H. Ellis, Yuri M. Markin, Charles H. Vermillion, Charles M. Hoisington, Alexander G. Sorokin, Grey W. Pendleton Jan 1992

Satellite Telemetry Reveals Winter Home Of Eurasian Crane From Northwestern Siberia, David H. Ellis, Yuri M. Markin, Charles H. Vermillion, Charles M. Hoisington, Alexander G. Sorokin, Grey W. Pendleton

Proceedings of the North American Crane Workshop

Satellite telemetry is a developing technology for the study of crane migration. A greater sandhill crane (Grus canadensis tabida) was tracked by satellite from Florida to Michigan in March 1989 (Nagendran 1992). This note reports the second attempt to use satellite telemetry to follow crane migration. In 1989 -90, tests of various harness and backpack designs for satellite telemetry transmitters (PTT's) with free-flying and confined sandhill cranes led to a 4-strap design (see Olsen et al. 1992) that was accepted for field testing. Through a cooperative effort between the Patuxent Wildlife Research Center (USFWS) , International Crane Foundation, …

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Techniques For Rearing And Releasing Nonmigratory Cranes: Lessons From The Mississippi Sandhill Crane Program, David H. Ellis, Glenn H. Olsen, George F. Gee, Jane M. Nicolich, Kathleen E. O'Malley, Meenakshi Nagendran, Scott G. Hereford, Peter Range, W. Thomas Harper, Richard P. Ingram, Dwight G. Smith Jan 1992

Techniques For Rearing And Releasing Nonmigratory Cranes: Lessons From The Mississippi Sandhill Crane Program, David H. Ellis, Glenn H. Olsen, George F. Gee, Jane M. Nicolich, Kathleen E. O'Malley, Meenakshi Nagendran, Scott G. Hereford, Peter Range, W. Thomas Harper, Richard P. Ingram, Dwight G. Smith

Proceedings of the North American Crane Workshop

Captive-reared Mississippi sandhill cranes (Grus canadensis pulla) reared at the Patuxent Wildlife Research Center (patuxent) have been released at the Mississippi Sandhill Crane National Wildlife Refuge (MSCNWR) since 1981. Of 131 birds released through December 1990, 103 were reared by foster parents. The remaining 28 were experimentally hand-reared in 1989 and 1990. After refining release procedures, parent-reared birds have integrated into the wild flock, many have survived, and some have bred. Releases of hand-reared cranes elsewhere in the 1970's were largely unsuccessful. at least in part due to the lack of a lengthy acclimation period. A new hand-rearing …

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Characteristics Of Whooping Crane Roost Sites In The Platte River, Craig A. Faanes, Douglas H. Johnson, Gary R. Lingle Jan 1992

Characteristics Of Whooping Crane Roost Sites In The Platte River, Craig A. Faanes, Douglas H. Johnson, Gary R. Lingle

Proceedings of the North American Crane Workshop

The Big Bend of the Platte River in centraJ Nebraska provides important migration habitat for whooping cranes (Grus americana). River profiles were obtained at 23 confumed nocturnal roost sites occupied by whooping cranes during 1983 -90. Whooping cranes selected roost sites that had shallower water depths than at unused sites. All but 4 roosts were located in channels wider than 150 m; roost sites were an average of 27.8 % of the channel width from the nearer shore. Nearly 90% of the roost sites had a trench of deeper water on both sides. Proper management of the Platte …

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Whooping Cranes In Southwest Louisiana: History And Human Attitudes, Gay M. Gomez Jan 1992

Whooping Cranes In Southwest Louisiana: History And Human Attitudes, Gay M. Gomez

Proceedings of the North American Crane Workshop

When whooping cranes (Grus americana) inhabited southwest Louisiana's coastal marshes, residents viewed them as a food source and a crop pest, and shooting was commonplace. Local attitudes have changed as a result of education, stricter law enforcement, and decreased dependence on wildlife for subsistence, but hunting remains widespread. A 1977 proposal to reintroduce whooping cranes to southwest Louisiana generated strong opposition from the Louisiana Wild Life and Fisheries Commission (now Louisiana Department of Wildlife and Fisheries), based on concerns about critical habitat and its likely impact on waterfowl hunting and other traditional marsh uses. These concerns remain, though …

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The Plight Of Cranes: A Case Study For Conserving Biodiversity, J. Christopher Haney, Mark E. Eiswerth Jan 1992

The Plight Of Cranes: A Case Study For Conserving Biodiversity, J. Christopher Haney, Mark E. Eiswerth

Proceedings of the North American Crane Workshop

Cranes provide an exemplary case for evaluating conservation policy because (1) they are a charismatic group with high public visibility, (2) as migratory vertebrates they provide an umbrella for the protection of aquatic habitats and a wider set of species, (3) they are a widely-distributed avian family, consequently protection efforts have favored international cooperation, (4) genetic and taxonomic relationships have been studied, and (5) populations of at least 7 crane species are threatened, endangered, or otherwise considered at direct risk. We use comparisons among the world's cranes to show how biogeographic, taxonomic, and genetic data bases can be linked for …

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Managing Nature Reserves For Cranes In China, James Harris Jan 1992

Managing Nature Reserves For Cranes In China, James Harris

Proceedings of the North American Crane Workshop

During the past 15 years, China has established more than 300 nature reserves. Many of the wetland reserves have been created primarily to protect endangered cranes. This paper summarizes the status of 22 nature reserves, 13 for breeding cranes and 9 for wintering cranes. The nature reserves have often been established in areas heavily populated or intensively used for economic purposes. Many reserves have been effective in stopping hunting of cranes. Taking of eggs or young has also been greatly reduced, but general human disturbances threaten successful nesting. Reserve authorities have also taken steps to prevent destruction or degradation of …

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Whooping Crane Response To Disturbances At The Aransas National Wildlife Refuge, Thomas E. Lewis, R. Douglas Slack Jan 1992

Whooping Crane Response To Disturbances At The Aransas National Wildlife Refuge, Thomas E. Lewis, R. Douglas Slack

Proceedings of the North American Crane Workshop

Many forms of disturbance on and near the Aransas National Wildlife Refuge cause disruptions to wintering whooping cranes (Grus americana). Known forms of disturbance include various boating, aircraft, and automobile traffic. Natural disturbance from other wildlife also occurs. Behavioral observations and disturbance documentation have shown that Whooping cranes respond differently to various disturbances. Although airplane overflights, recreational boating, barge traffic. and workboat activity represent the most frequent disturbances to whooping cranes (22, 19, 14, and 13 %, respectively, of total disturbances), it appears that frequency of occurrence is less important than the disturbance class and distance from the …

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History And Economic Impact Of Crane-Watching In Central Nebraska, Gary R. Lingle Jan 1992

History And Economic Impact Of Crane-Watching In Central Nebraska, Gary R. Lingle

Proceedings of the North American Crane Workshop

The first documentation of the Platte and North Platte rivers' importance to sandhill cranes (Grus canadensis) dates from the late 1800's. Except for a few ornithologists, it was not until the mid-1970's that crane-watching became popular. During the last 10 years, this interest has become a multi-million dollar tourist industry that attracts people from around the globe who seek to witness this vernal spectacle of half a million cranes. More than half of the former riverine habitat has been abandoned by the cranes, largely because of irrigation and hydropower projects that drain the river and enable forests to …

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Sandhill Cranes In The Mid·Pecos Valley Of Eastern New Mexico, 1989–91, James B. Montgomery Jan 1992

Sandhill Cranes In The Mid·Pecos Valley Of Eastern New Mexico, 1989–91, James B. Montgomery

Proceedings of the North American Crane Workshop

Weekly roost counts and observations of flock movements and field use were conducted during winters of 1989 -90 and 1990-91 to determine the status of sandhill cranes (Grus canadensis) in the RoswelllBitter Lake National Wildlife Refuge region of the Pecos River Valley of eastern New Mexico. Cranes roost on shallow lakes along the Pecos River, both on and off the refuge, and rely on approximately 36,000 ha of mostly irrigated farmland for foraging. During the past decade, alfalfa production has increased to 20,000 ha and corn production has decreased to 2,000 ha, of which 98 % is cut …

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Behavior Of Sandhill Cranes Near Power Lines Marked With Yellow Aviation Balls, Anne E. Morkill, Stanley H. Anderson Jan 1992

Behavior Of Sandhill Cranes Near Power Lines Marked With Yellow Aviation Balls, Anne E. Morkill, Stanley H. Anderson

Proceedings of the North American Crane Workshop

The principal known cause of mortality for wild whooping cranes (Grus americana) is collision with powerlines. Methods to minimize powerline collisions will contribute to the species' long term recovery. We studied the flight behavior of sandhill cranes (G. canadensis) near powerlines marked with yellow aviation balls near the Platte River, Nebraska, in 1988-90. An age ratio of 24 juveniles:76 adults of 84 carcasses found under powerlines was significantly different from typical population ratios of 12: 88 for this species. Two-way contingency table analysis of crane flight behavior data indicated that cranes avoided markers (P < 0.(01), reducing the potential for collision. Proximity ofpowerlines to habitats used by cranes (P < 0.001), wind speed (P < 0.05), and age of bird (P < 0.(01) were important factors contributing to crane collisions with powerlines in Nebraska. Details are available in Wildl. Soc. Bull. 19(4):442-449.

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Gender Prediction From Body Measurements Of Two Subspecies Of Sandhill Cranes, Stephen A. Nesbitt, Clinton T. Moore, Kathleen S. Williams Jan 1992

Gender Prediction From Body Measurements Of Two Subspecies Of Sandhill Cranes, Stephen A. Nesbitt, Clinton T. Moore, Kathleen S. Williams

Proceedings of the North American Crane Workshop

Linear discriminant functions estimated from leg length, bill length and body weight measurements of known subspecies and known gender (KS-KG) Florida (FSH) and greater sandhill cranes (GSH) (Grus canadensis pratensis and G. c. tabida, respectively) were used to predict gender of known subspecies and unknown gender (KS-UG) individuals. Mean body measurements were larger among males than among females of either subspecies, but the difference in mean bill length between genders was larger among GSH than among FSH cranes. Gender misclassification was less frequent among GSH than among FSH cranes. Of birds whose measurements fell outside of the 80% …

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