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Proceedings Of The Sixth North American Crane Workshop Jan 1992

Proceedings Of The Sixth North American Crane Workshop

Proceedings of the North American Crane Workshop

In 1975 a group of North American crane researchers and managers convened a workshop at the fledgling International Crane Foundation in Baraboo, Wisconsin. At the end they agreed to publish the proceedings of the workshop and to reconvene in 3 years to continue to share information, ideas, and support. Workshops followed in 1978 (Rockport, Texas), 1981 (Grand Teton National Park, Wyoming), 1985 (Grand Island, Nebraska), and 1988 (Kissimmee Prairie, Florida). At the Florida meeting this loose-knit group agreed to form the North American Crane Working Group (NACWG), an organization of "professional biologists, aviculturists, land managers, and other interested individuals dedicated …


Sexual Size Dimorphism And Size Indices Of Six Species Of Captive Cranes At The International Crane Foundation, Scott R. Swengel Jan 1992

Sexual Size Dimorphism And Size Indices Of Six Species Of Captive Cranes At The International Crane Foundation, Scott R. Swengel

Proceedings of the North American Crane Workshop

Sexual size dimorphism and size indices in captive cranes were studied to learn dimorphism patterns and size relationships that could be used in the management of captive cranes. In 6 species of captive cranes. Siberian (Grus leucogeranus), eastern sarus (G. antigone sharpir), white-naped (G. vipio), common (G. grus), hooded (G. monacha), and red-crowned (G. japonensis), maIes averaged 14.5-28.5% heavier than femaIes (P < 0.05) in all species. MaIes had longer culmens, tarsi, and wing chords in all species. MaIes had significantly longer culmens (P < 0.05) in 4 of 6 species and had significantly longer tarsi than females (P < 0.05) in 3 of 6 species. Culmen and tarsus lengths both averaged 7% longer in males than females when the 6 species were combined. Wing chord length was not significantly dimorphic (P > 0.05) in any of the 4 species measured (Siberian, white-naped, hooded, and red-crowned cranes), averaging only 1.3 -3.3 % longer in males than in females. Body …


Dispersal Of Pen-Reared Mississippi Sandhill Cranes, Phillip J. Zwank, Donna A. Dewhurst Jan 1992

Dispersal Of Pen-Reared Mississippi Sandhill Cranes, Phillip J. Zwank, Donna A. Dewhurst

Proceedings of the North American Crane Workshop

Dispersal patterns of juvenile parent-reared, captive produced Mississippi sandhill cranes (grus canadensis pulla) were monitored using radiotelemetry. Dispersal chronology and distance traveled by cranes differed among 4 releases and seemed to be influenced by rearing methods. Most cranes that had been placed in communal pens before release formed flocks when released. Cranes released without communal pen experience did not flock, but individually associated with native cranes. Nonflocking released cranes dispersed more rapidly and to a greater distance, but had lower survival.


Satellite Tracking Of A Greater Sandhill Crane, Meenakshi Nagendran Jan 1992

Satellite Tracking Of A Greater Sandhill Crane, Meenakshi Nagendran

Proceedings of the North American Crane Workshop

The first satellite transmitter (PTT) to be used on a wild crane was deployed on an isolation-reared greater sandhill crane (Grus canadensis tabida) colt in south Texas on 6 November 1988. The 160-g transmitter required more than 8 hours of direct sunlight for the solar cells to recharge the NiCad battery power supply. Signal repetition rate was once every 60 seconds. National Oceanic and Atmospheric Agency satellites in polar orbits, equipped with Argos instruments, received PIT signals via a doppler shift mechanism. Information included location of PTT (bird), long-term activity, short-term activity, and ambient temperature. The crane colt …


Effects Of Extended On Sandhill Crane Reproduction, George F. Gee, Grey W. Pendleton Jan 1992

Effects Of Extended On Sandhill Crane Reproduction, George F. Gee, Grey W. Pendleton

Proceedings of the North American Crane Workshop

Photoperiod studies were conducted with greater sandhill cranes (Grus canadensis tabida) from 1969 to 1972 and from 1982 to 1987 at the Patuxent Wildlife Research Center, Maryland. When housed indoors and exposed to long photoperiods, males produced semen during winter. When exposed to artificially extended photoperiods during spring in outdoor pens, females apparently laid earlier in the year and laid more eggs than they would have without the added light. Cranes did not exhibit any signs of photo refractory response to extended photo periods.


Capturing Whooping Cranes And Sandhill Cranes By Night-Lighting, Roderick C. Drewien, Kent R. Clegg Jan 1992

Capturing Whooping Cranes And Sandhill Cranes By Night-Lighting, Roderick C. Drewien, Kent R. Clegg

Proceedings of the North American Crane Workshop

We caught 19 adult (> 1.5 years old) whooping craoes (Grus americana) in 84 capture attempts (23 % success) by nightlighting during 1981-91 in Idaho, Wyoming, and New Mexico, including 17 for experimental purposes and 2 that were debilitated (aviao cholera aod lead poisoning). We also captured 250 greater saodhill craoes (G. canadensis tabida), including 157 adults aod 93 juveniles, on summer areas at Grays Lake National Wildlife Refuge, Idaho, to color-mark them for behavioral and movement studies. Night-lighting equipment included an 8.5-kg portable generator mounted on an aluminum back-pack frame and a 12- or 28-V …


Habitat Use By Greater Sandhill Cranes In Wyoming, Mary M. Rowland, Lynn Kinter, Tim Banks, David C. Lockman Jan 1992

Habitat Use By Greater Sandhill Cranes In Wyoming, Mary M. Rowland, Lynn Kinter, Tim Banks, David C. Lockman

Proceedings of the North American Crane Workshop

Wyoming suppors approximately 20% of the Rocky Mountain population (RMP) of greater sandhill cranes (Grus canadensis tabida), as well as a number of whooping cranes (Grus americana) from the Grays Lake, Idaho flock. Cranes begin arriving on post-migration staging areas in Wyoming in mid-March and disperse to summer habitat in April or May, depending on snow cover. Fall pre-migration, staging peaks around mid-September; most cranes leave the state by 1 October. Wet meadows and gram fIelds were the major habitat types used by cranes in Wyoming 1985-1987. Use in these types ranged from 69- 100% of …


Proceedings 1988 North American Crane Workshop Jan 1992

Proceedings 1988 North American Crane Workshop

Proceedings of the North American Crane Workshop

What follows is the published product of the fifth North American Crane Workshop held February 22-24, 1988, at River Ranch Outdoor Resort, Lake Wales, Florida. These papers were among the 52 given during that workshop. Also at this meeting, the North American Crane Working Group came into being with the election of a board of directors and the group's first president, Gary Lingle. Among other things, the working group will oversee and lend continuity to future workshops and the publication of the proceedings.

The meeting was organized by the Florida Game and Fresh Water Fish Commission with support from the …


Mortality In Fledged Whooping Cranes Of The Aransas/Wood Buffalo Population, James C. Lewis, Ernie Kuyt, Kenneth E. Schwindt, Thomas V. Stehn Jan 1992

Mortality In Fledged Whooping Cranes Of The Aransas/Wood Buffalo Population, James C. Lewis, Ernie Kuyt, Kenneth E. Schwindt, Thomas V. Stehn

Proceedings of the North American Crane Workshop

A total of 1,893 whooping cranes (Grus americana) overwintered at Aransas National Wildlife Refuge from 1950 through spring 1987. Winter losses (dead and disappeared) amounted to only 1.3% of the population, but 3.7% of the juveniles. About 19% of the annual losses occurred in the wintering area where birds spend 5 to 6 months of the year. Eighty-one percent of the losses occurred from April to November. Losses on the summering area appear to be low. The most significant losses seem to occur during migration and may comprise between 60 and 80% of the annual losses. Migration involves …


Behavior Of Sandhill Cranes Harnessed With Different Satellite Transmitters, Glenn H. Olsen, David H. Ellis, Steven E. Landfried, Linda M. Miller, Susan S. Klugman, Charles H. Vermillion Jan 1992

Behavior Of Sandhill Cranes Harnessed With Different Satellite Transmitters, Glenn H. Olsen, David H. Ellis, Steven E. Landfried, Linda M. Miller, Susan S. Klugman, Charles H. Vermillion

Proceedings of the North American Crane Workshop

The effectiveness of various attachment methods and designs of platform transmitting terminals (PIT's) was tested on captive sandhill cranes (Grus canadensis) at the Patuxent Wildlife Research Center, Laurel, Maryland, during 1989-91. Combinations of attachment and transmitter designs included neoprene cord harness with batteries separate from the transmitter (2 harness designs), Teflon ribbon harness with batteries incorporated into the transmitter package (4 transmitter models), and a package attached directly to the bird with epoxy glue only. Physical effects seen on cranes wearing PTT's ranged from skin lacerations (caused by rubbing of harness material) to no observed effects (other than …


Karyotype And Identification Of Sex In Two Endangered Crane Species, Carll Goodpasture, Gustavo Seluja, George Gee Jan 1992

Karyotype And Identification Of Sex In Two Endangered Crane Species, Carll Goodpasture, Gustavo Seluja, George Gee

Proceedings of the North American Crane Workshop

A laboratory procedure for sex identification of monomorphic birds was developed using modern cytological methods of detecting chromosome abnormalities in human amniotic fluid samples. A pin feather is taken from a pre-fledging bird for tissue culture and karyotype analysis. Through this method, the sex was identified and the karyotype described of the whooping crane (Grus americana) and the Mississippi sandhill crane (G. canadensis pulla). Giemsa-stained karyotypes of these species showed an identical chromosome constitution with 2n = 78 ± 2. However, differences in the amount of centromeric heterochromatin were observed in the Mississippi sandhill crane when …


An Individualized Marking Scheme For Sandhill Cranes And Its Use To Determine Fall Migration Interval, Stephen A. Nesbitt, Robin D. Bjork, Kathleen S. Williams, Stephen T. Schwikert, Anne S. Wenner Jan 1992

An Individualized Marking Scheme For Sandhill Cranes And Its Use To Determine Fall Migration Interval, Stephen A. Nesbitt, Robin D. Bjork, Kathleen S. Williams, Stephen T. Schwikert, Anne S. Wenner

Proceedings of the North American Crane Workshop

A color-band based marking scheme was used for individually marking sa ndhill cranes in Florida. The band-loss rate was 2.8% per year between 1977 and 1988. Band loss was greatest on bands placed below the ankle joint and occurred most frequently during years 2 to 5. Color-marked individuals monitored during fall migration averaged 6.2 days (r=5-13 days) between the Jasper-Pulaski Fish and Wildlife area in northwestern Indiana and winlering areas in northern Florida.


Development Of An Isolation-Rearing/Gentle Release Procedure For Reintroducing Migratory Cranes, Richard P. Urbanek, Theodore A. Bookhout Jan 1992

Development Of An Isolation-Rearing/Gentle Release Procedure For Reintroducing Migratory Cranes, Richard P. Urbanek, Theodore A. Bookhout

Proceedings of the North American Crane Workshop

During 1988 -90, in an effort to develop a reintroduction technique for the whooping crane (Grus americana), we reared 38 greater sandhill crane chicks (G. canadensis tabida) in isolation from humans and gentle-released them on Seney National Wildlife Refuge (NWR) in the Upper Peninsula of Michigan. Chicks were reared in the field with a puppet/costume technique. After chicks completed acclimation to wild conditions in a release pen, we induced them to migrate by breaking their flock into small groups, translocating some groups, and using guide birds. Solutions to migration initiation problems encountered in 1988-89 were developed …


Contaminant Residues In Sandhill Cranes Killed Upon Striking Powerlines In Central Nebraska, Timothy E. Fannin Jan 1992

Contaminant Residues In Sandhill Cranes Killed Upon Striking Powerlines In Central Nebraska, Timothy E. Fannin

Proceedings of the North American Crane Workshop

In 1989 and 1990, 58 sandhill cranes (Grus canadensis) were collected along the central Platte River in Nebraska during a study of mortality caused by powerline impact. Brains were assayed for acetylcholinesterase activity; gut contents were analyzed for residues of 25 organophosphate and 6 carbamate compounds; and livers were analyzed for 20 inorganics (including lead, mercury, and boron) and 22 organochlorine chemicals. Brain acetylcholinesterase activities appeared to be within normal ranges, and no measurable organophosphate or carbamate residues were found in the gut contents of 5 birds with the lowest brain enzyme activities. Heptachlor epoxide, oxychlordane. p,p' -DDE, …


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 …


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 …


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 …


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 …


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.


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 …


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, …


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 …


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. …


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).


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, …


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 …


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.


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. …


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 …


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 …