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Spring Population Estimates Of Rocky Mountain Greater Sandhill Cranes In Colorado, Douglas S. Benning, Roderick C. Drewien, Douglas H. Johnson, Wendy M. Brown, Erwin L. Boeker Jan 1997

Spring Population Estimates Of Rocky Mountain Greater Sandhill Cranes In Colorado, Douglas S. Benning, Roderick C. Drewien, Douglas H. Johnson, Wendy M. Brown, Erwin L. Boeker

Proceedings of the North American Crane Workshop

We developed an aerial survey to estimate the Rocky Mountain Population (RMP) of greater sandhill cranes (Grus canadensis tabidn) (greaters) annually during March 1984-95 in the San Luis Valley, Colorado (SLV). We flew aerial transects covering a 21,220-ha contiguous area. Aerial photographs of crane flocks were taken to correct for estimation errors. We employed ground surveys to correct for presence of lesser sandhill cranes (G. c. canadensis) (lessers), which mixed with RMP cranes. To adjust for RMP cranes not in the survey area, we made ground counts in traditional use areas outside the SLY. During 1984-95, 5 …


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% …


Mortality Of Radio-Equipped Sandhill Crane Colts At Malheur National Wildlife Refuge, Oregon, Gary L. Ivey, Eric J. Scheuering Jan 1997

Mortality Of Radio-Equipped Sandhill Crane Colts At Malheur National Wildlife Refuge, Oregon, Gary L. Ivey, Eric J. Scheuering

Proceedings of the North American Crane Workshop

We radio-equipped 142 greater sandhill crane (Grus canadensis tabida) colts at Malheur National Wildlife Refuge, Oregon, during 1991-95 to document prefledging mortality factors. Fates of 19 colts were undetermined. A total of 23 colts survived to fledge (19% of known fates). Evidence collected from the carcasses and death sites indicated that predators were responsible for the largest number of colt deaths (64), followed by unknown causes (13), parasitic gapeworms (Cyastoma spp.) (8), drowning (7), intraspecific aggression (5), study-related mortality (I), roadkill (I), and hay swather (1). Of 64 colts killed by predators, 26 were lost to mink …


Use Of Dredged Material To Construct Winter Whooping Crane Habitat, Darrell E. Evans, Thomas V. Stehn Jan 1997

Use Of Dredged Material To Construct Winter Whooping Crane Habitat, Darrell E. Evans, Thomas V. Stehn

Proceedings of the North American Crane Workshop

Aransas National Wildlife Refuge (ANWR) and nearby coastal marshes serve as the winter home for the only natural flock of whooping cranes (Grus americana), In recent years shoreline erosion and the subsequent loss of wintering habitat have been observed on the refuge adjacent to the GulfIntracoastal Waterway (GIWW). In 1988 the U.S. Army Corps of Engineers (USACE) District, Galveston, Texas, and U.S. Fish and Wildlife Service (USFWS) entered into an informal agreement to attempt to slow shoreline/habitat loss on the refuge. Efforts to curtail habitat loss have included armoring the most erosive reaches with temporary concrete erosion control …


The Effect Of Disturbance On The Reproduction And Management Of Captive Cranes, Claire M. Mirande, James W. Carpenter, Ann M. Burke Jan 1997

The Effect Of Disturbance On The Reproduction And Management Of Captive Cranes, Claire M. Mirande, James W. Carpenter, Ann M. Burke

Proceedings of the North American Crane Workshop

A retrospective analysis of egg laying histories and observations of crane pairs at the International Crane Foundation and the Patuxent Wildlife Research Center indicates that disturbance associated with captivity has adverse impacts on captive breeding. Females on public display laid significantly fewer eggs than those off display (P < 0.05). Crane pairs moved to other pens (other than adjacent pens) or hetween facilities laid slightly fewer eggs than those birds which were not moved. although the results were not statistically significant (P = 0.188). Pen design and construction also appeared to have adverse impacts on breeding. In addition, human activities, intraspecific interactions, and rearing methods influence a bird's response to disturbance, and, therefore, these factors must also be considered in an effective crane management program. Modifying procedures to minimize disturbance, timing necessary disturbances after the breeding and molt seasons, and carefully monitoring birds for signs of stress can result in increased reproductive potential for captive, endangered cranes.


Subspecies Composition Of Sandhill Crane Harvest In North Dakota, 1968-94, William L. Kendall, Douglas H. Johnson, Stanley C. Kohn Jan 1997

Subspecies Composition Of Sandhill Crane Harvest In North Dakota, 1968-94, William L. Kendall, Douglas H. Johnson, Stanley C. Kohn

Proceedings of the North American Crane Workshop

North Dakota is a major fall staging area for the Mid-continent Population (MCP) of sandhill cranes (Grus canadensis), which is composed of 3 subspecies: the greater (G. c. tabida), Canadian (G. c. rawani), and lesser (G. c. canadensis). The number of cranes killed by hunters in North Dakota averaged 6,793 during the 1990-94 seasons, ranking second highest among crane-hunting states. The distribution of harvest among subspecies is important, due to concerns about the poorly known status of these subspecies, especially the greater. We estimated subspecies composition of the harvest in North Dakota by …


Sandhill Crane Use Of The Mid-Pecos Valley Of Eastern New Mexico, James B. Montgomery Jr. Jan 1997

Sandhill Crane Use Of The Mid-Pecos Valley Of Eastern New Mexico, James B. Montgomery Jr.

Proceedings of the North American Crane Workshop

Sandhill cranes (Grus canadensis) were monitored during winters 1989-94 in the mid-Pecos River Valley of eastern New Mexico to detennine how many used this region following a population decline in the 1980's. Numbers annually increased to a late October/early November peak (X = 7,017), fluctuated around 6,000 through December, declined in January (X = 3,531), and again peaked in February/early March (X = 5,737). Annual crane use-days (weekly counts X 7) varied from 500,545 to 1,007,673 (X = 760,606). Cranes foraged mainly in corn and sorghum stubble and alfalfa fields. Crop averages (ha) during 1990-92 were alfalfa 21,449, …


Monogamy And Productivity In Sandhill Cranes, Stephen A. Nesbitt, Thomas C. Tacha Jan 1997

Monogamy And Productivity In Sandhill Cranes, Stephen A. Nesbitt, Thomas C. Tacha

Proceedings of the North American Crane Workshop

Marked pairs of Florida (Grus canadensis pratensis) and greater sandhill cranes (G. c. tabida) were monitored for 426 pair-years. Among pair members, females averaged 3.7 ± 3.6 (SD) years older than males. Pair longevity was not correlated with pair productivity (P ~ 0.279) for pairs that were together >3 years. Forty-four percent of 72 Florida sandhill crane pair bonds were broken during the study, 67.7% due to death and 32.3 % to divorce. Among both Florida and greater sandhill cranes, the incidence of divorce was related to a failure to reproduce; 52.6% of pairs that failed to produce …


Whooping Crane Mortality At Patuxent Wildlife Research Center, 1982-95, Glenn H. Olsen, Joanna A. Taylor, George F. Gee Jan 1997

Whooping Crane Mortality At Patuxent Wildlife Research Center, 1982-95, Glenn H. Olsen, Joanna A. Taylor, George F. Gee

Proceedings of the North American Crane Workshop

Whooping cranes (Grus americana) have been reared at Patuxent Wildlife Research Center since 1966. During 1982-95 there were 103 mortalities caused by infectious and parasitic diseases (46%), trauma (21 %), anatomic abnormalities (17%), miscellaneous conditions (12 %) I and open or no diagnoses (5 %). The implications that disease may have on new whooping crane flocks in Florida and Canada are discussed, based on these mortality factors in captivity.


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 …


Pair Formation By Color-Marked Whooping Cranes On The Wintering Grounds, Thomas V. Stehn Jan 1997

Pair Formation By Color-Marked Whooping Cranes On The Wintering Grounds, Thomas V. Stehn

Proceedings of the North American Crane Workshop

Observations were made of color-marked whooping cranes (Grus americana) at Aransas during the 1977-94 winters. Suhadult cranes wintered near their juvenile home ranges in flocks averaging 3.12 birds. One and 2 winters prior to nesting, subadults at Aransas tended to form duos apart from other subadults. Frequencies of association 1 year prior to nesting averaged 65.4%. However, 27.7 % of pair bonds (n = 18) formed during spring migration or on the breeding grounds without any observed prior association at Aransas. Sixty-eight banded cranes formed pairs. Pair members averaged 1.06 years difference in age. Winter territories of adults …


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.


History Of Breeding Pairs And Nesting Sites Of The Mississippi Sandhill Crane, Jacob M. Valentine Jr., Scott G. Hereford Jan 1997

History Of Breeding Pairs And Nesting Sites Of The Mississippi Sandhill Crane, Jacob M. Valentine Jr., Scott G. Hereford

Proceedings of the North American Crane Workshop

Thirty-four Composite Nesting Areas (CNA's) of endangered Mississippi sandhill cranes (Grus canadensis pulla) within the current breeding range in Jackson County, Mississippi, were located from 1965 to 1996, primarily by ground searching. Of those 34 CNA's located, 28 were on I of the 3 refuge units and 6 were off but adjacent to the refuge's Ocean Springs Unit. Five of the CNA's had 2-3 distinct smaller core nesting areas within. Two CNA's had active nests in more than 20 years, and those nests accounted for 11 % of the total. Nine CNA's accounted for 130 (63%) of the …


Food And Energy Intake Rates Of Wintering Whooping Cranes Foraging On Two Selected Food Items, Felipe Chavez-Ramirez, Jay T. Nelson, R. Douglas Slack Jan 1997

Food And Energy Intake Rates Of Wintering Whooping Cranes Foraging On Two Selected Food Items, Felipe Chavez-Ramirez, Jay T. Nelson, R. Douglas Slack

Proceedings of the North American Crane Workshop

Number, mass, and potential energy of food items consumed by wintering whooping cranes (Grus americana) foraging on blue crab (Callinectes sapidus) and woltberry (Lycium carolinianum) fruit were estimated and compared between 2 consecutive winter periods. Mass consumed was determined through field observations by quantifying the number of items taken per unit time and the average, or modal, weight of each food item determined from collections. Gross energy intake was determined by calculating the product of mass consumed times gross energy (kJ/g) of each food item. Potential energy retained was calculated by determining metabolizable energy …


Results Of Eight Years Of Predator Control To Enhance Sandhill Crane Production On Malheur National Wildlife Refuge, Oregon, Gary L. Ivey Jan 1997

Results Of Eight Years Of Predator Control To Enhance Sandhill Crane Production On Malheur National Wildlife Refuge, Oregon, Gary L. Ivey

Proceedings of the North American Crane Workshop

Because of a 21 % decline in breeding pairs of greater sandhill cranes (Grus canadensis tabida) on Malheur National Wildlife Refuge from 1971 to 1985, a predator control program was initiated in 1986 to enhance production. The primary cause for the decline was low recruitment of young due to high predation by ravens (Corvus corax). raccoons (Procyon lotor), and coyotes (Canis latrans), On average, predators destroyed 46% of all crane nests and 90% of the prefledged colts. Mink (Mustela vison) were added to the program in 1993 after a study …


Use Of Ultralight Aircraft For Introducing Migratory Crane Populations, Kent R. Clegg, James C. Lewis, David H. Ellis Jan 1997

Use Of Ultralight Aircraft For Introducing Migratory Crane Populations, Kent R. Clegg, James C. Lewis, David H. Ellis

Proceedings of the North American Crane Workshop

Greater sandhill cranes (Grus canadensis tabida) were used as the research surrogate for whooping cranes (Grus americana) to determine if captive-reared cranes could be led by an ultralight aircraft (UL) along a migration route and if, after release on a wintering area, they would integrate with wild cranes and migrate north in spring to their natal area without assistance. In 1995, KRC raised 15 cranes to fledging and trained them to respond to his vocal imitation of a sandhill crane brood call. Chicks learned to follow him as he walked, drove an all-terrain vehicle (ATV) , …


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 …


Use Of Cross-Fostered Whooping Cranes As Guide Birds, Roderick C. Drewien, Wendy L. Munroe, Kent R. Clegg, Wendy M. Brown Jan 1997

Use Of Cross-Fostered Whooping Cranes As Guide Birds, Roderick C. Drewien, Wendy L. Munroe, Kent R. Clegg, Wendy M. Brown

Proceedings of the North American Crane Workshop

We tested the use of wild, cross-fostered, adult whooping cranes (Grus americana) as guide birds to adopt and lead young whooping cranes on a predetermined migration route in the Rocky Mountains. We captured 3 wild adults (1 male and 1 female in 1993, 1 male in 1994) during winter at the Bosque del Apache National Wildlife Refuge (Bosque NWR), New Mexico, and moved them to captive facilities 80 kIn from Grays Lake National Wildlife Refuge (Grays Lake), Idaho, where they had originally been raised by sandhill crane (G. canadensis) foster parents. Adults were held for 6.75-7 …


Modeling The Population Dynamics Of Gulf Coast Sandhill Cranes, Douglas H. Johnson, William L. Kendall Jan 1997

Modeling The Population Dynamics Of Gulf Coast Sandhill Cranes, Douglas H. Johnson, William L. Kendall

Proceedings of the North American Crane Workshop

The Mid-continent Population of sandhill cranes (Grus canadensis) has a large geographic range. contains nearly 500,000 birds, and is hunted in much of its range. The population includes 3 subspecies; the numbers of 2 of these are uncertain, and they should be afforded protection from hunting that would be detrimental to their population. The 2 subspecies of concern tend to concentrate in the eastern part of the Great Plains during fall and spring and to winter along the Gulf Coast in Texas. This paper uses the limited information availahle ahout the Gulf Coast subpopulation in a model. We …


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. …


Microsatellite Dna Loci For Genetic Studies Of Cranes, Travis C. Glenn, Ryan S. Ojerio, Wolfgang Stephan, Michael J. Braun Jan 1997

Microsatellite Dna Loci For Genetic Studies Of Cranes, Travis C. Glenn, Ryan S. Ojerio, Wolfgang Stephan, Michael J. Braun

Proceedings of the North American Crane Workshop

MicrosateIIites are short tandem arrays of simple DNA sequences (e.g., [AC]n, where n ~ 10), which are often highly polymorphic among individuals. These repetitive elements are rapidly becoming the molecular genetic marker of choice for genetic mapping, parentage analyses, and fundamental popUlation genetics. We have isolated more than 50 microsatellite loci from the whooping crane (Grus americana). The microsatellites cloned from whooping cranes are unusually short and infrequent in comparison to other birds and especially so in comparison to mammals or reptiles. However, at least 13 of the 20 primer pairs developed amplify polymorphic loci. Paternity for …


Nesting Success And Production Of Greater Sandhill Cranes During Experimental Predator Control At Malheur National Wildlife Refuge, Oregon,1982-83, Carroll D. Littlefield, John E. Cornely Jan 1997

Nesting Success And Production Of Greater Sandhill Cranes During Experimental Predator Control At Malheur National Wildlife Refuge, Oregon,1982-83, Carroll D. Littlefield, John E. Cornely

Proceedings of the North American Crane Workshop

Greater sancfrtill cranes (Grus canadensis tabida) nest commonly on Malheur National Wildlife Refuge, Oregon, but depredations by common ravens (Corvus corax) and coyotes (Canis latrans) contributed substantially to low recruitment during the 1970's. An experimental predator removal study was initiated in 1982 to determine if nesting success and recruitment would increase if predator populations were reduced. We monitored 120 crane nests located in 2 treatment areas (ravens and coyotes removed, and only ravens removed) and 1 control area (40 nests per area). Nesting success between the 2 predator control areas differed significantly during the …


A Reintroduction Technique For Migratory Birds: Leading Canada Geese And Isolation-Reared Sandhill Cranes With Ultralight Aircraft, William A. Lishman, Tighe L. Teets, Joseph W. Duff, William J. L. Sladen, Galvin G. Shire, Kirk M. Goolsby, Wayne A. Bezner Kerr, Richard Urbanek Jan 1997

A Reintroduction Technique For Migratory Birds: Leading Canada Geese And Isolation-Reared Sandhill Cranes With Ultralight Aircraft, William A. Lishman, Tighe L. Teets, Joseph W. Duff, William J. L. Sladen, Galvin G. Shire, Kirk M. Goolsby, Wayne A. Bezner Kerr, Richard Urbanek

Proceedings of the North American Crane Workshop

No successful method for establishing self-sustaining populations of whooping cranes (Grus americana), particularly in a migration situation, has been proven. This research initiated development of a reintroduction technique using ultralight aircraft to lead cranes from a natal area along a desired route to a predetermined wintering site. Canada geese (Branta canadensis) were used in initial migration efforts. Ultralight aircraft and pilots successfully led 86 juvenile geese on 3 southbound migrations from Ontario to winter sites 640-1,312 kIn from the natal area. Of 16 1993-hatched geese that survived their first winter in Virginia and 35 1994- hatched …


An Experimental Release Of Whooping Cranes In Florida - The First Three Years, Stephen A. Nesbitt, Martin J. Folk, Marilyn G. Spalding, James A. Schmidt, Stephen T. Schwikert, Jane M. Nicolich, Marianne Wellington, James C. Lewis, Tom H. Logan Jan 1997

An Experimental Release Of Whooping Cranes In Florida - The First Three Years, Stephen A. Nesbitt, Martin J. Folk, Marilyn G. Spalding, James A. Schmidt, Stephen T. Schwikert, Jane M. Nicolich, Marianne Wellington, James C. Lewis, Tom H. Logan

Proceedings of the North American Crane Workshop

Fifty-two juvenile whooping cranes (Grus americana) were soft-released in Florida from February 1993 to April 1995. The birds were released in groups ranging in size from 5 to 14 individuals. The first-year survival rate was 0.42 for all years combined. First-year rates for each year were 0.36 for 1993, 0.32 for 1994, and 0.47 for 1995. Most mortality (62%) occurred during the first 3 months following release. The survival rate of 0.81 the second year after release was similar to that of Florida sandhill cranes (G. canadensis pratensis) (0.87). Predation by bobcats (Lynx rufus) …


Computer Simulations Of Possible Futures For Two Flocks Of Whooping Cranes, Claire M. Mirande, John R. Cannon, Kimberly Agzigian, Rozanne E. Bogart, Sarah Christiansen, Jason Dubow, A. Katya Fernandez, Dustin K. Howarth, Claudia Jones, Katherine G. Munson, Sonal I. Pandya, Gina Sedaghatkish, Kevin L. Skerl, Susan A. Stenquist, Jennifer Wheeler Jan 1997

Computer Simulations Of Possible Futures For Two Flocks Of Whooping Cranes, Claire M. Mirande, John R. Cannon, Kimberly Agzigian, Rozanne E. Bogart, Sarah Christiansen, Jason Dubow, A. Katya Fernandez, Dustin K. Howarth, Claudia Jones, Katherine G. Munson, Sonal I. Pandya, Gina Sedaghatkish, Kevin L. Skerl, Susan A. Stenquist, Jennifer Wheeler

Proceedings of the North American Crane Workshop

We conducted computer simulations using the program VORTEX (version 7) to project population sizes, growth rates, genetic diversity, and probabilities of extinction over the next 100 years for 2 flocks of whooping cranes (Grus americana), the Aransas/Wood Buffalo population and the experimental Florida population. Standard runs based on best estimates of demographic. genetic, and environmental parameter values were used as a baseline to which several alternative scenarios were compared. Results generally supported the conclusion of the earlier Population Viability Assessment (Mirande et al. 1991) that the AransaslWood Buffalo population will continue to grow steadily with less than a …


Vocalizations Of Sandhill Cranes, Stephen A. Nesbitt, Richard A. Bradley Jan 1997

Vocalizations Of Sandhill Cranes, Stephen A. Nesbitt, Richard A. Bradley

Proceedings of the North American Crane Workshop

The structure and context of 20 vocalizations given by adult or juvenile sandhill cranes (Grus canadensis) are described. Purr calls were given under various circumstances (e.g., pre-flight, feeding, aggression) and communicated information over a short distance. Flight calls, guard calls, and urtison calls were full-voiced calls that carried information over greater distances. Calls given in flight were distinguishable from other calls. Guard calls were given in several different circumstances and served multiple functions; other calls were given in very specific contexts. Beyond the basic communication of information to other cranes, vocalizations may function in mate selection and in …


Causes Of Mississippi Sandhill Crane Mortality In Captivity, 1984-95, Glenn H. Olsen, George F. Gee Jan 1997

Causes Of Mississippi Sandhill Crane Mortality In Captivity, 1984-95, Glenn H. Olsen, George F. Gee

Proceedings of the North American Crane Workshop

During 1984-95, 111 deaths were documented in the captive flock of Mississippi sandhill cranes (Grus canadensis pulla) housed at the Patuxent Wildlife Research Center. Trauma was the leading cause of death (37%), followed by infectious/parasitic diseases (25%), anatomic abnormalities (15%), and miscellaneous (8%). No positive diagnosis of cause of death was found in 19% of the necropsies. Chicks < 2 months old suffered 76 % of captive deaths. Trauma, the greatest cause of deaths of captive juveniles and adults, is likely limited to collisions in the wild. Infectious/parasitic diseases and anatomic abnormalities could affect wild chick survival at similar rates to those of captive chicks.


Harts Basin, Colorado: A Spring Migration Stopover Area For Rocky Mountain Sandhill Cranes And Whooping Cranes, Melvin K. Peterson, Roderick C. Drewien Jan 1997

Harts Basin, Colorado: A Spring Migration Stopover Area For Rocky Mountain Sandhill Cranes And Whooping Cranes, Melvin K. Peterson, Roderick C. Drewien

Proceedings of the North American Crane Workshop

Greater sandhill cranes (Grus canadensis tabida) from the Rocky Mountain Population (RMP) and whooping cranes (G. americana) reared by RMP foster parents were monitored during 1980-95 at a traditional spring migration stopover at Harts Basin in western Colorado. Counts during March and April 1986-93 showed that a mean of 10,656 RMP sandhill cranes stopped annually for 1 or more nights en route from their spring staging area in the San Luis Valley, Colorado, to summer grounds. More than 96% stopped between 11 March and 10 April. Count data indicated that > 50 % of the RMP stopped …


Avian Tuberculosis In A Whooping Crane: Treatment And Outcome, S. Bret Snyder, Michael J. Richard, Carol U. Meteyer Jan 1997

Avian Tuberculosis In A Whooping Crane: Treatment And Outcome, S. Bret Snyder, Michael J. Richard, Carol U. Meteyer

Proceedings of the North American Crane Workshop

A whooping crane (Grus americana) confirmed as suffering from Mycobacterium avium infection was treated for 1 year with daily doses of rifampin (45 mg/kg) and ethambutol (30 mg/kg) and 2 doses of M. vaccae antigen. Remission of disease occurred during therapy; however, recrudescence to active infection was suspected by 10 months after the antitubercular drugs were discontinued when the crane exhibited weight loss and had thickening of bowel wall as seen on radiographs. A second therapeutic regimen using azithromycin was then initiated (40 mg/kg fed daily) and was accompanied by a second remission within 6 weeks. After 16 …


Summary Of Sandhill Crane Hunting Seasons In North Dakota, 1968-94, David E. Sharp, John E. Cornely Jan 1997

Summary Of Sandhill Crane Hunting Seasons In North Dakota, 1968-94, David E. Sharp, John E. Cornely

Proceedings of the North American Crane Workshop

The migratory Mid-continent Population (MCP), containing 3 subspecies, is the most numerous of all sandhill crane (Grus canadensis) populations. During fall the MCP uses major staging areas in the Canadian prairie provinces and northcentral United States. In North Dakota, sport hunting of the MCP resumed in 1968, after being closed during 1916-67. The resumption and expansion of crane hunting in North Dakota during 1968-94 followed a gradual panern of implementation. Subspecies considerations, the presence of whooping cranes (G. americana), crop depredation complaints. and public reaction influenced the geographic and temporal expansion of seasons. Harvests gradually increased …