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Full-Text Articles in Ornithology
Patterns Of Food Use Of Wintering Whooping Cranes On The Texas Coast, Craig M. Westwood, Felipe Chavez-Ramirez
Patterns Of Food Use Of Wintering Whooping Cranes On The Texas Coast, Craig M. Westwood, Felipe Chavez-Ramirez
Proceedings of the North American Crane Workshop
Whooping Crane (Grus americana) fecal samples were collected from Matagorda Island National Wildlife Refuge (MINWR) during winter and fall of 1993-94 (Winter-1; n = 59), and Aransas National Wildlife Refuge (ANWR) during winter and fall of 1993-94 (n = 102) and 1994-95 (Winter-2; n = 257) to study crane diets and compare patterns of food use in these areas. Food items varied between areas, across months, and between years in both frequency and percent volume. Blue crab (Callinectes sapidus), wolfberry fruit (Lycium carolinianum), horn snail (Cerithidea pliculasa), razor clam (Tagellus plebius), …
Fecal Corticoid Monitoring In Whooping Cranes Trained To Follow Ultralight Aircraft, Barry K. Hartup, Nancy M. Czekala, Glenn H. Olsen, Julia A. Langenberg
Fecal Corticoid Monitoring In Whooping Cranes Trained To Follow Ultralight Aircraft, Barry K. Hartup, Nancy M. Czekala, Glenn H. Olsen, Julia A. Langenberg
Proceedings of the North American Crane Workshop
The use of fecal corticoid assays to measure stress in North American cranes has been limited to laboratory validation and a single field project involving reintroduced sandhill cranes (Ludders et al., 1998, 2001; Hartup et al., 2004). In 2001, we documented trends in corticoid concentrations among a cohort of ten costume-reared whooping cranes subjected to ultralight aircraft training and migration. All samples were analyzed by a validated corticosterone 125I radioimmunoassay for determination of corticoid levels. Fecal corticoid concentrations in chicks exhibited a logarithmic decline over the first 14 days after hatching (r = 0.86, p < 0.001). Fecal corticoid concentrations then stabilized at baseline levels (median 68 ng/g, range 17–186 ng/g, n = 116) during the subsequent six weeks of costume-rearing and aircraft habituation in captivity. Fecal corticoid concentrations of eight cranes increased 8-34 fold during shipment in crates to Wisconsin for field training. Increases in fecal corticoid concentrations were positively correlated with age (r = 0.81, p = 0.01), but not body weight (r = 0.44, p = 0.28) at the time of shipping. Fecal corticoid concentrations returned to baseline levels within seven days, and were sustained throughout the remainder of the training period (median 77 ng/g, range 22– 292 ng/g, n=190). Elevations in fecal corticoid concentrations were observed one (p = 0.035) and four days (p = 0.003) following physical examination and placement of leg bands compared to three days prior to the procedures (median 176 ng/g, range 116 – 553 ng/g, n = 19). Fecal corticoid concentrations decreased to pre-procedure levels within seven days. Fecal corticoid concentrations and variation during the 50 day migration period were similar to training levels in Wisconsin, except for a one day increase observed following a violent storm and escape from the temporary holding pen the preceding night (median 243 ng/g, range 228 – 280 ng/g, n = 7). There was an overall decline in fecal corticoid concentrations from the cranes during the migration (r = 0.42, p < 0.001). Acute stressors such as capture and restraint and severe storms were associated with stress responses by the cranes that varied in accordance with lasting physical or psychological stimuli. The overall process of costume-rearing, ultralight aircraft habituation, training and artificial migration was not associated with elevations in fecal corticoid concentrations suggestive of chronic stress.
Patterns Of Habitat Use By Whooping Cranes During Migration: Summary From 1977–1999 Site Evaluation Data, Jane E. Austin, Amy L. Richert
Patterns Of Habitat Use By Whooping Cranes During Migration: Summary From 1977–1999 Site Evaluation Data, Jane E. Austin, Amy L. Richert
Proceedings of the North American Crane Workshop
We used site evaluation data collected during 1977–1999 to examine patterns of habitat use by whooping cranes (Grus americana) during migration through the United States portion of the Wood Buffalo–Aransas flyway. We examined characteristics of 3 types of stopover habitats: 1) roost sites (n = 141 records), 2) feeding sites (n = 306), and 3) dual-use sites (i.e., where observer recorded cranes as using a site for both roosting and feeding (n = 248). Results in spring were influenced by the large number of records from Nebraska (> 67% of spring records) and in fall by frequent observations …
Philopatry And Dispersal In Whooping Cranes, Brian W. Johns, J. Paul Goossen, Ernie Kuyt, Lea Craig-Moore
Philopatry And Dispersal In Whooping Cranes, Brian W. Johns, J. Paul Goossen, Ernie Kuyt, Lea Craig-Moore
Proceedings of the North American Crane Workshop
The natal and breeding dispersal of endangered whooping cranes (Grus americana) was investigated using information collected between 1978-2002 on the nesting grounds in and near Wood Buffalo National Park, Alberta-Northwest Territories. A minimum of 77% of the juveniles color-banded near their natal sites returned to the breeding grounds. Sex-biased natal dispersal was not observed. At least 76% of first-time breeders nested within 20 km of their natal site. Pioneering was rare and most cranes nested on the primary nesting areas adjacent to the Sass and Klewi rivers. The mechanism enhancing natal philopatry is probably related to learning the …
Techniques Employed To Capture Whooping Cranes In Central Florida, Martin J. Folk, Stephen A. Nesbitt, Stephen T. Schwikert, James A. Schmidt, Kathleen A. Sullivan, Thomas J. Miller, Stephen B. Baynes, Jeannette M. Parker
Techniques Employed To Capture Whooping Cranes In Central Florida, Martin J. Folk, Stephen A. Nesbitt, Stephen T. Schwikert, James A. Schmidt, Kathleen A. Sullivan, Thomas J. Miller, Stephen B. Baynes, Jeannette M. Parker
Proceedings of the North American Crane Workshop
During the course of re-introduction of a non-migratory flock of whooping cranes to Florida (1993-2002) a variety of techniques were used to capture 105 free-living birds. The most commonly used technique was hand-capture from a feed trough blind (45 birds). Whooping cranes were also captured by use of snares, several types of nets, and by hand. All techniques were relatively safe and posed little risk to the birds, a primary concern when dealing with rare birds. We found it useful to employ a diversity of techniques because some methods work better than others under differing circumstances. Capturing whooping cranes for …
Head Stabilization In Whooping Cranes, Matthew R. Kinloch, Thomas W. Cronin, Glenn H. Olsen
Head Stabilization In Whooping Cranes, Matthew R. Kinloch, Thomas W. Cronin, Glenn H. Olsen
Proceedings of the North American Crane Workshop
The whooping crane (Grus americana) is the tallest bird in North America, yet not much is known about its visual ecology. How these birds overcome their unusual height to identify, locate, track, and capture prey items is not well understood. There have been many studies on head and eye stabilization in large wading birds (herons and egrets), but the pattern of head movement and stabilization during foraging is unclear. Patterns of head movement and stabilization during walking were examined in whooping cranes at Patuxent Wildlife Research Center, Laurel, Maryland USA. Four whooping cranes (1 male and 3 females) …
Reintroduction Techniques: Post-Release Performance Of Sandhill Cranes (1) Released Into Wild Flocks And (2) Led On Migration By Ultralight Aircraft, Richard P. Urbanek, Joseph W. Duff, Scott R. Swengel, Lara E. A. Fondow
Reintroduction Techniques: Post-Release Performance Of Sandhill Cranes (1) Released Into Wild Flocks And (2) Led On Migration By Ultralight Aircraft, Richard P. Urbanek, Joseph W. Duff, Scott R. Swengel, Lara E. A. Fondow
Proceedings of the North American Crane Workshop
Two methods of reintroducing a migratory population of whooping cranes (Grus americana) were tested with costume/ isolation-reared juvenile greater sandhill cranes (G. canadensis tabida): (1) release into wild flocks during autumn staging and (2) leading on autumn migration by ultralight aircraft. Birds in the first group were released singly, and all integrated quickly into the wild flocks and adopted similar behavioral patterns. Birds in the second group were led to winter on an inland site on the Gulf Coast of Florida. Most of the birds led by ultralight aircraft remained in their juvenile cohort through the …
Natural Fertility In Whooping Cranes And Mississippi Sandhill Cranes At Patuxent Wildlife Research Center, Jane M. Nicolich, George F. Gee, David H. Ellis, Scott G. Hereford
Natural Fertility In Whooping Cranes And Mississippi Sandhill Cranes At Patuxent Wildlife Research Center, Jane M. Nicolich, George F. Gee, David H. Ellis, Scott G. Hereford
Proceedings of the North American Crane Workshop
The first fertile whooping crane (Grus americana; WC) egg produced through natural breeding at Patuxent Wildlife Research Center (patuxent) was laid in 1991. Prior to that time, all fertile whooping crane eggs were the result of artificial insemination. Since 1991, eight different whooping crane pairs at Patuxent have produced fertile eggs through natural breeding. Mean fertility averages over years for each pair range from 40% to 93%. Fertility rates for each pair also vary greatly between years, from 0% to 100%, but the causes of the variance are unknown. Experiences with natural fertility in Mississippi sandhill cranes (G …
Platte River Cooperative Agreement And Proposed Program: Efforts To Protect, Restore, And Manage Habitat For Whooping Cranes, Least Terns, And Piping Plovers, Clayton Derby, Dale Strickland
Platte River Cooperative Agreement And Proposed Program: Efforts To Protect, Restore, And Manage Habitat For Whooping Cranes, Least Terns, And Piping Plovers, Clayton Derby, Dale Strickland
Proceedings of the North American Crane Workshop
On 1 July 1997 the states of Nebraska, Wyoming, and Colorado and the U.S. Department of the Interior signed the "Cooperative Agreement for Platte River Research and Other Efforts Relating to Endangered Species Habitats Along the Central Platte River, Nebraska" (Cooperative Agreement). In the Cooperative Agreement, the four parties set forth a "Proposed Platte River Recovery Implementation Program" (Program). The proposed incremental Program uses adaptive management to provide benefits to whooping cranes (Grus americana), least terns (Sterna albifrons), and piping plovers (Charadrius melodus). The proposed Program will also test the assumption that it is possible …
Whooping Crane Egg Management: Options And Consequences, David H. Ellis, George F. Gee
Whooping Crane Egg Management: Options And Consequences, David H. Ellis, George F. Gee
Proceedings of the North American Crane Workshop
Eggs to build captive whooping crane (Grus americana) flocks and most eggs for reintroduction experiments have come from second viable eggs in 2-egg clutches in Canada. Four years ago, egg removal ceased. Based on reproductive rates for years when second eggs were removed and for years when eggs were not removed, we project numbers of young fledging in the wild and in captivity for the 2 most likely egg-management strategies. From existing data sets, we find that reproductive performance was, on average, better during the era of routine removal of the second viable eggs than when no manipulation …
Ingested Metal In Whooping Cranes: An Endoscopic Technique For Removal And Implications For The Release Program, Glenn H. Olsen, Michael Wise
Ingested Metal In Whooping Cranes: An Endoscopic Technique For Removal And Implications For The Release Program, Glenn H. Olsen, Michael Wise
Proceedings of the North American Crane Workshop
Since 1993 when the whooping crane (Grus americana) release program in Florida started, 21 whooping cranes at the USGS Patuxent Wildlife Research Center (patuxent) have been diagnosed with gastrointestinal foreign bodies (primarily metal objects). A technique for safely removing these objects has been developed. The technique uses a flexible gastric endoscope to enter the proventriculus or ventriculus, and a snare or forceps passed down a channel of the endoscope to retrieve the foreign bodies. The technique is very successful, with the whooping crane usually back to its pen the next day. The longterm survival of the whooping cranes …
Developing A Migratory Whooping Crane Flock, Robert H. Horwich
Developing A Migratory Whooping Crane Flock, Robert H. Horwich
Proceedings of the North American Crane Workshop
Research on crane reintroductions within the last 15 years has produced information necessary to effect a successful reintroduction of a migratory whooping crane (Grus americana) flock. There are 4 main problems to solve for such a reintroduction: (1) inducing a high survival rate of the reintroduced cranes, (2) encouraging normal reproduction with conspecifics, (3) teaching the reintroduced cranes the migration route, and (4) inducing fear of humans in the reintroduced cranes. Use of an isolation-rearing method by the author, using puppets, sounds, and costumes, has led to a consistent, over 80%, survival rate for the reintroduced young cranes …
Multiple Spatial Scale Analysis Of Whooping Crane Habitat In Nebraska, Amy L. Richert, Kevin E. Church
Multiple Spatial Scale Analysis Of Whooping Crane Habitat In Nebraska, Amy L. Richert, Kevin E. Church
Proceedings of the North American Crane Workshop
Geographic Information System (GIS) and remote sensing technologies were used to evaluate whooping crane stopover habitat in Nebraska. The goal of the research was to investigate habitat selection at multiple spatial scales. The GIS database consisted of all confirmed whooping crane sightings reported in Nebraska from 1975-1996 and land cover information delineated from color infrared aerial photographs and Landsat Thematic Mapper data. Results suggest that whooping cranes select roost habitat by recognizing site-level and landscape-scale land cover composition. Wetland is the most strongly selected habitat type at all spatial scales examined. This presentation emphasizes methods used to analyze habitat selection …
Whooping Cranes Breeding At White Lake, Louisiana, 1939: Observations By John J. Lynch, U. S. Bureau Of Biological Survey, Roderick C. Drewien, John Tautin, Mary Lynch Courville, Gay M. Gomez
Whooping Cranes Breeding At White Lake, Louisiana, 1939: Observations By John J. Lynch, U. S. Bureau Of Biological Survey, Roderick C. Drewien, John Tautin, Mary Lynch Courville, Gay M. Gomez
Proceedings of the North American Crane Workshop
On 15 May 1939, Jo1m J. Lynch of the U.S. Bureau of Biological Survey located l3 whooping cranes (Grus americana), including 2 prefledged young, during an aerial survey near White Lake in southwestern Louisiana. His observation was the last historic record of whooping cranes breeding in the wild in the United States, and it confinned the presence of a nonmigratory breeding population along the Gulf Coast. While reviewing old U.S. Fish and Wildlife Service files at the National Archives in 1999, we located Lynch's original 1939 field note, 2 letters, 5 photographs, and a draft manuscript describing the …
Increased Egg Conservation: Is It Essential For Recovery Of Whooping Cranes In The Aransas/Wood Buffalo Population?, James C. Lewis
Increased Egg Conservation: Is It Essential For Recovery Of Whooping Cranes In The Aransas/Wood Buffalo Population?, James C. Lewis
Proceedings of the North American Crane Workshop
The whooping crane (Grus americana) is in a race for survival against adversities (genetic, demographic, and environmental) that are only partially understood. There is increasing evidence of genetic problems (drift, inbreeding, and loss of heterozygosity) in the captive population that likely also exist in the wild Aransas-Wood Buffalo Population (A WP), a consequence of the 1940s population bottleneck. Small populations are vulnerable to extinction through catastrophic events and random changes in productivity or survival. Negative environmental effects faced by whooping cranes include upstream diversion which diminish freshwater (nutrient) inflow into Texas wintering habitats, and expanding human activities along …
Continuing Studies Of Ultralight Aircraft Applications For Introducing Migratory Populations Of Endangered Cranes, Kent R. Clegg, James C. Lewis
Continuing Studies Of Ultralight Aircraft Applications For Introducing Migratory Populations Of Endangered Cranes, Kent R. Clegg, James C. Lewis
Proceedings of the North American Crane Workshop
This research tested whether captive-reared cranes led by an ultralight aircraft (UL) along a migration route, would, after release on a wintering area, integrate with wild cranes and migrate in spring to their natal area without human assistance. This was the historical first motorized migration involving an endangered species. In 1997, whooping cranes (Grus americana) and greater sandhill cranes (Grus canadensis tabida) were group-reared in species-specific pens and 80% fledged. Beginning 13 October, 4 whooping cranes and 8 sandhill cranes were led along a 1, 133-km migration route from Grace, Idaho, to Bosque del Apache National …
Promoting Wildness In Sandhill Cranes Conditioned To Follow An Ultralight Aircraft, Joseph W. Duff, William A. Lishman, Dewitt A. Clark, George F. Gee, Daniel T. Sprague, David H. Ellis
Promoting Wildness In Sandhill Cranes Conditioned To Follow An Ultralight Aircraft, Joseph W. Duff, William A. Lishman, Dewitt A. Clark, George F. Gee, Daniel T. Sprague, David H. Ellis
Proceedings of the North American Crane Workshop
During the 1998 field season, we developed and tested a new protocol to teach sandhill cranes (Grus canadensis) to follow ultralight aircraft yet avoid humans. Although successful in teaching the cranes a migration route, our previous migration (1997) resulted in birds that were overly tame and sought association with humans. For this study, 16 sandhill cranes were costume-reared at USGS Patuxent Wildlife Research Center and transported to Ontario shortly before fledging. After the birds learned to follow the aircraft, 14 were transported to an isolated wintering site in South Carolina, 1300 km south of the training area. Twelve …
Water Conditioning And Whooping Crane Survival After Release In Florida, George F. Gee, Jane M. Nicolich, Stephen A. Nesbitt, Jeff S. Hatfield, David H. Ellis, Glenn H. Olsen
Water Conditioning And Whooping Crane Survival After Release In Florida, George F. Gee, Jane M. Nicolich, Stephen A. Nesbitt, Jeff S. Hatfield, David H. Ellis, Glenn H. Olsen
Proceedings of the North American Crane Workshop
About 50% of the whooping cranes (Grus americana) released in Florida die within the first year of release. Most of these deaths and those in subsequent years result from bobcat (Lynx rufus) predation. Choosing release sites in open marshes away from bobcat habitat has improved survival. We hypothesized that exposure to ponds (water conditioning) at the rearing site would encourage birds to roost in deeper water marshes after release and such exposure would thereby reduce bobcat predation. In this study, we moved young birds (ca 50 days of age) to netted pens with large (I5-m diameter), deep (30--60 …
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
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 …
Tracking Sandhill Crane Migration From Saskatchewan To The Gulf Coast, Dale G. Hjertaas, David H. Ellis, Brian W. Johns, Stacie L. Moon
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 …
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
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 …
Woody Vegetation Expansion And Continuing Declines In Open Channel Habitat On The Platte River In Nebraska, Paul J. Currier
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 …
Results Of An Experiment To Lead Cranes On Migration Behind Motorized Ground Vehicles, David H. Ellis, Brian Clauss, Tsuyoshi Watanabe, R. Curt Mykut, Matthew Kinloch, Catherine H. Ellis
Results Of An Experiment To Lead Cranes On Migration Behind Motorized Ground Vehicles, David H. Ellis, Brian Clauss, Tsuyoshi Watanabe, R. Curt Mykut, Matthew Kinloch, Catherine H. Ellis
Proceedings of the North American Crane Workshop
Ten greater sandhill cranes (Grus canadensis tabida) , trained to enter and ride in a specially-equipped truck, were transported at ca 80 days of age from their rearing site at Patuxent Wildlife Research Center (patuxent), Maryland, to a reintroduction site located within the species' former breeding range in northern Arizona. After 5 additional weeks of training, these juvenile cranes were led south ca 600 km to a wintering area on the Arizona/Mexico border. Nine of the 10 survived the trek, 495 km of which were flown, although only a few cranes flew every stage of the route. Their …
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
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 …
Use Of Ultralight Aircraft For Introducing Migratory Crane Populations, Kent R. Clegg, James C. Lewis, David H. Ellis
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) , …
Food And Energy Intake Rates Of Wintering Whooping Cranes Foraging On Two Selected Food Items, Felipe Chavez-Ramirez, Jay T. Nelson, R. Douglas Slack
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 …
Contaminants In Habitat, Tissues, And Eggs Of Whooping Cranes, James C. Lewis, Roderick C. Drewien, Ernie Kuyt, Charles Sanchez Jr.
Contaminants In Habitat, Tissues, And Eggs Of Whooping Cranes, James C. Lewis, Roderick C. Drewien, Ernie Kuyt, Charles Sanchez Jr.
Proceedings of the North American Crane Workshop
Sampling of contaminants in the principal habitat areas of whooping cranes (Grus americana) of both the Rocky Mountain and the Aransas/Wood Buffalo National Park whooping crane populations began in the mid-1980's. Contaminants in eggs and tissues of whooping cranes were sampled opportunistically since the 1960's. Chlorinated hydrocarbons existed in low levels in the environment. Some trace elements including aluminum, arsenic, cadmium, chromium, copper. mercury, selenium, and zinc are of sufficient abundance to justify continued monitoring. Declines over time in residues of DDT and mercury in tissues and eggs reflected the prohibition in use of these as pesticides or …
Capturing Whooping Cranes And Sandhill Cranes By Night-Lighting, Roderick C. Drewien, Kent R. Clegg
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 …
Marking Power Lines To Reduce Avian Collision Mortality In The San Luis Valley, Colorado, Wendy M. Brown, Roderick C. Drewien
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 …
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
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 …