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Full-Text Articles in Animal Sciences

Sandhill Crane Surveys In The Northern Interior Highlands Of Mexico, Roderick C. Drewien, Wendy M. Brown, Elwood G. Bizeau Jan 1992

Sandhill Crane Surveys In The Northern Interior Highlands Of Mexico, Roderick C. Drewien, Wendy M. Brown, Elwood G. Bizeau

Proceedings of the North American Crane Workshop

Most sandhill cranes (Grus canadensis) wintering in Mexico are found in the northern Interior Highlands of Chihuahua. We surveyed sandhill cranes in the states of Chihuahua and occasionally Durango, Mexico, in winters 1972-90. The population averaged 23,106 (SD = 10,369) in 11 counts at 5-6 areas in Chihuahua. Laguna de Babicora, the most important wetland for cranes wintering in Mexico, had the largest numbers (X = 16,012), followed by Ascension (x = 2,405) and Laguna de los Mexicanos (x = 1,468). All 3 migratory subspecies were present. The lesser subspecies (G. c. canadensis) comprised 85.7% of …


Contaminants In Habitat, Tissues, And Eggs Of Whooping Cranes, James C. Lewis, Roderick C. Drewien, Ernie Kuyt, Charles Sanchez Jr. Jan 1992

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 …


Using National Wetlands Inventory Maps To Quantify Whooping Crane Stopover Habitat In Oklahoma, Dale W. Stahlecker Jan 1992

Using National Wetlands Inventory Maps To Quantify Whooping Crane Stopover Habitat In Oklahoma, Dale W. Stahlecker

Proceedings of the North American Crane Workshop

Three stratified random samples of the 416 National Wetland Inventory (NWI) maps within the western Oklahoma portion of the Wood Buffalo-Aransas whooping crane (Grus americana) migration corridor were used to evaluate the availability of wetland roost sites. Wetlands were eliminated as potential roosts if visibility was obscured by vegetation or slope, or if certain human activities occurred within 100-800 m. Thirty percent of all wetlands >0.04 ha passed map review, but only 7% passed when ground truthed. NWI map review was a poor predictor of suitability (33 % correct) but a good predictor of unsuitability (97 % correct). …


Behavior Of Whooping Cranes During Initiation Of Migration, Thomas V. Stehn Jan 1992

Behavior Of Whooping Cranes During Initiation Of Migration, Thomas V. Stehn

Proceedings of the North American Crane Workshop

Whooping cranes (Grus americana) observed immediately before the initiation of migratory flights exhibited increased alertness, wing ruffling, and head tilting. Seven observations at Aransas National Wildlife Refuge (NWR), Texas, indicate that the departure of 1 group of whooping cranes may influence other nearby cranes to start migration, even though later departing groups may fly separately.


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 …


Preliminary Identification Of Whooping Crane Staging Areas In Prairie Canada, Brian W. Johns Jan 1992

Preliminary Identification Of Whooping Crane Staging Areas In Prairie Canada, Brian W. Johns

Proceedings of the North American Crane Workshop

For 60 years a passive program has been in effect to monitor the migration of whooping cranes (Grus americana) through Saskatchewan, and currently the Canadian Wildlife Service coordinates a triprovincial reporting network and operates a telephone Hot Line to receive reports of sightings of migrating cranes. Analyses of historical data reported through those efforts have identified the chronology of migration, the migration corridor through Canada, and major staging/ stopover areas in Saskatchewan. Investigations are continuing to identify specific roost sites, feeding areas and the availability of suitable habitat within the staging/ stopover area.


Relationship Of Channel Maintenance Flows To Whooping Crane Use Of The Platte River, Craig A. Faanes, David B. Bowman Jan 1992

Relationship Of Channel Maintenance Flows To Whooping Crane Use Of The Platte River, Craig A. Faanes, David B. Bowman

Proceedings of the North American Crane Workshop

Periodic high flows in the Platte River are necessary to scour vegetation and redistribute sediment in the stream channel. Peak and mean annual flows have been reduced by as much as 70% from pre-development times, but channel maintenance flows still occur, although at a much reduced frequency and magnitude of occurrence. Use of the Platte River by migrant whooping cranes (Grus americana) in recent years appears to be related to the recent occurrence of flows in excess of 8,000 cfs for 5 or more consecutive days.


Lead Poisoning In A Whooping Crane, S. Bret Synder, Michael J. Richard, John P. Thilsted, Roderick C. Drewien, James C. Lewis Jan 1992

Lead Poisoning In A Whooping Crane, S. Bret Synder, Michael J. Richard, John P. Thilsted, Roderick C. Drewien, James C. Lewis

Proceedings of the North American Crane Workshop

The first known incident of lead poisoning in a whooping crane (Grus americana) occurred as the affected bird completed its second migration from Grays Lake National Wildlife Refuge (NWR), Idaho to Bosque del Apache NWR, New Mexico. It fell ill about 4 1/2 weeks after reaching the winter site and was captured. The bird exhibited signs of anorexia and starvation, weakness with drooped wings, greenish watery diarrhea and an unusual gaping of the mouth with abnormal swallowing motions. Blood showed marked polychromasia (>50%) and reticulocytosis (>80%) of RBC's. Serum chemistry values were not diagnostic. A radiograph …


The Study Of Relatedness And Genetic Diversity In Cranes, George F. Gee, Herbert C. Dessauer, Jonathan Longmire, W. Elwood Briles, Raymond C. Simon Jan 1992

The Study Of Relatedness And Genetic Diversity In Cranes, George F. Gee, Herbert C. Dessauer, Jonathan Longmire, W. Elwood Briles, Raymond C. Simon

Proceedings of the North American Crane Workshop

The U.S. Fish and Wildlife Service (Service) is responsible for recovery of endangered species in the wild and, when necessary, maintenance in captivity. These programs provide an immediate measure of insurance against extinction. A prerequisite inherent in all of these programs is the preservation of enough genetic diversity to maintain a viable population and to maintain the capacity of the population to respond to change. Measures of genetic diversity examine polymorphic genes that are not influenced by selection pressures. Examples of these techniques and those used to determine relatedness are discussed. Studies of genetic diversity, electrophoresis of blood proteins, relatedness, …