Open Access. Powered by Scholars. Published by Universities.®

Population Biology Commons™

Open Access. Powered by Scholars. Published by Universities.®

Behavior and Ethology

PDF

University of Nebraska - Lincoln

Keyword
Publication Year
Publication
Publication Type

Articles 421 - 450 of 450

Full-Text Articles in Population Biology

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 …

Go to article

Habitat Use By Florida Sandhill Cranes In The Okefenokee Swamp, Georgia, Alan J. Bennett Jan 1992

Habitat Use By Florida Sandhill Cranes In The Okefenokee Swamp, Georgia, Alan J. Bennett

Proceedings of the North American Crane Workshop

Habitat selection by Florida sandhill cranes (Grus canadensis pratensis) in the Okefenokee Swamp was studied 1985-87. Wetland habitats were used exclusively. Herbaceous emergent marsh was the only habitat selected throughout the year. Although composing only 12.6% of the Swamp, such marsh received 54.8% use. Use of macrophyte emergent marsh (aquatic bed) peaked during summer and averaged 24.2% throughout the year. Shrub-scrub marsh, used for nesting, received 14.2% use. Habitat selection by adults and subadults (1-3 year-olds) was similar. Significant differences occurred only in spring when adults utilized Carex sp. and shrub-scrub marsh for nesting. Water depths in the …

Go to article

Territorial Behavior Of Florida Sandhill Cranes In The Okefenokee Swamp, Laurel A. Bennett, Alan J. Bennett Jan 1992

Territorial Behavior Of Florida Sandhill Cranes In The Okefenokee Swamp, Laurel A. Bennett, Alan J. Bennett

Proceedings of the North American Crane Workshop

Intraspecific and territorial interactions of adult Florida sandhill cranes (Grus canadensis pratensis) were studied in the Okefenokee Swamp, Georgia 1985-87. Adult pairs occupied exclusive and defended territories year round. We did not observe social behavior or flocking by adult cranes. Reproductive success did not influence the fidelity of pairs to their territories or aggressiveness toward other cranes. Females that lost mates retained their territories and eventually re-paired. Territorality was most intense during fall and winter and may have been necessary to maintain feeding areas. Habitat conditions in the Okefenokee Swamp may dictate territorality, not sociality, as a strategy …

Go to article

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 …

Go to article

A Microcomputer Data Base For Managing Whooping Crane Observation Records, Duane A. Asherin, David B. Hamilton, Wendy M. Brown, Roderick C. Drewien Jan 1992

A Microcomputer Data Base For Managing Whooping Crane Observation Records, Duane A. Asherin, David B. Hamilton, Wendy M. Brown, Roderick C. Drewien

Proceedings of the North American Crane Workshop

A database called WHOOPER contains whooping crane (Grus americana) observations for the Rocky Mountain foster-parent population and currently consists of 1,438 observations covering the period 1975-1987. The dBase III Plus database management system for microcomputers is used for the application. This description of the data base and its capabilities updates the prototype database described in the 1985 Crane Workshop.

Go to article

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. …

Go to article

Unobstructed Visibility At Whooping Crane Roost Sites On The Platte River, Nebraska, Craig A. Faanes Jan 1992

Unobstructed Visibility At Whooping Crane Roost Sites On The Platte River, Nebraska, Craig A. Faanes

Proceedings of the North American Crane Workshop

Unobstructed visibility is an important component of whooping crane (Grus americana) roosting habitat. Recent habitat modeling efforts suggest that unobstructed horizontal visibility is suitable at a minimum of 335 m. Unobstructed upstream and downstream visibility is also an important part of whooping crane roosting habitat, but quantification of that parameter has not been reported previously, or incorporated into species models. Data from the Platte River suggest that a minimum of 732 m of unobstructed upstream and downstream visibility is needed at whooping crane roost sites.

Go to article

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.

Go to article

Crane Propagation At Miami Metrozoo, 1983-1987, Carol G. Hesch Jan 1992

Crane Propagation At Miami Metrozoo, 1983-1987, Carol G. Hesch

Proceedings of the North American Crane Workshop

Five species of cranes are bred at Miami Metrozoo. Few health problems have been encountered in raising a large number of chicks. Rearing cranes in close confinement, with limited resources, requires sound management and careful observation.

Go to article

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 …

Go to article

Whooping Cranes At The San Antonio Zoo, Jacqueline A. Lauver Jan 1992

Whooping Cranes At The San Antonio Zoo, Jacqueline A. Lauver

Proceedings of the North American Crane Workshop

Since April, 1956, when an injured whooping crane (Grus americana) was received for rehabilitation, the San Antonio Zoo has maintained these birds in the collection and is 1 of only 2 zoos to have raised them. The zoo's management efforts, combined with favorable climatic cbnditions and water sources have contributed to a successful breeding program. The whooping crane is 1 of 7 crane species successfully bred, and 1 of 8 crane species currently in the collection.

Go to article

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. …

Go to article

An Evaluation Of Three Areas For Potential Populatons Of Whooping Cranes, Janet L. Mcmillen, Stephen A. Nesbitt, Mary A. Bishop, Alan J. Bennett, Laurel A. Bennett Jan 1992

An Evaluation Of Three Areas For Potential Populatons Of Whooping Cranes, Janet L. Mcmillen, Stephen A. Nesbitt, Mary A. Bishop, Alan J. Bennett, Laurel A. Bennett

Proceedings of the North American Crane Workshop

Sandhill crane (Grus canadensis) populations were evaluated on the Seney NWR, Michigan, the Okefenokee Swamp, Georgia, and in southcentral Florida to evaluate their suitability to support introduced whooping cranes (G. americana). This paper compares data collected at these sites and additional data collected in northcentral Florida. The length of the egg-laying period varied from 4.5 months in central Florida to 1 month at Seney, but egg-laying ceased at all sites from mid-May to early June. Mean clutch sizes were similar 0.7-1.9). Renesting ranged from 79% in northcentral Florida to <=5% at Seney. These dates and values are consistent with nesting successes that ranged from 48% in northcentral Florida to 80% at Seney. Average annual recruitment, 12.3 juveniles/lOa adults, was highest on the Kissimmee Prairie in southcentral Florida. Average annual horne range size for the non-migratory populations were 1 km2 on the Okefenokee and 6.6 km2 on the Kissimmee. Nesting season horne range sizes ranged from 0.5 km2 on the Okefenokee to 1.8 km2 at Seney. All candidate populations successfully satisfied most of the guidelines for potential whooping crane populations as established by the Whooping Crane Recovery Team. Once reintroduction techniques have been refined, any or all of the study sites have the capacity to accommodate a flock of whooping cranes commensurate with Whooping Crane Recovery Team recommendations.

Go to article

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 …

Go to article

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.

Go to article

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 …

Go to article

Whooping Crane Habitat Alteration Analysis At Aransas National Wildlife Refuge, Texas, C. Lee Sherrod, Richard Medina Jan 1992

Whooping Crane Habitat Alteration Analysis At Aransas National Wildlife Refuge, Texas, C. Lee Sherrod, Richard Medina

Proceedings of the North American Crane Workshop

Aquatic, wetland, and upland habitat changes were quantified within the approximate critical habitat of the endangered whooping crane (Grus americana) along the Gulf Intracoastal Waterway (GIWW) through Aransas National Wildlife Refuge and San Antonio, Bay, Texas. Study procedures employed comparative analysis of pre-GIWW (1930) and present (1986) aerial photography to provide a basis for the assessment of positive and negative impacts of the construction, operation and maintenance of the GIWW, principally on the whooping crane, but also on biota in general. Thirteen habitat mapping categories were utilized to describe an approximately 1,830 m wide corridor along the GIWW …

Go to article

Nesting Of Greater Sandhill Cranes On Seney National Wildlife Refuge, Richard P. Urbanek, Theodore A. Bookhout Jan 1992

Nesting Of Greater Sandhill Cranes On Seney National Wildlife Refuge, Richard P. Urbanek, Theodore A. Bookhout

Proceedings of the North American Crane Workshop

During 1987, 59 nests of 57 pairs of greater sandhill cranes (Grus canadensis tabida) were located, mainly from the air, on or near the Seney National Wildlife Refuge, Michigan, and 52 nests were ground-checked. Nests were in available palustrine classes without tree canopies. Only 19% were in Sphagnum bogs, in which most nests from other areas of the Upper Peninsula have been found. Cattail (Typha latifolia) marshes, most prevalent in the managed area of the refuge, contabed 44% of the nests, and sedge (Carex spp.) marshes accounted for 37%. Important co-dominant plant species were …

Go to article

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.

Go to article

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 …

Go to article

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 …

Go to article

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 …

Go to article

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 …

Go to article

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). …

Go to article

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.

Go to article

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 …

Go to article

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.

Go to article

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.

Go to article

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 …

Go to article

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, …

Go to article

First Prev