Population Biology Commons^™

Nesting Ecology Of Sandhill Cranes At Grays Lake, Idaho, Jane E. Austin, L. J. Ball, Adonia R. Henry

Proceedings of the North American Crane Workshop

We examined the nesting ecology of greater sandhill cranes (Grus canadensis tabida) at Grays Lake, Idaho during 1997-99 to detennine the effects of nest-site characteristics and land use on crane nest success. These are preliminary results from 3 years of a 4-year study. Crane nests were located in portions of the Grays Lake basin from early May through late June each year (n = 131 in 1997; n = 131 in 1998; n = 143 in 1999). Apparent nest success varied among years (54% in 1997, 71% in 1998, and 53% in 1999; overall average of 59%). We …

Translocation Of Florida Sandhill Cranes To Georgia, Wesley A. Abler, Stephen A. Nesbitt

Proceedings of the North American Crane Workshop

Wild Florida sandhill cranes (Grus canadensis pratensis) were captured in Florida during 3 years and translocated to Grand Bay Wildlife Management Area (GBWMA), Georgia, in an attempt to establish a resident population of Florida sandhill cranes in a location with suitable habitat but no known population of resident sandhill cranes. Translocated second-year subadult cranes commingled with migratory greater sandhill cranes (G. c. tabida) yet remained on GBWMA each year after the migratory birds left the area. Twenty-one of 35 released cranes were visually identified at least 5 months after release, 3 cranes more than 15 months …

Results Of The Second (1996) Experiment To Lead Cranes On Migration Behind A Motorized Ground Vehicle, David H. Ellis, Brian Clauss, Tsuyoshi Watanabe, R. Curt Mykut, Matt Shawkey, Daniel P. Mummert, Daniel T. Sprague, Catherine H. Ellis, F. Benjamin Trahan

Proceedings of the North American Crane Workshop

Fourteen greater sandhill cranes (Grus canadensis tabida) were trained to follow a specially-equipped truck and 12 were led along a ca 620-Ian route from Camp Navajo in northern Arizona to the Buenos Aires National Wildlife Refuge near the ArizonalMexico border. Ten survived the trek, 380 Ian of which were flown, although only a few cranes flew every stage of the route. Major problems during the migration were powerline collisions (ca 15, 2 fatal) and overheating (when air temperatures exceeded ca 25° C). The tenacity of the cranes in following both in 1995 and 1996 under unfavorable conditions (e.g., …

Recommendations For The Attachment Of Satellite Transmitters To Cranes, David H. Ellis, Paul W. Howey, Gary L. Krapu

Proceedings of the North American Crane Workshop

Recent advances in miniaturization of satellite transmitters have resulted in thumb-sized packages weighing less than 30 g. These are smaller than VHF radios routinely mounted on crane leg bands. With this development and with favorable signal reception results, there is no need for, and much to recommend against, the continued use of back-pack mounts. We provide details for leg-mount attachments.

Resolutions Passed By The North American Crane Working Group Eighth North American Crane Workshop, Albuquerque, New Mexico U.S.A.

Proceedings of the North American Crane Workshop

Participants of the Eighth North American Crane Workshop hereby express their thanks and appreciation to the Bosque del Apache National Wildlife Refuge for hosting this workshop, to the staff of the Sheraton Old Town Hotel, to the field trip leaders, to the staff of the Bernardo Waterfowl Management Area, and to the committees and individuals who made the workshop a success. The paper sessions were excellent, and the spirit of friendship and dedication to crane conservation among the participants was revitalizing. Special thanks go to NACWG President Scott Hereford and Bosque del Apache Biologist John Taylor for their tireless effort …

Population Genetics Of Midcontinent Sandhill Cranes, Jessica L. Petersen, Richard Bischof, Allen L. Szalanski

Proceedings of the North American Crane Workshop

The Midcontinent Sandhill Crane Population is comprised of 3 subspecies, lesser (Grus canadensis canadensis), Canadian (G. c. rowani), and greater (G. c. tabida) sandhill cranes. In conjunction with the USGS Northern Prairie Wildlife Research Center, we studied the extent of genetic variation between and within each race of the Midcontinent Sandhill Crane Population. DNA was extracted from 150 feather and dried blood samples collected from 1995-99 from sandhill cranes in the Platte River Valley, central Nebraska. Parsimony and maximwn likelihood analysis of the mtDNA D-loop sequences (ca 675 bp amplified using PCR) from 29 …

Aspects Of Reproduction And Pair Bonds In Florida Sandhill Cranes, Stephen A. Nesbitt, Martin J. Folk, Stephen T. Schwikert, James A. Schmidt

Proceedings of the North American Crane Workshop

From 1980-98 we captured and uniquely marked more than 400 Florida sandhill cranes (Grus canadensis prafensis). Age ratios of the marked population, excluding juveniles, was 66% adult and 33% subadult, and the sex ratio was 49% male and 51% female. Average clutch size for 210 nests checked from 1983-97 was 1.78 ± 0.18 (SD) and frequency of l-egg clutches varied among years. Average post-fledging brood size from 1991 to 1997 was 1.27 ± 0.17 (SD), included a 3-chick brood. Average percent ofYOlmg from 2 study areas, 1991-97 was 11.9 ± 3.23 (SD). We observed renesting up to 3 …

An Update Of The Florida Whooping Crane Release Project Through June 2000, Stephen A. Nesbitt, Martin J. Folk, Kathleen A. Sullivan, Stephen T. Schwikert, Marilyn G. Spalding

Proceedings of the North American Crane Workshop

Whooping cranes (Grus americana) reared mostly at the USGS Patuxent Wildlife Research Center (patuxent) or the International Crane Foundation (ICF) have been released in Florida in an effort to reestablish a nonmigratory population in the southeastern United States. From 1993 through spring of 2000, we released 208 cranes. Modifications to the release procedure instituted in 1995 have greatly reduced mortality from the initial release period. First year mortality has averaged 50%. A longterm drought that began after spring 1998 may have contnbuted to increased first year mortality in recent years. Most mortality has been from predation, mostly bobcat …

A Comparison Of Behavior For Two Cohorts Of Captive-Reared Greater Sandhill Cranes Released In Northern Arizona, Daniel P. Mummert, Carol L. Chambers, David H. Ellis

Proceedings of the North American Crane Workshop

To determine how the behavior of greater sandhill cranes (Grus canadensis tabida) changes according to time of year, time of day, and number of days after release, we observed the activities of 2 groups of captive-reared greater sandhill cranes at Mormon Lake, northern Arizona. The behaviors we compared were alert, loafing, sleeping, foraging, preening, locomotion, and other. We found costume-reared subadult greater sandhill cranes that were established at the study site for a year spent more time foraging and being alert towards predators than parent -reared juvenile greater sandhill cranes that were recently released from captivity. We also …

Sandhill Crane Nest And Egg Characteristics At Malheur National Wildlife Refuge, Oregon, Carroll D. Littlefield

Proceedings of the North American Crane Workshop

For the period 1969-89, greater sandhill crane (Grus canadensis tabida) nest and egg characteristics were assessed for pairs on the Malheur National Wildlife Refuge (Malheur), Oregon. Nests mostly were in broad-fruited burreed (Sparganium eurycarpum) and hardstem bulrush (Scirpus acutus) and were constructed primarily of the same vegetative species that surrounded nests. Averages for nest parameters were diameter 127 xIII cm, crown diameter 77 x 69 cm, bowl diameter 41 x 37 em, bowl depth 5.8 em, nest height 12.4 em, and water depth 25.8 cm. Nests were placed in vegetation with a mean height …

Effects Of An Early Spring Burn On Greater Sandhill Crane Nesting Success At Malheur National Wildlife Refuge, Oregon, Carroll D. Littlefield, John E. Cornely, Bradley D. Ehlers

Proceedings of the North American Crane Workshop

A 2430 ha prescribed burn was conducted on Malheur National Wildlife Refuge, Harney County, Oregon in March 1985. About 35 days later, 11 greater sandhill crane (Grus canadensis tabida) pairs nested within the burned area; 9 of these hatched. The remaining 2 clutches were destroyed by coyotes (Canis latrans). Crane hatching success was significantly higher (P = 0.01) on the burned area (81.8%) than elsewhere (38.5%). Two factors were likely responsible for the higher success rate in the burn; nests were placed in deeper water and the smaI1 mammal prey base was temporarily reduced or eliminated …

Evaluation Of The Major Histocompatibility Complex (Mhc) In Cranes: Applications To Conservation Efforts, Susan I. Jarvi, Marcia M. Miller, Ronald M. Gotol, George F. Gee, W. Elwood Briles

Proceedings of the North American Crane Workshop

Although there have been heated discussions concerning the relative importance of using Mhc diversity as a basis for selecting breeders in conservation projects, most parties agree that the genetic variability residual in an endangered species should be maintained through genetic management, if at all possible. Substantial evidence exists (particularly in birds) documenting the influences of specific Mhc haplotypes on disease outcome and also that those individuals which are heterozygous for Mhc alleles appear to have an advantage for survival over those that are homozygous. Thus, conservation of genetic variability of the Mhc is likely important for the preservation of fitness, …

Distribution, Abundance, And Reproduction Of The Cuban Sandhill Crane (Grus Canadensis Nesiotes), Xiomara Galvez Aguilera, Vicente Berovides Alvarez, Jose Rivera Rosales

Proceedings of the North American Crane Workshop

We discuss the distribution, abundance, and reproduction of the Cuban sandhill crane (Grus canadensis nesiotes). This is an overview of a 5-year study conducted by the National Organization for the Protection of Flora and Fauna of the Ministry of Agriculture for the Republic of Cuba and assisted by the International Crane Foundation and Brehm Fund. The distribution of this subspecies was determined by visiting potential sites and areas where this race has previously been reported. Nine new populations were found. This brings the total to 11 on the Isle of Cuba, 1 on Cayo Romano, and 2 on …

Interactions Of Sandhill Cranes And Whooping Cranes With Foreign Objects In Florida, Martin J. Folk, Stephen A. Nesbitt, Marilyn G. Spalding

Proceedings of the North American Crane Workshop

During studies of Florida sandhill cranes (Grus canadensis pralensis), greater sandhill cranes (G. c. tabida), and whooping cranes (G. americana) in Florida, we documented cases where these birds were in contact with human-produced objects that resulted in injury or death. We describe >40 instances in which cranes collided with powerlines or fences, became entangled in string or fishing line, or ingested foreign objects. The effect of human-produced objects on crane populations, particularly small populations, may be significant.

Isolation Effects Of Aquatic Habitat Fragmentation On Greenside (Etheostoma Blennioides) And Fantail (Etheostoma Flabellare) Darters, Rita M. Klein

Masters Theses

Aquatic habitat fragmentation is defined as the lack of connectivity between upstream and downstream populations and can occur along two gradients, the longitudinal gradient and the lateral gradient. The longitudinal gradient focuses on objects within the stream and is concerned with the disruption of stream flow, which is normally brought about by the presence of dams and bridges. Fragmentation along the lateral gradient, on the other hand, examines factors outside of the stream and is related to any loss or modification of the surrounding riparian zone.

In Illinois within the last 100 years, stream habitats have become increasingly fragmented by …