Master of Science (MS)


Biomedical and Veterinary Medical Sciences - Veterinary Clinical Sciences

Document Type



The Mississippi Sandhill Crane (Grus canadensis pulla), the most endangered North American crane, is considered critically endangered and is protected by Federal and State law. Substantial funding has established the Mississippi Sandhill Crane National Wildlife Refuge in Southern Mississippi and an artificial insemination / breeding facility at the Audubon Center for Research of Endangered Species in New Orleans, Louisiana to promote species recovery. In spite of extensive time, labor, and money invested in captive propagation, juvenile Mississippi Sandhill Cranes suffer substantial mortality due to predation by bobcats (Lynx rufus), coyotes (Canis latrans) and red tailed hawks (Buteo jamaicensis) upon reintroduction to the refuge. Studies have shown decreased avian mortality in reintroduction programs incorporating antipredator conditioning. Appropriate antipredator behaviors are likely innate in cranes, however the object at which to direct these behaviors may require social learning in lieu of the normally long period of parental care known in this species. An antipredator conditioning program was conducted prior to release for 2 years in juvenile Mississippi Sandhill Cranes using live tame predators and conspecific presence to teach predator recognition and appropriate responses. Death of juvenile cranes upon reintroduction to the refuge due to predation has not occurred since the inception of the program. However, factors such as an increase in predator control or differing weather conditions may have contributed to these results. Behavioral results strongly suggest that the presence of adult cranes during antipredator conditioning of subadult cranes is of benefit. With the presence of an adult pair of cranes (models), subadult cranes show significantly more vigilance in the form of the tall alert behavior. Contact call and guard call occurrence were associated with age, however appropriate vocal response to predator presence occurred regardless of whether a model was present. No cranes were harmed during antipredator conditioning procedures, and time and money expenditures were minimal. Antipredator conditioning programs for cranes can be relatively simple and inexpensive with minimal risk to participants. We strongly recommend similar procedures be incorporated into other avian endangered species reintroduction programs.



Document Availability at the Time of Submission

Release the entire work immediately for access worldwide.

Committee Chair

Thomas N. Tully, Jr.