Meeting the Challenge of Preserving Endangered Species

The grasslands of the western Great Plains are the natural habitat of black-footed ferrets and their prey, prairie dogs.

The National Zoo's Black-Footed Ferret Reproduction Project studies the biology of the black-footed ferret to enhance reproduction, maintain genetic diversity, and provide animals for reintroduction to the western Great Plains.

Reintroduction and Pre-Release Training

The return of black-footed ferrets to the plains of the American West began in 1991. Research revealed that survival rates were higher among ferrets that were exposed to outdoor burrows with prairie dogs before reintroduction. The National Zoo's Smithsonian Conservation Biology Institute (SCBI) created “pre-release conditioning pens” with prairie dog burrow systems. Each year, animals born at SCBI in Front Royal, Virginia (SCBI-FR) are given access to these burrows to increase the chances of their survival after release. Ferrets born and conditioned at SCBI-FR have been released in Wyoming, Arizona, Utah, South Dakota, Montana, and Mexico.

Meeting the Challenge

Our studies of black-footed ferrets are helping to save one of North America’s most endangered species and return it to nature, but funding for research has been scarce.

Current Projects in Need of Support

• Improving semen freezing methods and expanding the Genome Resource Bank to increase artificial insemination efficiency.
• Understanding reproductive success in black-footed ferrets born in captivity and then released into nature.

Back from the Brink of Extinction

Considered extinct until a small population was discovered in Wyoming in 1981 (only 18 individuals remained by 1985), the black-footed ferret is edging away from near extinction. Working closely with the U.S. Fish and Wildlife Service, the National Zoo and SCBI are helping save this endangered species and return it to the wild.

Reproduction to Reintroduction

The black-footed ferret is one of the most endangered animals in the world. Once inhabiting the grasslands of the western Great Plains, the black-footed ferret declined with the loss of the North American prairie ecosystem. Prairie dogs are the ferret’s primary prey, and only two percent of the original prairie dog habitat remains today.

The Black-Footed Ferret Recovery Plan, developed by the U.S. Fish and Wildlife Service, emphasizes natural breeding programs, developing assisted breeding, especially artificial insemination, and establishing multiple reintroduction sites.

The black-footed ferret breeding program depends on computerized matchmaking, ensuring that the most genetically appropriate individuals are mated together. This genetic management occurs through a Species Survival Plan, a group of zoos and conservation organizations working together to save the species. From those original 18 animals, approximately 250 ferrets reside in breeding facilities and about 800 animals are now in the wild.

JoGayle Howard places frozen semen into a liquid nitrogen tank.

Black-Footed Ferret Genome Resource Bank

SCBI-Front Royal maintains the Black-Footed Ferret Genome Resource Bank, a repository of frozen semen from the most valuable males. The bank is used for assisted breeding and serves as insurance against future catastrophes (for example, disease).

SCBI-Front Royal Breeding Program

The National Zoo’s Smithsonian Conservation Biology Institute in Front Royal (SCBI-Front Royal)has played an essential role in the recovery of the black-footed ferret. SCBI-Front Royal was the first institution outside of Wyoming invited to begin a breeding program. SCBI-Front Royal continues to make valuable contributions to the science of animal husbandry, reproduction, nutrition, veterinary medicine, pathology and reintroduction. Since 1988, SCBI-Front Royal has produced more than 130 black-footed ferret kits after natural matings.

Assisted Reproductive Technology

Many black-footed ferrets do not breed because of behavioral incompatibility or improper breeding positioning. For this reason, our scientists have developed artificial insemination. The Zoo's JoGayle Howard pioneered methods for depositing sperm directly into the uterus, resulting in the birth of more than 100 kits. Reproductive technologies also are used routinely for management including: checking male fertility before mating, overcoming infertility, and ensuring that every genetically valuable individual reproduces to maintain as much genetic diversity as possible. This, in turn, ensures that the population remains vigorous and reproductively sound long into the future.