Corolla, N.C. — A group that monitors endangered species says that situation of the two wild horse herds on the Outer Banks is worsening.

The American Livestock Breed Conservancy, a Pittsboro-based nonprofit that promotes endangered livestock and poultry breeds, moved the Corolla and Shackleford herds from the threatened category into the critical category. The next category is extinction.

Approximately 110 horses roam the Shackleford Banks, and 89 horses inhabit the northern Outer Banks in Currituck County. Both herds are listed by the ALBC as Colonial Spanish Mustangs.

The federal Shackleford Act stipulates that herd should have a minimum of 100 horses to maintain genetic viability. The Currituck Wild Horse Management Plan calls for that herd to stay at a minimum of 60 horses.

Work by Dr. E. Gus Cothran, a leading equine geneticist and expert on feral horses, however, shows that the Currituck herd should also have at least 100 horses to maintain genetic diversity, the ALBC claims.

The Corolla Wild Horse Fund has gathered genetic samples from the horses for Cothran to determine the herd's baseline genetic health. North Carolina State University has agreed to draw up a concept paper to help the CWHF get funding for an ecological study of the land roamed by the horses.

The CWHF has also worked with the Horse of the Americas registry to breed Banker horses with other horses of the Colonial Spanish Mustang strain. The off-site breeding program's first foal will be born this spring at Mill Swamp Indian Horses in Smithfield, Va.

Successful off-site breeding would help the Banker strain survive a localized disaster, such disease, a natural disaster or genetic collapse, CWHF officials said.