Oklahoma City Zoo veterinary caretakers are working to solve a very curious case; Bridget, the Zoo’s 18-year-old African lioness, has suddenly sprouted a mini-mane.
In males, manes develop at about one-year-old and are a product of increased production of the hormone testosterone. The OKC Zoo’s male lion, Hubert, 6, has a robust, dark mane while Tia, Bridget’s 18-year-old sister, remains mane-less. Bridget’s mane growth occurred between March and November 2017.
While female lions growing manes is rare, it’s not unheard of. Association of Zoos and Aquariums (AZA) Species Survival Plan vet advisor Dr. Mike Briggs spotted a female lion in Africa with a mane similar in appearance to Bridget’s. In 2011, a 13-year-old lioness at the National Zoo in South Africa began developing a mane. An issue with her ovaries resulted in excess testosterone production and once that was resolved, the mane receded. A group of five lionesses in the wilderness of Botswana were observed with manes in 2014. Because these lions came from the same pride and developed the manes at a young age, researchers believe a genetic component in this population resulted in this characteristic.
Veterinary staff and caretakers developed behavioral training methods that would allow them to safely draw blood from Bridget's tail without the need for anesthesia. They successfully obtained a blood sample last week and are currently awaiting results. Aside from a natural genetic component, another potential condition causing the mane growth could be a benign tumor located on her adrenal or pituitary gland as these regulate hormones like testosterone.
Zoo veterinary staff will continue to monitor her closely, but this condition is not likely to affect Bridget’s quality of life. They report that, other than the extra hair, they see no change in her health status.
Bridget was born at the Oklahoma City Zoo's Lion Overlook in 1999 and produced a litter of cubs in 2007. The AZA reports the median life expectancy for lions is 16.9 years.
Photos: Amanda Sorenson, Animal Caretaker & Jennifer D'Agostino, DVM, Director of Veterinary Services