Bridget, an 18-year-old lioness at the Oklahoma City Zoo, has left veterinarians most curious about the mane she grew from March to November last year. Male lions develop their manes at about 1 year of age as a result of increased testosterone production. While female lions growing manes is rare, it’s not unheard of, according to zoo officials. Mike Briggs, DVM, Association of Zoos and Aquariums (AZA) Species Survival Plan veterinary advisor, 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 drew blood from Bridget’s tail and are currently awaiting results. A potential condition causing the mane growth could be a benign tumor located on her adrenal or pituitary gland, according to the zoo. Zoo veterinary staff said they will continue to monitor Bridget closely, but this condition is not likely to affect her quality of life. Zoo officials said that, other than the extra hair, they see no change in her health status. Tia, Bridget’s 18-year-old sister at the zoo, has not experienced any mane growth. Bridget was born at the Oklahoma City Zoo’s Lion Overlook in 1999 and produced a litter of cubs in 2007. The median life expectancy for lions is 16.9 years, according to the AZA.
