Adara, a female dama gazelle, died Monday, Smithsonian’s National Zoo announced on Friday.
Adara, known as the “boss lady” of the zoo’s dama gazelle herd, was 14—six years older than the median life expectancy of her critically endangered species in human care. She had developed arthritis in her leg and was showing signs that were “consistent with an aggressive tumor” in a recent radiograph. Adara eventually refused to take pain medication and was found lame on Monday, leading to the decision by the zoo’s animal care staff to euthanize her.
Adara will be remembered for her habit of getting hay stuck on her horns, a condition the staff referred to as her “hay hats.” She was a mother of four and grandmother, and “seemed to enjoy sparring with calves,” a zoo release says. She arrived at the zoo in 2008 from Zoo Miami as part of the Association of Zoos and Aquariums’ Species Survival Plan.