ASHEBORO—For the second time in a week, the North Carolina Zoo has suffered the loss of an iconic animal and one of its most popular attractions. Aquila, a 21-year-old male polar bear, was found dead in his off-exhibit holding quarters when keepers arrived for work around 7 a.m. Tuesday.

According to General Curator Ken Reininger, Aquila had shown no previous signs of illness and appeared in good condition when keepers left Monday evening. His loss comes one week after the death of the zoo’s adult male gorilla, Nkosi, to a yet-to-be identified illness. The zoo is still awaiting laboratory test results to help determine the gorilla’s cause of death.

 A necropsy, or animal autopsy, conducted Tuesday afternoon on the polar bear by zoo veterinarians, revealed that the animal died from a ruptured stomach which emptied the stomach contents into the chest causing the lungs to collapse. According to Zoo Senior Veterinarian Dr. Ryan DeVoe, Aquila had suffered from a “diaphragmatic hernia.” Part of the stomach had become entrapped in the hernia, causing the stomach to rupture, DeVoe explained.

Aquila had returned to the N.C. Zoo in April of this year after a two-year stay at the Detroit Zoo. Aquila and the zoo’s other male polar bear, Wihelm, had both been sent to other zoos in summer 2011 as the zoo began an $8.5 million renovation and expansion of its polar bear exhibit. Aquila returned when renovations to the older part of the exhibit were completed. Construction on the expansion continues and is expected to be complete in fall 2014. Meanwhile, Wilhelm remains at the Milwaukee Zoo and no decision on the timing of his return has been made.

Aquila was one of a set of triplet polar bears—two males and a female-- born at the Louisville Zoo in November 1992. The three siblings became the first bears to be exhibited in the N.C. Zoo’s polar bear exhibit when it opened as part of the zoo’s new 200-acre North America exhibit region in August 1994. Over the ensuing years both of Aquila’s siblings passed away. Aquila also spent time back at the Louisville Zoo beginning in June 2002 and later at the Cleveland Zoo after the N.C. Zoo acquired two polar bears confiscated by the U.S. Fish and Wildlife Service from a circus in Puerto Rico. Wilhelm is one of those confiscated bears. The other, Masha, also passed away in 2009, prompting Aquila’s first return to Asheboro.