A 37-year-old siamang gibbon at the San Diego Zoo recently gave birth to the zoo’s first siamang baby in 12 years despite being on birth control, the zoo announced Friday.
The siamang, named Eloise, gave birth in its exhibit on Nov. 12 while zoo volunteers and guests looked on. Eloise and a 35-year-old male siamang had conceived six baby gibbons in the past, but the newest one came as a surprise to zoo officials.
Given that their genes had clearly been passed on multiple times, the zoo had limited the two siamangs’ fertility with chemical birth control for an undisclosed number of years prior to the surprise birth.
“It was amazing to see Eloise give birth this week, because she showed no outward signs of being pregnant,” said Zoo Animal Care Manager Jill Andrews. “We’re not certain why birth control didn’t work in this case, but as with humans, it is not uncommon for contraceptive failure to happen from time to time. Still, we are overjoyed — because any birth of an endangered species is a reason to celebrate.”
Siamangs are an endangered species of gibbon found in parts of India, Indonesia and Bangladesh. According to the zoo, their endangered classification by the International Union for Conservation of Nature is due to habitat loss brought on by logging and agriculture as well as illegal pet trading.
Zoo guests can visit the three siamangs along the zoo’s Orangutan Trail.
The zoo’s animal care staff will determine the baby’s gender in the coming months when they have a chance to give it a full health examination.
— City News Service







