The St. Louis Zoo hopes to release newly hatched Ozark hellbenders — the first ever bred in captivity — into Missouri rivers and replenish the endangered large salamander sometimes known as a 'snot otter."
The zoo has been working with the Missouri Department of Conservation for 10 years to try to breed the Ozark hellbender, one of two subspecies of the hellbender that is native to southern Missouri and northern Arkansas.
Success came on Nov. 15, and since then, 63 young hellbenders have hatched at the zoo. A clutch of an additional 120 eggs is expected to hatch in the next several days. The zoo plans to release the animals into Missouri rivers after the amphibians reach maturity, about three to eight years from now.
The breeding operation has been in the works for a decade — mostly in the "bio-secure" basement of the zoo's historic Herpetarium building. There, a floor beneath where children gawk at pythons and dart frogs, zookeepers have tried to coax captive hellbenders into reproduction. "You can't just breed these things in a standard aquarium, even a 100-gallon one," said Jeff Ettling, the zoo's curator of herpetology and aquatics. "You need space — a lot of space."
The zoo created a 32-foot simulated stream in the lab, complete with the rocks and other natural features of the Ozarks. Temperature, lighting and water conditions have to be just right for females to lay eggs and for males to fertilize them. The breeding area has its own air supply, and zookeepers who work with other amphibians and reptiles in the building don't work with the hellbenders for fear they might contaminate the breeding environment, Ettling said.
After several failed attempts, the zoo discovered the right combination of conditions this year to breed hellbenders, which can reach two feet in length. And that means when the adult hellbender population is counted, the zoo could become home to more than 450 of the endangered amphibian.
Only about 600 are believed to live in the waters of south-central Missouri and northern Arkansas, where as many as 8,000 once lived.
Ettling said the rapid decline is likely a combination of environmental change, a fungus that kills amphibians, and human poachers who capture hellbenders and sell them to collectors, often overseas. Now that the zoo has figured out how to breed Ozark hellbenders in captivity, the next step is fixing the conditions in the wild that have contributed to their decline. "We have a 15- to 20-year window to reverse this decline," Jeff Briggler, a herpetologist with the Missouri Department of Conservation, said in a prepared statement. "We don't want the animal disappearing on our watch."