Second-Generation Captive Hellbenders Hatch At Saint Louis Zoo

ST. LOUIS, MO — The Saint Louis Zoo, the Missouri Department of Conservation and U.S. Fish & Wildlife Service have announced the hatching of second-generation zoo-bred Ozark hellbenders at the Saint Louis Zoo, calling it "historic." Since October 6, 39 of the endangered salamanders have hatched at the zoo’s Charles H. Hoessle Herpetarium, according to a news release.

The zoo said the 7-year-old, first-time father is somewhat of a celebrity salamander. He and his clutchmates were the result of the zoo's (and the world’s) first successful captive breeding of Ozark hellbenders in November 2011. This is the first time any of the Saint Louis Zoo-bred, first-generation animals have successfully bred, officials said.

“This is truly a milestone and a credit to the expertise of our dedicated and caring Herpetarium team,” said Lauren Augustine, the zoo's curator of herpetology and director of the Saint Louis Zoo WildCare Institute Ron Goellner Center for Hellbender Conservation. “To know that the animals, which were bred, hatched and raised in our care, are now able to successfully reproduce is amazing. It means that we’re on the right track and that there’s hope for this species as a whole.”

(Subscribe to Patch for daily newsletters and the chance to win $100.)

“The Saint Louis Zoo has been a great partner in amphibian conservation for over 40 years,” said Jeff Briggler, a state herpetologist with the Missouri Department of Conservation. “We are hopeful that the first generation of Saint Louis Zoo-bred hellbenders now living in Missouri rivers are equally as successful in reproducing.”

In the wild, male hellbenders set up nest sites in the fall under large stones and wait for females to enter and deposit eggs to be fertilized, experts said. Males then defend the nests until the eggs hatch into larvae.

In mid-September, zoo staff watched the same thing play out in the zoo's outdoor simulated streams. Two female hellbenders that came to the zoo in 2011 as newly hatched larvae from a Department of Conservation hatchery laid 301 eggs in a nest that was guarded by a male who had been bred and hatched at the zoo. Forty-three of those eggs were fertile and were moved to climate- and water quality-controlled environments behind the scenes where they are being cared for by staff.

Between 2011 and 2016, officials said, the zoo has produced 5,183 successful hatchlings.

According to the Saint Louis Zoo, hellbenders are the largest aquatic salamanders in North America. And Missouri is the only state that has both subspecies — the Ozark hellbender and the eastern hellbender. Both are listed as state endangered in Missouri, and the Ozark hellbender also is federally endangered by the U.S. Fish and Wildlife Service.

"Rivers in south-central Missouri and adjacent Arkansas were estimated to once support over 27,000 Ozark hellbenders," Briggler said.

Due to drastic declines of wild populations, captive propagation became a priority in the long-term recovery of the species, officials said. Once the captive-bred larvae are 3 to 8 years old, they can then be released back into their natural habitat — the Ozark aquatic ecosystem.

In addition to the captive breeding efforts, officials said the zoo has also has been head-starting juvenile Ozark and eastern hellbenders, hatched from eggs collected in the wild, for future release. The success of a test release in 2008 suggested that captive-raised hellbenders can survive in the wild. Since 2008, a total of 5,792 juvenile Ozark hellbenders and 319 eastern hellbenders reared at the Zoo have been released into the wild to augment remaining populations in six different rivers. Missouri Department of Conservation staff are monitoring the success of these release animals in the wild.

Currently, the Saint Louis Zoo is head-starting over 2,112 juvenile hellbenders for future release.

The Saint Louis Zoo contributed to this report.

Photo and video courtesy of The Saint Louis Zoo