The Association of Zoos and Aquariums (AZA) announced that the Saint Louis Zoo received Significant Achievement in AZA’s 2016 North American Conservation Award for its Ozark Hellbender Augmentation Program. This annual award recognizes exceptional efforts toward regional habitat preservation, species restoration and support of biodiversity in the wild.
Ozark hellbenders were historically abundant in the spring-fed rivers of southern Missouri. Surveys in the early 1990s indicated that populations had declined by 70 percent over the past 40 years and that less than 600 individuals remained.
In 2002, as a result of this alarming decline, the Saint Louis Zoo’s WildCare Institute Ron Goellner Center for Hellbender Conservation began a collaborative propagation and head-start program for the Ozark hellbender in collaboration with the Missouri Department of Conservation and United States Fish and Wildlife Service.
Over the past 12 years, the Saint Louis Zoo has constructed three off-exhibit environmentally controlled rooms, two 40-foot outdoor streams and has dedicated three full-time keepers, one part-time keeper and one seasonal keeper staff to this conservation program. Saint Louis Zoo keeper staff has been simulating the seasonal changes in photoperiod and water temperature in an attempt to get the Ozark hellbenders to breed.
While eggs have been laid every year since 2007, it wasn’t until 2011 that the first fertile egg clutches were discovered. This breeding represented the first captive reproduction of either subspecies of hellbender. Successful captive breeding has since occurred annually (2012-’15), resulting in 4,890 larval hellbenders.
In addition to the captive propagation efforts the Saint Louis Zoo has also been head-starting juveniles 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 3,178 juvenile Ozark hellbenders reared at the Saint Louis Zoo have been released into the wild to augment remaining populations in four different streams (Bryant Creek, North Fork of the White River, Current River and Eleven Point River).
Based on the success of the captive propagation program, post-release survival of animals and dedicated individuals of various organizations, the future of the Ozark hellbender is looking optimistic. A successful captive propagation and head-start program may be the “safety net” needed to prevent this salamander, which is endemic to the Ozarks, from going extinct.
The Saint Louis Zoo is currently head-starting over 3,334 juvenile hellbenders for future release.
The Ozark hellbender (Cryptobranchus alleganiensis bishopi) is a large aquatic salamander that can reach lengths up to 20 inches. It has a restricted range and is only found in the cold-water rivers of south-central Missouri and adjacent north-central Arkansas.
Hellbenders have broad, flat heads, small lidless eyes and pronounced skin folds on the sides of their body. They can live 25-plus years, and their diet includes crayfish, fish, worms and snails. Large rocks on the river bottom provide refuge and nesting sites.