Hellbender

Hellbender Salamander Hatches at Nashville Zoo

Hellbender young - January 2016

On October 11, 2015, the Nashville Zoo was successful in hatching an Eastern Hellbender that was the result of an egg being artificially fertilized with cryopreserved sperm; an achievement that had only been successful once before in an internal fertilizing Tiger Salamander in 2014. Moreover, this Hellbender is the first externally fertilizing salamander to be produced utilizing cryopreserved sperm.

“It’s a pretty big deal for the conservation of this species and all amphibians,” said Dale McGinnity, Ectotherm Curator. “This accomplishment means we can collect and preserve milt (seminal fluid containing sperm) from wild populations without removing Hellbenders from their environment. Cryopreserved sperm may remain viable for hundreds to thousands of years when kept at ultra-low temperatures with liquid nitrogen. ”

Many of the world’s amphibian species are disappearing from the planet due to pollution, habitat loss, and emerging diseases. Hellbenders, along with their close cousins the Japanese and Chinese Giant Salamanders, are the largest amphibians in the world; they are evolutionarily distinct and have remained relatively unchanged since the age of the dinosaurs. All three species are now in decline and may be threatened with extinction unless conservation programs are developed.

Hellbender tadpole 2015 - Sherri ReinschPhoto Credits: Nashville Zoo and Sherri Reinsch

The St. Louis Zoo reproduced Ozark Hellbenders naturally in an artificial stream system for the first time in 2011. The following year, Nashville Zoo successfully hatched two Hellbenders using artificial fertilization. The latest accomplishment is one more step in developing assisted reproductive technology (ART) for captive Hellbenders.

Once ART is fully developed, milt collected and cryopreserved from specimens may be used to fertilize eggs to create a genetically diverse group to boost isolated wild populations. In the future, cryopreserved sperm may be utilized to fertilize eggs to repopulate extinct populations. Nashville Zoo staff has already cryopreserved milt from 4 watersheds, which is believed to be the first gene bank developed for any salamander species.

“We really could not have done this alone,” said McGinnity. “Our Zoo’s Amphibian Specialist, Sherri Reinsch, and our Veterinary staff made the project possible. This success would not have been possible without the collaboration other researchers including Dr. Robert Browne, an Australian cryobiologist; Dr. Vance Trudeau, a Canadian endocrinologist; Dr. Joe Greathouse; Dr. Michael Freake; Dr. Brian Miller; Dr. Dalen Agnew; Dr. Carla Carleton; and Dr. Sally Nofs. A special thanks goes to Bill Reeves, the Chief of Biodiversity for the Tennessee Wildlife Resources Agency for the State Wildlife Grant that helped to fund this work which also included statewide surveys, gene banking, disease testing, and genetic work for hellbenders in Tennessee.”

Continue reading "Hellbender Salamander Hatches at Nashville Zoo" »


Nashville Zoo Makes History with First Captive Breeding of Eastern Hellbenders!

Hellbender-young-w-ruler---Amiee-Stubbs

Nashville Zoo is pleased to announce the captive breeding of Eastern Hellbenders for the first time as well as the first controlled breeding of any Hellbenders using biotechnology. The two Hellbenders were successfully hatched from eggs produced and artificially fertilized from the Zoo’s long-term captive animals.

“The successful hatching of the two Hellbenders is a result of a long-term collaborative project with a group of international researchers dedicated to saving this species,” said Dale McGinnity, ectotherm curator at Nashville Zoo. “This is an important first step and is in line with the Zoo’s commitment to the conservation and propagation of rare species.”

 An adult Ozark Hellbender, one of the world's largest Salamanders...

Hellbender-US-FISH-and-Wildlife

One of Nashville Zoo's adult Hellbenders...

Hellbender-adult-w-ruler---Amiee-Stubbs

Learn more about Nashville Zoo's Hellbender breeding efforts in the video below.

The two offspring were produced from a group of four Hellbenders living in an off-exhibit facility at the Zoo. 

“It has taken five years to develop assisted reproductive technologies for captive hellbenders,” said McGinnity. “We hope that with further refinement over the next few years, this species can be reliably reproduced using these techniques. This technology may then be used with a gene bank of cryopreserved sperm for Eastern hellbenders housed at the Nashville Zoo, to produce genetically diverse and fit offspring to suit various conservation needs.”

Hellbender-young---Amiee-StubbsSo small... for now... Photo credit: 1 & 4; Aimee Stubbs / Nashville Zoo, 2; U.S. Fish & Wildlife, 3; Christian Sperka / Nashville Zoo.

Continue reading "Nashville Zoo Makes History with First Captive Breeding of Eastern Hellbenders!" »