Let’s face it, in the on-going battle between wild nature and climate change, the world’s amphibians have been on the front lines; as a taxa, more species of amphibian have gone extinct or become critically threatened or endangered than almost any other animal group.
Many species of amphibian — which include frogs and salamanders — are adapted to unique ecological niches which, as they are degraded or destroyed, can no longer provide the crucial life support necessary for sustained survival.
Good News for a Giant Salamander
But there is occasionally good news for amphibians; case in point: the Ozark Hellbender, a large, endangered salamander found only in a few Missouri and Arkansas counties, has been successfully bred in captivity for the first time, thanks to a special collaboration between Ron Goellner of the the St. Louis Zoo and the Missouri Department of Conservation.
The announcement of 63 hatched, hellbender eggs and thriving larvae came on Nov. 30 last week, with the first of the hatchlings making its appearance on Nov. 15. Up to 120 more eggs may be hatched in the coming week. The baby hellbenders will retain their yolk sacs (see photo) for the next 45 to 60 days. Eventually, they will develop legs and lose their external gills by 18 months or more. Both parents were bred in the wild, with the male being a longer term zoo resident and the female arriving just this past September.
Ozark hellbenders (also known colloquially as “snot otters”) are the largest species of salamander in North America, and are related to the giant salamanders of China and Japan. Once they attain sexual maturity between 5 and 8 years, the amphibian can reach 2 feet long.
The salamanders can be returned to the wild any time between 3 and 8 years of age.
The Hellbender as ‘Baromenter’ Species
At one time, up to 8000 hellbenders (of which there are two subspecies) made their home in the cold, river bottoms of south-central Missouri and adjacent Arkansas. Today, only an estimated 600 exist in the entire world. Due to these small numbers, the amphibian was placed the Federal Endangered Species List, this past October.
And due to their adaptation to cool and clean river waters, hellbenders are also an indicator — a ‘barometer’ — of the health of the overall ecosystem (such is the case for most amphibians, which tend to succumb first to ecosystem changes, as with many of the world’s frogs over the past 20 years).
Saint Louis Zoo curator of herpetology and aquatics, Jeff Ettling, explains:
“Capillaries near the surface of the hellbender’s skin absorb oxygen directly from the water – as well as hormones, heavy metals and pesticides. If there is something in the water that is causing the hellbender population to decline, it can also be affecting the citizens who call the area home.”
Herpetologists at the Missouri Dept. of Conservation have gauged a 15 – 20 year window of opportunity to reverse the decline and save the species from extinction. The department cites a variety of causes for the amphibians’ decline: habitat loss due to stream siltation, pollution, disease (an all to common cause believed to be exacerbated in many cases by climate change) and, surprisingly, the illegal capture and foreign sales of hellbender pets.
Watch the St. Louis Zoo ‘b-roll’ (no audio) video of the first successful hellbender breeding project (article continues below):
How is the conservation effort being conducted?
Following several conservation project initiatives in 2001, a partnership between the state, the United States Fish & Wildlife Services and the Zoo was formed in 2004 to finance the building of state-of-the-art facilities including climate-controlled streams to breed the hellbender.
According to the St. Luis Zoo website,
“The hellbender propagation facilities include two outdoor streams that are 40 feet long and six feet deep. The area is landscaped with natural gravel, large rocks for hiding and artificial nest boxes, where the fertilized eggs were discovered. A nearby building houses state-of-the-art life support equipment used to filter the water and maintain the streams at the proper temperature.”
Additionally, the zoo’s herpetarium contains two climate-controlled rooms which recreate the hellbenders’ habitat and allow for monitoring and modification of environmental variables such as temperature, sunlight, and precipitation. The largest of the two rooms contains a simulated, native stream and houses a breeding group of adult hellbenders that were originally from the North Fork of the White River in Missouri. Off-spring from this group will eventually be released back into the wild.
To learn more, visit the The Ron Goellner Center for Hellbender Conservation
Photos: St Louis Zoo, Mark Wanner