To read more about our conservation efforts and the 2014 releases, read this story from the Toledo Zoo's newsletter (part 1, part 2) and watch the zoo's video below.
Status and Conservation of the Eastern Hellbender in OhioCurrently, we are working on increasing our capacity to rear hellbenders and expanding our egg collection efforts to capture as much of the remaining genetic diversity as possible. Just as important, we are working on identifying issues that are degrading stream habitats (especially siltation) and looking for ways to restore hellbender habitat.
The Eastern Hellbender (Cryptobranchus alleganiensis alleganiensis) is one of only two completely aquatic salamanders found in the state of Ohio. Within the state it has historically been found in nearly all of the major systems draining into the Ohio River.
Previous surveys conducted during the drought years of the mid-1980s and in 2000 resulted in the capture of 112 individuals from 15 waterways, more than 50% of the total number of documented hellbender occurrences in the state at the time. At the conclusion of these initial surveys, the species was listed as endangered by the Ohio Division of Wildlife.
The current survey began in 2006 and has included mark-recapture, examination of the prevalence of the amphibian chytrid fungus (Bd) on hellbenders and in hellbender habitat, and assessments of habitat quality.
A total of 1487 person-hours spent searching has resulted in 89 observations of 79 individual hellbenders in 11 Ohio waterways. The number of hellbenders captured per person-hour searching has declined by nearly 82% in the waterways where they were previously documented, with no hellbenders detected in seven of the 15 (47%) waterways.
Hellbenders were found in four waterways where they were not previously detected or where surveys were not previously performed. In seven of the 11 (64%) waterways, no individuals <45 cm were encountered, and together with the low relative abundance, these populations do not appear to be viable. The lack of successful recruitment of young into populations appears to be the mechanism of hellbender decline in both Ohio and elsewhere throughout the species' range.
Skin swabs of hellbenders and sympatric amphibians found “possible positives” for infection by Bd (amphibian chytrid fungus) on only three Common Mudpuppies (Necturus maculosus maculosus). All water tests for Bd were negative. Previous sampling by The Wilds detected Bd on one hellbender, and the pathogen seems to be widespread in many parts of the state.
Analysis of organic compounds in waterways with extant, declining, and presumed extirpated hellbender populations do not support the hypothesis of a novel pollutant causing declines, although amphibians often respond unpredictably to the interactions of multiple stressors. At most sites tested, one or two phthalate compounds were detected, raising concern about the potential endocrine disrupting properties of these chemicals.
In order to maintain viable populations of the hellbender in Ohio, four recommendations are made:
1) Support conservation efforts in areas where viable populations currently exist;
2) Increase the use of existing conservation programs to protect hellbender habitat;
3) Investigate the feasibility of a repatriation/augmentation program for hellbenders in Ohio; and,
4) Continue to conduct mark-recapture surveys to monitor populations, collect demographic and growth data, and provide on-the-ground outreach and early detection of potential threats.
From Surveys to Implementation
More is known about the status of hellbenders in Ohio than any other state, with the exception of Missouri. Due to the widespread decline of hellbenders in the state, action must be taken now to prevent their extirpation.
The Ohio Hellbender Partnership consists of representatives of the Ohio Division of Wildlife, the US Fish and Wildlife Service, several Ohio Zoos (Columbus Zoo, the Wilds, Toledo Zoo, Akron Zoo), the Ohio EPA, local soil and water conservation districts, and college/university researchers and students. We have been meeting regularly since the completion of statewide surveys to discuss strategies for reversing the decline of the hellbender in Ohio.
In conjunction with the Ohio Division of Wildlife and the Ohio Hellbender Partnership, I was the lead author on the Division's "Eastern Hellbender Ohio Conservation Plan." This plan outlines strategies and methods for the conservation and recovery of the Eastern Hellbender in Ohio from 2012-2017. Included in this document are summaries of the historic and current status of the species in the state, as well as recovery goals and objectives. From the plan:
"The goal of hellbender conservation activities in Ohio is to restore hellbender populations to a point where they are no longer in danger of becoming extirpated and can be removed from the list of state endangered species. This goal will be reached when multiple viable (self-sustaining) populations are established in at least six watersheds."
To reach this goal, the Ohio Hellbender Partnership has embarked on a captive head-starting and repatriation program to return hellbenders to areas where they have been extirpated. In September 2011, Eastern Hellbender eggs were collected from an Ohio stream and transported to the Columbus Zoo and Aquarium for captive-rearing and eventual release back into the wild. This was only the second time a hellbender nest had been found in the state.
In 2012 and 2013, 3- and 4-year old hellbenders collected as eggs from a nest in neighboring West Virginia and reared at the Columbus Zoo became the first hellbenders to be released as part of the head-staring program. The released individuals underwent exhaustive medical screenings to ensure the released animals would not transmit exotic pathogens into their new environment.
Each hellbender was also implanted with a radiotelemetry device so that their fate could be tracked until the following spring.
Egg collection in 2012-2014 resulted in nests being located in five Ohio watersheds. The young from these eggs are now being housed at the Toledo Zoo, Columbus Zoo, and Omaha's Henry Doorly Zoo for head-starting. Over 600 Ohio hellbenders are now being reared in captivity! In 2014, 189 head-started individuals were released, the first time Ohio-sourced hellbenders have been released back into Ohio streams.