Randall E. Junge, MS, DVM, DACZM
Director of Animal Health, St. Louis Zoo, St. Louis, MO, USA
The hellbender (Cryptobranchus alleganiesis) is a large aquatic salamander native to the United States.6,10 Hellbenders in the wild are threatened by stream impoundment, channelization, agricultural runoff (chemical and siltation), disturbances caused by recreational use, and thermal changes.11 Batrachochytrium dendrobatidis (Bd) and ranavirus infection have been identified in wild populations2,3,13 but the significance is unknown. Several gastrointestinal parasites have also been detected, but none appear to be clinically significant.4,12 Leeches (Placobdella cryptobranchii) are often present8 and may be the vector of Trypanosoma cryptobranchi. Traumatic injuries to digits and appendages appear to be relatively common, and wild hellbenders are frequently found missing digits or limbs.5
In captivity, Bd may be significant in compromised hellbenders. Saprolegniasis is usually superficial and often associated with dermal lesions. Wounds may occur from intraspecific aggression, trauma, or exhibit materials. Persistent wounds may be a source of infection leading to sepsis. Hellbenders can be anesthetized with tricaine methanesulfonate (MS-222; 0.025%, or 250 mg/L). For surgical procedures, absorbable suture may dehisce; therefore, it is recommended to use nylon suture material in both internal and external layers. Radiography and ultrasonography are useful imaging modalities. Phlebotomy is performed from the caudal vein located along the ventral aspect of the tail. Injectable antibiotics are preferred to oral or topical (soaks) administration in hellbenders.7 Antifungal therapy may be necessary for management of Bd infections. Itraconazole soaks,9 hyperthermia,14 and topical chloramphenicol1 may be effective.
Thanks to St. Louis Zoo Herpetology Department (J. Ettling, M. Wanner, C. Schuette) and Missouri Department of Conservation (J. Briggler) for letting me be on the team.
1. Bishop, P.J., R. Speare, R. Poulter, M. Butler, B. Speare, A. Hyatt, V. Olson, and A. Haigh. 2009. Elimination of the amphibian chytrid fungus Batrachochytrium dendrobatidis by Archey’s frog Leiopelma archeyi. Dis. Aquat. Org. 84:9–15.
2. Briggler J.T., K.A. Larson, and K.J. Irwin. 2008. Presence of the amphibian chytrid fungus (Batrachochytrium dendrobatidis) on hellbenders (Cryptobranchus alleganiensis) in the Ozark Highlands. Herpet. Rev. 39:443–444.
3. Gray, M. 2010. University of Tennessee Center for Wildlife Health. Personal communication.
4. Hasegawa, H., and Y. Ikeda. 2003. Helminths from the hellbender, Cryptobranchus alleganiensis (Urodela: Cryptobranchidae), in Missouri, USA. Comp. Parasitol. 70:60–65.
5. Hiler, W.R., B.A. Wheeler, and S.E. Trauth. 2005. Abnormalities in the Ozark hellbender (Cryptobranchus alleganiensis bishopi) in Arkansas: a comparison between two rivers with a historical perspective. J. Ark. Acad. Sci. 59:88–94.
6. Johnson, T.R. 1992. The amphibians and reptiles of Missouri. Jefferson City, Missouri Department of Conservation.
7. Junge, R.E. In press. Hellbender medicine. In: Fowler, M.E., and Miller, R.E. (eds.). Zoo and Wild Animal Medicine. 7th ed. 2011 publication date.
8. Moser, W.E., D.J. Richardson, B.A. Wheeler, K.J. Irwin, B.A. Daniels, S.E. Trauth, and D.J. Klemm. 2008. Placobdella cryptobranchii (Rhynchobdellida: Glossiphoniidae) on Cryptobranchus alleganiensis bishopi (Ozark Hellbender) in Arkansas and Missouri. Comp. Parasitol. 75:98–101.
9. Nichols, D.K., and E.W. Lamirande. 2001. Successful treatment of chytridiomycosis. Newsletter, CO. Herpet. Soc. 28:1–2.
10. Nickerson, M.A, and C.E. Mays. 1972. The hellbenders: North American “giant salamanders”. Milwaukee, Milwaukee Public Museum.
11. Solis, M.E., C.C. Liu, P. Nam, D.K. Niyogi, J.M. Bandeff, and Y.W. Huang. 2007. Occurrence of organic chemicals in two rivers inhabited by Ozark hellbenders (Cryptobranchus alleganiensis bishopi). Arch. Environ. Contam. Toxicol. 53:426–434.
12. Walton, A.C. 1942. The parasites of the Cryptobranchoidea (Amphibia: Caudata). J. Parasitol. 28:29.
13. Weiss, R.B, T.M. Wolf, A.P. Pessier, J. Greathouse, and B.A. Wolfe. 2009. Health Assessment of Eastern hellbender (Cryptobranchus alleganiensis alleganiensis) populations in Ohio and West Virginia. In: Proceedings. Amer. Assoc. Zoo. Vet. Amer. Assoc. Wildl. Vet. Joint Conf.: 82.
14. Woodhams, D.C., R.A. Alford, and G. Marantelli. 2003. Emerging disease of amphibians cured by elevated body temperature. Dis. Aquat. Org. 55:65–67.