Disease Incidence Associated with Stranded Sea Turtles Triaged at Taronga Wildlife Hospital: A Retrospective Study
Kimberly Vinette Herrin, MS, DVM; Larry Vogelnest, BVSc, MVS, MACVSc; Frances Hulst, BVSc, MVS; Robert Johnson, BVSc, MACVSc, CertZooMed, BA, CMAVA; Karrie Rose, DVM, DVSc
Retrospective analysis (1985–2010) was performed to assess the disease status and eventual fate of 189 sea turtles triaged at the Taronga Wildlife Hospital (TWH). Sea turtles admitted to the hospital represented four of 6 species found in Australian waters: green turtle (Chelonia mydas) n=131, hawksbill turtle (Eretmochelys imbricata) n=30, loggerhead turtle (Caretta caretta) n= 16 and flatback turtle (Natator depressus) n=12. Significant increases in sea turtle admissions have occurred since the mid-1980s, which averaged two cases per year without release success. Since the mid-1990s, four species have been represented, averaging 15 cases per year with a release success nearing 13%. Release success has continued to increase to an average of 26% through the 2000s. Major reasons for presentation include trauma 27% (including boat strike, fishing gear entanglement, power plant entrapment), infectious disease 16%, impaction 12% (including plastic/foreign bodies), parasitism 10% and emaciation 5%. It is important to note that an epizootic systemic coccidiosis (Caryospora cheloniae) event of adult green turtles in 2002 accounted for a majority of the parasitism cases.1 In addition to clinical pathology, radiographs are critical diagnostic tools for disease diagnosis and useful prognostic indicators for rehabilitation success, particularly in cases of trauma, fishing hook ingestion, and pneumonia. Most critically, all sub-adult turtles with evident obstipation on radiographs have not been successfully rehabilitated. A further component of this study is to also correlate clinical findings (clinical pathology, radiographic changes) with necropsy findings in animals that died or were euthanatized.
Thank you to the Taronga Wildlife Hospital nursing staff for their ongoing care of stranded sea turtles and to Kaye Humphreys for her extensive contribution through laboratory diagnostics. Also, thank you to past veterinary interns Pru Harvey, Monica Bando and Kate Leach for their initial help in the data analysis.
1. Rose, K., Humphreys, K. Hearing R., Giles G., Bancroft C., Howarth K. An epizootic of systemic coccidiosis (Caryospora cheloniae) in green turtles (Chelonian mydas) along coastal NSW—a marine indicator of drought. Proceedings Wildlife Disease Association Conference, Saskatoon, Canada, 14 August 2003.