Cryptococcus in a Wild Loon (Gavia immer)


  • Mark A. Pokras, BS, DVM Wildlife Clinic, Tufts University Cummings School of Veterinary Medicine
  • Rose Miconi, BS Wildlife Clinic at Tufts University Cummings School of Veterinary Medicine
  • Steven Engler, BS, DVM, Dipl. AC VP Antech Diagnostics
  • Alison Hazel, BS, DVM Liverpool Animal Health Center
  • Romona Haebler, BS, PhD, Dipl. ACVP US Environmental Protection Agency



Loon, Gavia, Cryptococcus, avian, fungal infection


A debilitated adult male common loon (Gavia immer) was taken to a veterinary practice in Liverpool, NY where it later died. Subsequently it was sent to Tufts Wildlife Clinic as part of a regional mortality study. During the necropsy, pathology involving most organ systems was noted. Microbiologic and histopathologic examination revealed an overwhelming infection by the fungus Cryptococcus spp.


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Author Biographies

Mark A. Pokras, BS, DVM, Wildlife Clinic, Tufts University Cummings School of Veterinary Medicine

Mark Pokras is Director of the Wildlife Clinic at Tufts University. He is heavily involved in conservation medicine and continues to inspire veterinary students to follow their hearts and strive to better our world.

Rose Miconi, BS, Wildlife Clinic at Tufts University Cummings School of Veterinary Medicine

Rose Miconi has a BS in wildlife biology from the University of Rhode Island and for many years worked with Dr. Pokras on loon conservation issues.

Steven Engler, BS, DVM, Dipl. AC VP, Antech Diagnostics

Steven Engler is a veterinary pathologist who taught for many years at Tufts Cummings School of Veterinary Medicine. He currently provides diagnostic pathology services for Antech Diagnostics, Inc.

Alison Hazel, BS, DVM, Liverpool Animal Health Center

Alison Hazel worked in upstate New York practicing small animal medicine and providing local rehabilitators with veterinary services. In 1998 she was voted Wildlife Veterinarian of the Year for New York State.

Romona Haebler, BS, PhD, Dipl. ACVP, US Environmental Protection Agency

Romona Haebler is a veterinary pathologist at the US EPA’s Atlantic Ecology Division, in Rhode Island. Mona has many years of experience studying disease and toxicologic threats to marine mammals, birds, and reptiles.


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How to Cite

Pokras, M., Miconi, R., Engler, S., Hazel, A., & Haebler, R. (2009). Cryptococcus in a Wild Loon (Gavia immer). Wildlife Rehabilitation Bulletin, 27(1), 18–23.



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