DAO 57:59-66 (2003)  -  doi:10.3354/dao057059

Protozoal and epitheliocystis-like infections in the introduced bluestripe snapper Lutjanus kasmira in Hawaii

Thierry M. Work1,*, Robert A. Rameyer1, Geraldine Takata2, Michael L. Kent3

1US Geological Survey, National Wildlife Health Center, Hawaii Field Station, 300 Ala Moana Blvd., Room 5-231, Honolulu, Hawaii 96850, USA
2Tripler Army Medical Center, Department of Pathology, 1 Jarrett White Road Honolulu, Hawaii 96859-5000, USA
3Center for Fish Disease Research, Oregon State University, Department of Microbiology, 220 Nash, Corvallis, Oregon 97331-3804, USA

ABSTRACT: The bluestripe snapper, or taape, was introduced into Hawaii in the 1950s and has since become very abundant throughout the archipelago. As part of a health survey of reef fish in Hawaii, we necropsied 120 taape collected from various coastal areas south of Oahu and examined fish histology for extraintestinal organisms. Forty-seven percent of taape were infected with an apicomplexan protozoan compatible with a coccidian. Infection was evident mainly in the spleen and, less commonly, the kidney. Prevalence of this coccidian increased with size of fish, and we saw no significant pathology associated with the organism. Twenty-six percent of taape were also infected with an epitheliocystis-like organism that occurred mainly in the kidney and, less commonly, the spleen. In contrast to the coccidian, fish mounted a notable inflammatory response to the epitheliocystis-like organism, and this inflammation appeared to increase in severity with age. Prevalence of the epitheliocystis-like organism infection increased with age, but infection was not seen in fish greater than 26.5 cm fork length. The high prevalence of coccidial infection in introduced taape prompts the concern that these organisms, along with the epitheliocystis-like organism, have the potential to be transmitted to native reef fish. Given the impact of other introduced microbial organisms on native Hawaiian fauna, there is a clear need to assess whether protozoa and bacteria are endemic to Hawaii, and whether they negatively impact native reef fish that closely associate with taape.

KEY WORDS: Bluestripe snapper · Lutjanus kasmira · Apicomplexa · Protozoa · Epitheliocystis-like organism · Pathology · Epizootiology

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