Abstract

During the period of 20 April to 17 May 1978 an investigation on Hawaiian Monk Seal mortality was conducted.

This report concerns the findings dealing with the parasites of this investigation.

Necropsy material was examined from sixteen animals. Two animals were necropsied during the island visit while the remainder (fourteen) were in the form of preserved material recovered previously by two National Marine Fisheries Service Observers (Brian and Patti Johnson).

A total of five species of helminths and one species of acarine were recovered. The helminths were represented by one acanthocephalan (Corynosoma rauschi), three Cestodes (Diphyllobothrium cameroni, D. elegans, D. hians) and one Nematode (Contracaecum turgium). The single species of acarine (under study for identity at present) was recovered from a single host infesting the nasal and throat area. Heavy infections of all helminths were found with C. turgium being the most prevalent (in fourteen of sixteen animals) followed by D. cameroni (nine), D. hians (eight), C. rauschi (seven) and D. elegans (three). In addition, thirty-nine stool samples were collected and examined from six of the islands. The ova found were representative of the adults identified with the exception of a capillarid nematode-type egg from Lisianskiis.

Notes

Emaciated Monk Seals were found lying parallel to the water rather than pulling themselves farther up on the beach. They feed on lobster and a small white eel which can contain a large dosage of sequitoxin (a lipotoxin which comes from a dinoflagellate).