Ecology of helminth parasitism in Puffinus gravis (Procellariiformes) on the breeding grounds at Gough Island

• Published in: Canadian Journal of Zoology
• Main Authors: Hoberg, Eric P., Ryan, Peter G.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Canadian Science Publishing 1989
• Subjects: Animal Science and Zoology; Ecology, Evolution, Behavior and Systematics; Austral; Gough; South Atlantic Ocean
• Online Access: http://dx.doi.org/10.1139/z89-030; http://www.nrcresearchpress.com/doi/pdf/10.1139/z89-030

Great shearwaters, Puffinus gravis, on the breeding grounds at Gough Island in the central South Atlantic were hosts for seven species of gastrointestinal helminths (range, two to five species per host; abundance = 114–4016 parasites per host). Cestodes, including Tetrabothrius laccocephalus, Tetrabothrius diomedea, Tetrabothrius filiformis, and metacestodes of Tetrabothrius sp., a strigeid trematode, Cardiocephaloides physalis, and an acanthocephalan, Corynosoma australe, occurred in the small intestine. Nematodes, Seuratia shipleyi and larvae of Contracaecum sp., were found in the proventriculus. Great shearwaters had not previously been recognized as hosts for T. filiformis, T. diomedea, and Cardiocephaloides, while C. australe is reported for the first time in an avian host. Populations of the five most abundant and prevalent helminths (Tetrabothrius spp. and Cardiocephaloides) were overdispersed. The patterns of diversity (measured by Brillouin's index), species richness, and abundance in the intestinal helminth community from P. gravis were at the lower end of a continuum for equivalent communities in avian hosts from terrestrial and aquatic habitats. The predictable breeding phenology of P. gravis at Gough Island and the distribution of immature or recently acquired helminths indicated that the major component of the parasite fauna was derived in the South Atlantic Ocean adjacent to the breeding grounds during the austral spring. The distribution of helminth parasites of great shearwaters is discussed with reference to food habits and long-range migration of the hosts.