Ecology and host relationships of the whale-louse Isocyamus delphini (Amphipoda: Cyamidae) parasitizing long-finned pilot whales ( Globicephala melas) off the Faroe Islands (Northeast Atlantic)

• Published in: Canadian Journal of Zoology
• Main Authors: Balbuena, J. A., Raga, J. A.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Canadian Science Publishing 1991
• Subjects: Faroe Islands; Northeast Atlantic
• Online Access: http://dx.doi.org/10.1139/z91-021; http://www.nrcresearchpress.com/doi/pdf/10.1139/z91-021

In cooperation with an international research program concerning the biology of the long-finned pilot whale (Globicephala melas) in the Northeast Atlantic, 152 pilot whales taken in the Faroese drive fishery were examined for ectoparasites. The whale-louse Isocyamus delphini was detected on 45(29.61%) of the whales. Four whale groups were established, according to sex and sexual status: immature or pubertal males, mature males, immature females, and mature females. Whale-lice showed over-dispersed distributions on these four whale groups. Prevalence, abundance, and spatial distribution of I. delphini on sexually mature males were significantly different from those on the other whale classes. Heavy infections were only observed on mature males. Behavioral differences between males and females and between adults and juveniles could account for these results. The genital slit was by far the site most preferred by I. delphini. This location seems to be one of the few that offers appropriate shelter for this cyamid.