Prevalence of the commensal barnacle Xenobalanus globicipitis on cetacean species in the eastern tropical Pacific Ocean, and a review of global occurrence

Distribution and prevalence of the phoretic barnacle Xenobalanus on cetacean species are reported for 22 cetaceans in the eastern tropical Pacific Ocean (21 million km2). Four cetacean species are newly reported hosts for Xenobalanus: Bryde’s whale (Balaenoptera edeni), long-beaked common dolphin (Delphinus capensis), humpback whale (Megaptera novaeangliae), and spinner dolphin (Stenella longirostris). Sightings of Xenobalanus in pelagic waters are reported for the first time, and concentrations were located within three productive zones: near the Baja California peninsula, the Costa Rica Dome and waters extending west along the 10°N Thermocline Ridge, and near Peru and the Galapagos Archipelago. Greatest prevalence was observed on blue whales (Balaenoptera musculus) indicating that slow swim speeds are not necessary for effective barnacle settlement. Overall, prevalence and prevalence per sighting were generally lower than previously reported. The number of barnacles present on an individual whale was greatest for killer whales, indicating that Xenobalanus larvae may be patchily distributed. The broad geographic distribution and large number of cetacean hosts, indicate an extremely cosmopolitan distribution. A better understanding of the biology of Xenobalanus is needed before this species can be used as a biological tag.

Front pages with contents of No. 63, 2005

Cover. Contents.

News from Academy Bay

CDRS Research Highlights, 2004. Plants. Social Sciences. Vertebrates. Invasive Species Total Control Plan. Terrestrial Invertebrates. Project Isabela. Marine Sciences.

Back page of No. 63, 2005

Instructions for Authors. Back cover with map.

Front pages with contents of No. 38, 1983

Contents.

News from Academy Bay

Presidential visit. The extraordinary El nino year. The last of the Norwegians. Visits and events at the Darwin Research Station.

Front pages with contents of No. 37, 1983

Contents.

News from Academy Bay

Planning. A Galapagos marine park. The feral animals on Santiago Island. Can the Hawaiian Petrel be saved? Education and training programmes. Visitors and events at the Charles Darwin Station (May - October 1982).