Population Dynamics and Overgrowth of the Sea FanEunicella cavolini(Coelenterata: Octocorallia)

doi:10.1006/ecss.1996.0038

Estuarine, Coastal and Shelf Science

Volume 42, Issue 5, May 1996, Pages 583-595

https://doi.org/10.1006/ecss.1996.0038 Get rights and content

Abstract

The population dynamics ofEunicella cavoliniKoch was investigated from 1989–91 at three study sites in the Bay of Calvi (Corsica, France). Population density was highest in the channel (149–180 colonies m⁻²), intermediate at the wall (54–66 colonies m⁻²) and lowest at the boulders (15–19 colonies m⁻²). Mortality, expressed as percentage of colonies that died within 1 year of investigation, did not differ between the study sites and showed large variability (8·3–26·7%). Expressed as percentage of new colonies on total colony numbers, recruitment was highest in the channel (11·7–20·1%), intermediate at the wall (7·4–12·0%) and lowest at the boulders (0–8·3%). A growth formula forE. cavolinideveloped in an earlier study (Velimirov, 1975) was shown to be suitable for the investigated study sites. The estimated maximum age was 21 years. Age frequency distribution did not vary strongly between subsequent years during the 3-year investigation. However, the age structure differed strongly between study sites. Overgrowth of colonies was highest at the boulders, intermediate at the wall and lowest in the channel. Overgrowth increased with colony age until the age of 4 years. Mortality ofE. cavoliniis mainly due to detachment and overgrowth.

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^f1: Present address: National Research Center for Biotechnology, Division Microbiology, Mascheroder Weg 1, D-38124 Braunschweig, Germany.

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Regular ArticlePopulation Dynamics and Overgrowth of the Sea FanEunicella cavolini(Coelenterata: Octocorallia)

Abstract

Regular Article
Population Dynamics and Overgrowth of the Sea FanEunicella cavolini(Coelenterata: Octocorallia)