Giannini, F; Gili, J-M; Santangelo, G

Relationships between the spatial distribution of red coral Corallium rubrum and coexisting suspension feeders at Medas Islands Marine Protected Area (Spain)

2003

Italian Journal of Zoology

70

3

233-239

This paper addresses the spatial distribution of rocky bottom suspension feeders co-occurring in the same Mediterranean sciaphilic species assemblage, at Medas Islands Marine Protected Area (NE Spain), in which the octocoral Corallium rubrum is the most conspicuous component (in terms of cover area). One hundred and eighty photographic samples from 10 stations were examined. A significant negative association was found between the percent cover of C. rubrum and of the scleractinian cup coral Leptopsammia pruvoti. Nearest-Neighbour Distance (NND) analysis revealed a significant segregation between C. rubrum, L. pruvoti and Cystodites dellechiajei. This means that each species tends to have conspecifics as neighbours more frequently than other species. In only one station did red coral, once heavily harvested, exhibit low densities and no segregation. The asymmetric distribution of the NNDs between L. pruvoti and C. rubrum indicates that the patches of the former species are more homogeneously monospecific than that of the latter: in some cases L. pruvoti tends to wedge within crowded C. rubrum patches, but not vice versa. NNDs between red coral and L. pruvoti and between L. pruvoti conspecifics were greater than all the others. The intraspecific NNDs of C. rubrum decreases significantly with its increasing percent cover while L. pruvoti does not reduce inter-individual NNDs also if its percent cover increases. Overall, these findings indicate the tendency of L. pruvoti and C. rubrum to segregate one from the other at small distances, and suggest that the spacing of L. pruvoti could be determined by the aggressive behaviour of this scleractinian.

Coral/Nature conservation/Filter feeders/Marine parks/Aggressive behaviour/Patchiness/Interspecific relationships

10.1080/11250000309356523

ASFA Abstract