A wandering population of the hexactinellid sponge Pheronema carpenteri on the continental slope off Morocco, Northwest Africa
In: Marine Ecology (Berlin). Blackwell: Berlin. ISSN 0173-9565; e-ISSN 1439-0485, more | |
Authors | | Top | - Barthel, D.
- Tendal, O.S., more
- Thiel, H.
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Abstract | A photo transect along the continental slope off Morocco, Northwest Africa revealed an extensive population of the hexactinellid sponge Pheronema carpenteri (thomson, 1869). The population forms a distinct band parallel to the depth contours between 740 and 820 m. Because of the long persistence of dead hexactinellid skeletons, living and dead individuals of P. carpenteri were recorded, together with the spicular remains of disintegrated individuals. Furthermore, the presence of small individuals and that of other epifaunal elements were recorded. The peaks of abundance of dead and living sponges, respectively. are not at the same depth, the maximum abundance of living individuals being above that of the dead ones; small, i.e., probably young P. carpenteri individuals were observed only in the upper zone. This can be interpreted as a successional phenomenon, i.e., the population of P. carpenteri has apparently ‘moved’ slowly up the slope. The fauna associated with the P. carpenteri population along the Moroccan coast seems to be much poorer than that associated with another band-shaped population in the Porcupine Seabight investigated by Bett & Rice (1992). indicating that the presence of dense hexactinellid populations does not invariably lead to conspicuous benthic faunal enrichment. |
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