Publication

2005-08

English

http://archimer.ifremer.fr/doc/2005/publication-602.pdf (0.32 Mo)

Cambridge University Press 2005

Bayed Abdellatif¹, Quiniou Francoise², Benrha Ali³, Guillou Monique⁴

1 : Inst Sci, Rabat 10106, Morocco.
2 : IFREMER, Dept Biogeochim & Ecotoxicol, Ctr Brest, F-29280 Plouzane, France.
3 : Inst Natl Rech Halieut, Lab Ecotoxicol, Casablanca, Morocco.
4 : UBO, Inst Univ Europeen Mer, CNRS, UMR 6539,LEMAR, F-29280 Plouzane, France.

Journal of the Marine Biological Association of the United Kingdom (0025-3154) (Cambridge University Press), 2005-08 , Vol. 85 , N. 4 , P. 999-1007

11

Biology, Ecology

Moroccan Atlantic, Growth, Population, Juvenile, Reproduction

The condition of three intertidal Paracentrotus lividus populations, which inhabit an area between Rabat and Casablanca (Morocco) known by its high wave energy and its substantial anthropogenic disturbances were described. The growth rate of the juvenile sea urchins in this intertidal zone was low compared with more sheltered populations. A sharp increase in the gonad index was observed between January and March at the beginning of a period of algal production, and was concomitant with increases in seawater temperature and food consumption rate. This gonad index increase was followed by a single spawning period occurring between March and June, probably triggered by the phytoplankton bloom induced by upwelling conditions. Larval development in all three populations was severely inhibited and could be explained, in part, by high and generalized Cu contamination throughout the region. Specific contamination of particular populations by Pb or Hg was attributed to local industries and the incomplete dispersion of pollutants in spite of the high hydrodynamics along the Moroccan Atlantic coast. One of the three populations studied showed strong indications of abnormal development; the degradation of its condition appeared to be due to the presence of a wadi (temporary river) which can seasonally reduce the salinity, directly affecting the sea urchin physiology and indirectly enhancing the metal toxicity.