ABSTRACT
We have studied the in situ growth of adult Paracentrotus lividus, in a lagoon (e. g. Corsica, France). The food provided was the seagrass Cymodocea nodosa for the first enclosure, a vegetable-based artificial feed for the second and an animal-based artificial feed for the third. The growth rate of P. lividus, over a period of 20 months, was comparable to growth rate models established for open sea populations. The food provided had an effect on the growth rate, which was higher for sea urchins fed the animal-based artificial feed than for specimens fed Cymodocea nodosa, a preferred item in their natural diet. Variations in growth according to season were observed. These variations may be partly explained by strong temperature fluctuation recorded in the lagoon, associated with the physiological condition of the sea urchins (gonadal cycle).
