ENVIRONMENTAL-EFFECTS ON THE GROWTH-RATE OF INTERTIDAL INVERTEBRATES AND SOME IMPLICATIONS FOR FORAGING WADERS

The paper describes effects of intertidal height and sediment type on growth rate of the bivalves Cerastoderma edule, Macoma balthica, Mya a renaria, Mytilus edulis and Scrobicularia plana, and of the worms Aren icola marina, Nephtys hombergii and Nereis diversicolor in the eastern part of the Dutch Wadden Sea. In most species, exposure time was nega tively correlated with length growth, although interfering effects of sediment type could not be ruled out. When controlled for the effects of exposure time, clay content of the sediment appeared to affect the growth of all species, but in different ways. The variation was relate d to the foraging methods of the invertebrates. Foraging waders may us e the spatial variation in growth rate of the invertebrates to optimiz e the exploitation of individual cohorts.