SEA turtles help fertilise the dunes where they lay their eggs, says an ecologist from Florida, who believes their unhatched eggs make an important contribution to the health of the beach.

Coastal dunes are notoriously fragile, providing barely enough nutrients to support the animals and plants living on them. According to Sarah Bouchard of the University of Florida in Gainesville, California, the loggerhead turtles that lay their eggs in the dunes are lifesavers. They provide a net gain of nutrients to the ecosystem's total energy in two ways: they feed elsewhere, and ' any of their eggs that fail to hatch decompose and release substantial nutrients. Bouchard monitored 97 turtle nests on Melbourne beach in Florida containing a total of 10,608 eggs. Only 42 per cent of theses eggs hatched successfully. Of the rest, over half were eaten by predators, and the remainder decayed, fertilising the sand and soil.