Dynamics of green algae and its associated fauna in the Ria Formosa: is herbivory important?

The Ria Formosa is a system of salt marshes and tidal flats, separated from the Atlantic by a belt of sand dunes that extends for 55 Km along the southern coast of Portugal. A striking phenomenon, which has been registered every winter since 1988, is an intense bloom of green macroalgae, mainly Ulvales (Ulva spp. and Enteromorpha spp.) These blooms appear the first rain falls in autumn and disappear gradually during the following spring (Sprung, 1994). A distinct community of benthic fauna is associated with these green algae. The objective of this work was to study in the western part of Ria Formosa, if the Ulvales were controlled by herbivorous macroepifauna