Faunistic control of Enteromorpha blooms: A field experiment

Gobies, Pomatoschistus microps (Krøeyer), were introduced to a series of cages on an estuarine mud-flat during the period in which the cover of Enteromorpha sp. was declining. They fed selectively on the grazers which either ingested Enteromorpha directly or browsed on micro-organisms attached to it and, therefore, significantly affected the breakdown rate of the alga. It is suggested that the balance between grazers and their predators may be at least partially responsible for the irregular development of Enteromorpha on estuarine mud-flats from year to year.