Effect of microbial films on settlement of bryozoan larvae (Bugula simplex,B. stolonifera and B. turrita)

The influence of microbial films on larval settlement was studied for sympatric species of cellularioid cheilostome bryozoans (Bugula simplex, B. stolonifera, and B. turrita). Settlement experiments were conducted in the laboratory in 1981 with and without a choice of filmed or unfilmed substrates. When given a choice of substrates, the larvae of all three bryozoan species significantly preferred the filmed substrate. When not given a choice of substrates, both B. simplex and B. turrita larvae tended not to settle on the unfilmed substrate, while the filmed and unfilmed substrates were equally attractive to B. stolonifera. Microbial films enhanced the settlement of all three species.