REPRODUCTIVE STRATEGIES OF EPIALGAL BRYOZOANS

Bryozoans are common encrusting organisms in many shallow-water marine environments. Although reproducing sexually, their success as space o ccupiers resides largely in their capacity for colonial growth by zooi dal budding (regarded by some as a form of asexual reproduction). This paper examines the reproductive strategies of several bryozoan specie s commonly associated with the fronds of coastal macroalgae. These ran ge from ephemeral species that grow rapidly, reproduce and die (Electr a pilosa, Celleporella hyalina, Membranipora membranacea) to more or l ess annual species with well-developed reproductive and growth cycles (Flustrellidra hispida, Alcyonidium spp.). Whilst many of these bryozo ans brood relatively few short-lived lecithotrophic larvae, others pro duce large numbers of longer-lived planktotrophic larvae. The seasonal and daily patterns of larval release are described for selected speci es. Resource allocation to sexual and colonial functions is considered in the context of environment-genotype interactions. Reproductive str ategy is especially important in determining dispersal and colonising ability, and these in turn are major determinants of ecological patter n in epialgal bryozoan communities.