Trophic cues as possible triggers of mussel larval settlement in southeastern Brazil

Abstract

Oligotrophic conditions may impose a nutritional challenge for the larval and early post-larval development of bivalves during the search for a suitable benthic habitat. Here we investigated what settlement cues might be important for mytilid populations in southeastern Brazil. Our results point to a trophic trigger mediating larval settlement that may include an effect of saturated fatty acids, probably linked to organic detritus and bacterial production deriving from terrestrial inputs. The prevalence of drifting in this population suggests it may be a strategy for individuals to delay final settlement until encountering favorable trophic environmental conditions.

Keywords

• brachidontes solisianus
• shell morphometry
• prodissoconch ii
• dissoconch
• juvenile drifting