Search

Dopamine is produced by Ulvaria obscura, a bloom-forming green alga that occurs from the mid intertidal to the shallow subtidal zones of North Pacific and North Atlantic shores. Its concentrations in the alga are approximately 0.5–1% of the alga's fresh mass. When experimentally desiccated and rehydrated at ecologically realistic densities, Ulvaria releases dopamine, resulting in seawater dopamine concentrations that can exceed 500 μM. Thus, dopamine could be responsible for previous reports of bioactivity by Ulvaria exudates. We tested this hypothesis by measuring the effects of dopamine in seawater on co-occurring macroalgae and crab larvae and juveniles. We ran assays that examined the effects of a range of dopamine concentrations on the growth of the green alga Ulva lactuca, on the germination of zygotes of the brown alga Fucus distichus, and on the survival, time to metamorphosis and time to first molt of crab (Metacarcinus magister and Cancer oregonensis) larvae and juveniles. Dopamine began to inhi...