Fate of reef fish larvae trough ontogeny: advection or true mortality?

No abstracts are to be cited without prior reference to the author.

A three-dimensional structure of the in situ flow in the coastal region of Barbados served to model larval transport, using a turbulent scheme to predict diffusion, and the observed ontogenetic vertical migration behavior of larval cohorts of the bicolor damselfish (Stegastes partitus). Larval fluxes and observed declines in cohort densities were used to calculate age-specific instantaneous mortality rates throughout the entire pelagic duration. By tracking a total of 17 cohorts over station separation of 1 x 2 km, we were able to separate advective losses from natural mortality, which mean rates were estimated 0.38 d-1 and 0.20 d-1 , respectively. Both natural mortality rates and advective losses decreased with cohort age, the latter as a result of ontogenetic vertical migration. Differential retention rates in the near field during the pelagic phase caused variations in age-specific survival rates of local settlers.