Temporal fluctuations in a species southern range: mechanisms and implications for estimating edge location

David J Booth (1)

1    Fish Ecology Lab, University of Technology Sydney, PO Box 123 Broadway 2007 AUSTRALIA  David.Booth@uts.edu.au

A  key metric for climate-­‐change effects on species is the change in position of poleward range edge. However,  for marine species, with dispersive  larvae, this is problematic. Here, I present temporal patterns (interannual, seasonal) in recruitment of tropical reef fish species into  SE  Australian waters.  A  15-­‐year dataset  of  over  80 fish species indicates large fluctuations in recruit   densities among locations, years,species and  within a season. The strength of the East Australian current and associated eddies is a weak  predictor  of  recruitment but  a poor predictor of overwintering success. Overwintering is strongly related to winter temperatures in some species but only weakly in others. Predictions of range shift for these species under climate change are   interpreted in the light of these results.