Application of TOPEX-POSEIDON satellite altimetry to simulate transport dynamics of larvae of spiny lobster, Panulirus marginatus in the NorthwesternHawaiian Islands, 1993-1996

A commercially valuable trap fishery for spiny lobster (Panulirus marginatu s) has existed in the Northwestern Hawaiian Islands since the late 1970s. F isheries landings and research trapping show that spawning biomass and recr uitment to the fishery collapsed in 1990 in the northern portion of the fis hing ground and that there has been no recovery to the present, although re cruitment remained strong at banks 670 km to the southeast. An advection-di ffusion model is used to investigate larval transport dynamics between thes e two regions. The movement model is driven by geostrophic currents compute d every 10 days from sea surface height obtained from TOPEX-POSEIDON satell ite altimetry. The larval transport simulations indicate that even though l arvae have a pelagic period of 12 months. banks differ substantially in the proportion of larvae they retain from resident spawners as well as the pro portion of larvae they receive from other banks. In particular, recruitment to the northern portion of the fishing grounds is weak due to a very low l ocal spawning biomass and a very limited contribution of larvae from the ar ea of strong recruitment and high spawning biomass in the southeast. The re sults also suggest that satellite altimetry can provide useful information on physical dynamics for recruitment studies.