EFFECTS OF HURRICANE-ANDREW ON THE SEA-TURTLE NESTING BEACHES OF SOUTH FLORIDA

Because of the close overlap of hurricane season (June-November) and s ea turtle nesting season (March-November) in the Caribbean and Northwe st Atlantic Oceans, hurricanes are a potential cause of damage to sea turtle populations. However, no data has been gathered on either the i mmediate or long term effects of hurricanes on adult sea turtles or th eir nesting beaches. Hurricane Andrew, which struck South Florida on 2 4 August 1992, provided a unique opportunity to quantify the impact of a category 4 hurricane on six Florida nesting beaches. It was determi ned that Hurricane Andrew affected turtle nests over a total of 90 mil es of beaches on the east and west coasts of Florida. We found that th e storm surge associated with the hurricane produced the greatest mort ality through nest flooding. The greatest surge effect was felt on bea ches closest to the ''eye'' of the hurricane, where egg mortality was 100%. In areas farther away from the ''eye,'' the surge was lower and mortality was correspondingly decreased. Detailed data on post-hurrica ne hatching success, mortality, and cause of death was gathered on eig ht relocated and eight in situ nests on Fisher Island in Miami, Florid a, which suffered from flooding and extensive changes in topography. S ixty-nine percent of the eggs did not hatch after Hurricane Andrew and appeared to have drowned during the storm. Further mortality occurred when surviving turtles suffocated in nests situated in the beach zone where sand had accreted. This later mortality may be substantially re duced if beach topography is returned to normal and beach debris remov ed after a hurricane.