The effects of beach nourishment on sea turtle nesting densities in Florida

The increasing use of beach nourishment as a method of shoreline stabilization has led to concerns within the sea turtle community about the potential effects of nourishment on sea turtle nesting habitat. Various publications have discussed characteristics of beach nourishment projects that could potentially have an effect on sea turtle nesting habitat, specifically addressing declines in sea turtle nesting on nourished beaches the first year following nourishment. Nesting densities more closely approximate control beach densities by the second year post nourishment, and no significant difference is discernable by the third year post nourishment.;This study hypothesized that nourishment activities generally cause a short-term decline in nesting densities, but that the decline is present for no more than two years. It identified Florida beaches with available, comprehensive beach nourishment and sea turtle nesting data for the past twenty years. Using these data, the study analyzed sea turtle nesting at a regional scale to determine correlations in nesting densities for three years prior and three years following 13 beach nourishment events on ten Florida beaches. This information provided a basis for recommending policies for minimizing declines in sea turtle nesting following beach nourishment projects in the state of Florida.;The analysis of the nesting data showed that approximately six of the nourishment events experienced declines in the first year or two post-nourishment, supporting the hypothesis. The remaining seven beaches did not support the hypothesis. Five of the nourishment events that did not support the hypothesis showed no difference in nesting densities compared to the control beaches, and the remaining two nourishment events experienced increases in nesting when compared to the control beach.;The analysis of these 13 nourishment events indicates that the nesting sea turtles' responses to nourishment vary based on site-specific conditions. When data are available, nourishment projects should evaluate nesting trends following past nourishments at their particular beach to assist in developing an appropriate strategy for preventing declines in nesting. Due to the potential declines in sea turtle densities that may occur following nourishment, coastal managers should consider methods such as retreat to avoid the need for shoreline stabilization projects.