INGESTION OF MARINE DEBRIS BY JUVENILE SEA-TURTLES IN COASTAL FLORIDAHABITATS

Digestive tracts from 51 sea turtle carcasses that washed ashore on th e east and west coasts of Florida were examined for the presence of an thropogenic debris. Debris was found in 24 of 43 green turtles (Chelon ia mydas), 0 of 7 Kemp's ridleys (Lepidochelys kempi), and 1 of 1 logg erhead (Caretta caretta). Ingested debris included plastic, monofilame nt line, fish hooks, rubber, aluminium foil, and tar. For green turtle s, ingestion of debris was not significantly affected by location of s tranding, season, or body size. Debris ingestion was significantly aff ected by sex of the turtle. Frequency of occurrence of debris was sign ificantly higher in females, but differences in the mass or volume of ingested debris were not significantly different between the sexes. Al though frequency of occurrence of debris was high in green turtles (56 %), the mass and volume of the debris were small-mean 0.52% of wet mas s of gut contents and mean 0.72% of the volume of gut contents, respec tively. However, small quantities of debris can kill sea turtles; the death of at least two turtles in this study resulted from debris inges tion. The debris in the two turtles represented 4.6% and 5.8% of wet m ass and 3.2% and 9.8% of volume of the gut contents, respectively. In both turtles, the debris represented inflated percentages because the turtles had not been feeding normally prior to death because the debri s affected gut function. Sublethal effects of debris ingestion (e.g. a bsorption of toxins) has an unknown-but potentially great-negative eff ect on the demography of sea turtles.