ZUR BRUTBIOLOGIE DER MEERESSCHILDKROTE CARETTA CARRETTA CARETTA L.

Abstract

The spawning localities of Caretta caretta east of Santa Marta/Colombia are wide-open beaches, on the average 25 to 30 m wide and ascending with a straight or smoothly sloping gradient up to the belt of vegetation. No dunes are being formed. A strong surf is present along the coastline all the year. The population of Caretta has markedly decreased due to intensive trapping. The average size of females coming to shore has similarly decreased relative to other populations in the Caribbean. The breeding period extends from midapril to mid-august. About 300 nesting holes are layed out along the 7,5 km of spawning beach during this time. The nesting proceeding of Caretta is described in detail and the nesting behaviour of sea turtles discussed. Nest building takes about 20 minutes, deposition of eggs about 15 minutes, and the covering of the nest hole about 20 minutes. The time on land of a female Caretta from the moment of emergence from the sea up to the time of return to the sea is somewhat more than 60 minutes. The spawn comprises on the average 106 eggs. The mean maximum egg diameter is 43,3 mm, and the mean egg weight 38,4 g. The eggs are deposited individually or in groups of two, three, four or five each.