Leatherback movements and environmental associations varied by oceanographic region, with slow, sinuous, area-restricted search behavior and shorter, shallower dives occurring in cool (median sea surface temperature: 18.4☌), productive (median chlorophyll a: 0.80 mg m −3), shallow (median bathymetry: 57 m) shelf habitat with strong sea surface temperature gradients (median SST gradient: 0.23☌ km −1) at temperate latitudes. From 2007 to 2010, we used satellite telemetry to monitor the movements and dive behavior of nine adult and eleven subadult leatherbacks captured on the Northeast USA shelf and tracked throughout the Northwest Atlantic. Many turtles die from malabsorption and intestinal blockage following the ingestion of balloons and plastic bags which resemble their jellyfish prey.Leatherback sea turtles, Dermochelys coriacea, are highly migratory predators that feed exclusively on gelatinous zooplankton, thus playing a unique role in coastal and pelagic food webs. Pollution, both chemical and physical, can also be fatal. Longline fisheries have also pushed the Pacific subpopulation to the brink of extinction. A reported average of 1,500 mature females were accidentally caught annually in the 1990s. For those that do survive to adulthood many human activities indirectly harm the population.Īs the largest living sea turtles, turtle excluder devices can be ineffective with mature adults. Threats to Survival:Īdult Leatherback Turtles have few natural predators once they mature they are most vulnerable to predation in their early life stages. International – Listed as Critically Endangered (facing an extremely high risk of extinction in the wild in the immediate future) by the International Union for Conservation of Nature and Natural Resources (IUCN). – Listed as Endangered (in danger of extinction within the foreseeable future) under the U.S. Unlike other species of sea turtles, leatherback females may change nesting beaches, though they tend to stay in the same region. Lays an average of 80 fertilized eggs, the size of billiard balls, and 30 smaller, unfertilized eggs, in each nest. Extensive marking from front flippers at the track and extending the total track width to 6 – 7 feetįemale Leatherback Turles may lay as a many as nine clutches within a nesting season (average 4 to 7 times per season), with an average of 10 days between nestings.Ridged track center with a thin, straight, and well defined tail drag mark that is punctuated by tail point marks.
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