Prevalence of visible injuries to leatherback sea turtles Dermochelys coriacea in the northwest Atlantic

Standardized external injury assessments were used to investigate the relative importance of direct anthropogenic and natural threats to northwest Atlantic leatherback turtles (Dermochelys coriacea). The information was used to assess whether the susceptibility to these threats varies between low latitude nesting and high latitude foraging region, by size and sex. Leatherback turtles foraging off the coast of Nova Scotia and at nesting sites in Trinidad were sampled. Combined, 62% showed characteristic marking associated with one injury. No significant differences in injury rate or type between regions, sexes or sizes were found. The proportion of turtles showing injuries suspected to be of anthropogenic origin (34%) was significantly higher than those thought to be associated with predatory behavior (16%). Entanglement with rope was thought to occur in 19% of the injuries and 17% from hooks. This population of leatherback turtles faces potentially common widespread threats from predation and fishing gear across its range.