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Despite multiple studies examining the diving behavior of leatherback sea turtles (Dermochelys coriacea) at coarse resolution over broad distances, there is still a paucity of high‐resolution diving data collected in areas where foraging has been confirmed. Short‐term (~1–3 h) deployments of suction cup tags with time–depth recorders (TDRs) on 10 free‐swimming leatherback turtles in a foraging area off Nova Scotia, Canada during August and September (2007–2014), captured a total of 161 dives. High‐resolution (1–5 s sampling rate) dive profile data indicated variability in diving behavior between and within individuals. On average, turtles spent 55.7% of their time diving and 44.3% at the surface. Turtles generally performed short (mean duration = 250.4 s [SD = 47.9 s]) and shallow dives (mean depth = 24.3 m [SD = 5.8 m]). We recorded a mean dive descent rate of 0.32 m/s, which is faster than values recorded for leatherbacks in tropical waters. This may reflect differences in environment, behavioral mode (e.g., foraging vs. inter‐nesting), and body condition. Linear mixed‐effects models suggest a significant positive correlation between descent rate and mean depth, maximum depth, and integrated vertical bottom movement (IVBM). Turtles with faster descent rates dove deeper and increased their predicted foraging behavior (IVBM, or the sum of absolute differences in depth changes while at the bottom portion of their dives). Models additionally showed that dive time, bottom time, and IVBM were all positively correlated to the post‐dive surfacing. This suggests that turtles required more time at the surface to recover and/or handle prey following longer dives characterized by increased vertical movement at the bottom portion of the dive. Dives were complex; the application of standard dive type/shape analysis may be over‐simplified and inappropriate for leatherbacks foraging in these habitats. These results portray a novel and detailed look at the foraging dynamics of a diving marine reptile. [ABSTRACT FROM AUTHOR]

Fisheries bycatch is posited to be a leading cause of decline in abundance of Atlantic leatherback turtles (Dermochelys coriacea). However, although this species regularly interacts with fisheries across its range, movements and postrelease survival of leatherbacks remain largely unstudied. Such research is lacking because sampling opportunities are unpredictable and logistically challenging. Here, movements of 4 leatherbacks equipped with satellite tags following incidental capture in fixed-gear fisheries in Nova Scotia, Canada, are presented, alongside results from previous post-entanglement tracking of 15 leatherbacks tagged throughout the Atlantic Ocean. Mean tracking duration after tagging was 232.58 d (standard deviation 165.61; sample size=19), comparable with what has been reported for fishery-independent deployments of satellite tags on leatherbacks. This result indicates that, provided they are released carefully and completely from fishing gear, many leatherbacks survive entanglement events without apparent long-term effects. [ABSTRACT FROM AUTHOR]