Flipper tagging with archival data recorders for short-term assessment of diving in nesting female turtles

摘要

ABSTRACT: Archival data recorders (ADRs) were deployed on nesting female leatherback turtles Dermochelys coriacea to record short-term diving behavior. Plastic cattle ear tags were used as a platform to which an archival depth recorder was attached. The tags were applied to the hind flippers of 10 turtles, ranging from 141.9 to 160.6 cm in curved carapace length at Sandy Point National Wildlife Refuge, St. Croix, US Virgin Islands. We later retrieved 7 of the original 10 tags at the beach; durations of deployment ranged from 22 to 90 h. The recorded number of dives per deployment ranged from 118 to 310. Maximum dive depths ranged from 175.6 to 479.7 m (mean 275.4, SE 41.7, n = 7), and maximum dive durations ranged from 16.3 to 27.8 min (mean 21.3, SE = 1.5, n = 7). Dive data indicated that post-nesting females dove deeper, less frequently, and longer than pre-nesting females—depth: mean _post 78.6 m, 95% CI (56.0, 101.2) versus mean _pre 45.4 m, 95% CI (37.1, 53.8); frequency: mean _post 2.4 dives h–1, 95% CI (1.8, 2.9) versus mean _pre 5.4 dives h–1, 95% CI (5.0, 5.8); duration: mean _post 13.1 min, 95% CI (11.2, 15.1) versus mean _pre 6.1 min, 95% CI (5.5, 6.6). A pre-nesting female was defined as one that attempted to nest but returned to the sea without laying eggs. This ADR deployment method provides a simpler and less intrusive alternative to other tag attachment methods, such as harness and tethers, when the research questions require only short deployment time of archival recorders.