Theoretical and empirical studies on the evolution of capital vs. One fundamental dichotomy in reproductive behavior is between species that fuel reproduction with recently acquired energy (“income breeders”) and those that rely on stored energy reserves (“capital breeders,” Drent and Daan, 1980). To cope with limiting and/or fluctuating food resources, for example, organisms have evolved a wide range of behavioral strategies to acquire energy and allocate this to reproduction. Across a variety of taxa, variation in environmental characteristics such as food availability or climate conditions can have dramatic repercussions on reproductive traits such as clutch size or reproductive frequency (e.g., Seigel and Fitch, 1985 Lourdais et al., 2002 Wallace et al., 2007). Reproductive performance is affected ecologically and physiologically by physical environmental factors. The behavioral tactics (dive patterns) they use, however, differ because of bathymetric constraints. Croix) suggests that gravid leatherback turtles in all regions except French Guiana assume an energy-saving strategy during the internesting interval that involves gliding to or resting on the sea floor in colder water. Comparison with the dive behavior in other regions (Costa Rica, French Guiana, Grenada, Malaysia, and St. Fine-scale monitoring (1-s interval, 0.5 m of resolution) suggested that these routine deep dives were not accompanied with any wiggles (up-and-down undulations in the depth profile) or flat-bottom phases, and they reached deep waters by gliding, which suggests that these dives may have served to conserve energy and/or to thermoregulate. The continuous dive data showed that turtles spent 37.3% of their time in routine deep dives and that they stayed in cold waters below the thermocline. All dive data demonstrated that the leatherback turtles routinely dove to deep waters (around 150 m) throughout the internesting interval. We used three types of dive data: time-at-depth data (Papua Barat: N = 4 Solomon Islands: N = 6), intermittent dive data (Papua Barat: N = 6) obtained from ARGOS satellite transmitters, and continuous dive data obtained from recovered semi-archival tags (Papua Barat: N = 1, Solomon Islands: N = 1). The dive behavior of gravid leatherback turtles ( Dermochelys coriacea) was studied during the internesting interval in two western Pacific nesting regions: Papua Barat, Indonesia, and the Solomon Islands in 2006, 2007, and 2010. 3Marine Mammal and Turtle Division, Southwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, Moss Landing, CA, USA.2Research Center for Subtropical Fisheries, Seikai National Fisheries Research Institute, Fisheries Research Agency, Ishigaki, Japan.
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