ratory Analysis {#sec005}
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Samples for this study were collected between May and November when the pound net fishery is operational. For each sampling event, surface water temperature was recorded to the nearest 0.5°C using calibrated thermometers. Nets were fished and sea turtles retrieved every 3 to 4 days. The entrance/exit to the net remained open throughout deployment and the turtles could feed, swim, and surface to breathe while in the nets. Standard morphometric measurements were obtained from each turtle, including standard straightline carapace length to the nearest 0.1 cm \[[@pone.0115739.ref015]\]. Body weights could not be obtained in the small fishing boats. For each first capture, both rear flippers of each turtle were tagged with external Inconel flipper tags (National Band and Tag Company, Newport, KY) and a single passive internal transponder tag (Destron-Fearing Corp., South St. Paul, MN) was injected into the triceps muscle complex of the turtle's left front flipper. A general physical examination was performed on each turtle and any individuals deemed to be unhealthy (e.g., thin, weak, lethargic, injured, heavy epibiota, external masses) were transported to a rehabilitation center for treatment and excluded from the analyses. With the exception of 2007, laparoscopy was performed on a subset of the turtles for identification of sex during two separate one-week periods in the summer and fall. This technique was used to validate serum testosterone concentrations as a comparatively non-invasive means of identifying sex in juvenile loggerhead sea turtles in different seasons for use in population monitoring and modeling \[[@pone.0115739.ref016]\]. The sex of the remaining individuals was identified by assessing serum testosterone levels when water temperature was ≤ 20°C.

Within 15 minutes of retrieval from the net, venous blood samples were collected from the dorsal cervical sinus into sodium heparin blood tubes (Monoject, Sherwood Medical, St. Louis, 