Physiological effects of capturing Kemp's ridley sea turtles, Lepidochelys kempii, in entanglement nets
Blood samples were collected from 58 wild Kemp's ridley sea turtles (Lepidochelys kempii) to examine the physiological effects of capture in entanglement nets. Captured turtles were placed in holding tanks or in-water cages to examine whether the postcapture holding protocol influenced the time course of recovery of blood homeostasis. Lactate concentrations at capture were 4.5 ± 0.3 and 3.5 ± 0.3 mmol/L (mean ± SE) for L. kempii assigned to the in-water-cage and holding-tank treatments, respectively. Turtles held in holding tanks for 1 h exhibited a significant increase in lactate concentration over capture levels, whereas lactate concentrations in the cage-held animals did not change. Lactate concentrations declined to less than 1.0 mmol/L by 6 and 10 h post capture for turtles in the in-water-cage and holding-tank treatments, respectively. Plasma norepinephrine (NE) and epinephrine (E) concentrations at capture were substantially elevated above base-line levels reported in the literature for comparably sized loggerhead sea turtles (Caretta caretta). Turtles in holding tanks exhibited greater reductions in NE and E at 1 h post capture than did their counterparts in the in-water cages. Although plasma Na+ and Cl- concentrations were not affected by entanglement netting, K+ concentration was elevated in tank-held L. kempii at 1 h post capture. Taken together, these data indicate that entanglement netting causes significant physiological disturbance in sea turtles and that recovery of blood homeostasis is influenced by the postcapture holding protocol.