Paresis as a limiting factor in the reproductive efficiency of a nesting colony of Lepidochelys olivacea (Eschscholtz, 1829) in La Escobilla beach, Oaxaca, Mexico

Abstract

Rear flippers are crucial in the nesting process of Olive Ridley Turtles Lepidochelys olivacea, so any impact on them could constitute a limiting factor in reproductive efficiency. Muscle weakness of the rear legs has been observed in some nesting females on La Escobilla beach in Oaxaca state, Mexico; however, this disorder has not been sufficiently researched. The aim of this study was to identify and describe this problem in a nesting colony of L. olivacea in La Escobilla. We obtained the biochemical profiles of eight females with clinical signs of muscle weakness of the rear legs, that could not build the incubation chamber for their nest. In order to compare their blood characteristics, we selected eight seemingly healthy turtles that successfully built their nests, laid eggs through oviposition and covered the nest. We found no significant differences in most of the blood parameters, except for Creatinine-Kinase (CK). Female turtles with muscle weakness presented significantly higher concentrations of CK (t = 2.1448, d.f. = 2, P <0.0001) when compared to the healthy turtles. CK is an appropriate enzyme for identifying the integrity of the muscle cell and is a muscle damage indicator. Our hypothesis is that the paresis observed in the rear legs of the female turtles in La Escobilla could be a chronic debilitation caused by a gradual exposure to biotoxins such as saxitoxins.