Malformations in embryos and neonates of Olive Ridley sea turtle (Lepidochelys olivacea) in Nuevo Vallarta, Nayarit, Mexico

With the aim to know the types of malformations in Olive Ridley sea turtle (Lepidochelys olivacea) embryos and neonates, and determine their prevalence and intensity indexes and chi(2) in Nuevo Vallarta Nayarit, 100 nests were surveyed. From each nest, the total number of eggs and the number of embryos and neonates with any kind of abnormalities were registered. In 21 types of malformations located on seven anatomical regions, three new types were registered: anterior flippers amelia, bifurcated anterior flippers and rinodimo. The carapace presented significantly higher frequency of abnormalities (41.7%), followed by mandibles and general malformations (17.6% each one). The most frecuent type of malformation was the compressed carapace (26.9%), followed by albinism (14.8%) and xiphosis (13.2%). Prevalence (50% on nests and 1.8% on the organisms) and intensity (2.78 malformed organisms per nest and 1.57 malformations per organism) were high medium, compared to previous studies. Sea turtles from Bahia de Banderas may be exposed to anthropogenic contaminants, but is necessary to do long term studies to corroborate this possible relationship.