Distribución de la culebra de mar Pelamis platurus en el pacífico mexicano

The yellow-bellied sea snake is the wider in distribution whiting the marine ophidians, occurring in the tropical and subtropical Pelamis platurus seas, from the east coast of Africa through the Indian and Pacific oceans to the Pacific Coast of the Americas. lt is possible to notice that Pelamis in the Pacific of Mexico, occurs mainly in tropical warm waters but also in the cold waters of the California Current and the most northem portion of the Gulf of California (cold at least in winter months). The question at this point is how can be explained those records of the snake in cold waters. The limiting factors for the distribution of this species are: the annual variation of the sea surface temperature and the depth of the water, the prevalent current and the pattem of storms, restricting the species to the water isotherm of 26º C, in correlation to the isobath of 100 m depth. As a function of the limiting factors it has been established the existence of resident populations capable of reproduce it selves, and the existence of waif individuals or populations in extreme ecological conditions for the survival of the species. The locality records of the species were analized, and it is observed that there are records of the species for all the Mexican states at the Pacific Coast of Mexico and the Gulf of California. Jalisco and Guerrero are the Mexican States showing the larger number of records. There are just a few records from the states of Baja Califorma, Baja Califorma Sur and Sonora. By analyzing the collecting dates, it was found that iii the region between Baja California and Jalisco, 67% of the records are from winter (January to April) and just 33% from the rest of the year. Most of the collecting dates (74%) between Colima and Chiapas, are from the warmer months of the year (May to December) and 26% from-the winter months at this latitude. It is possible that the specimens collected at larger latitudes reflect waif populations or individuals, carried accidentally by the North Pacific Current from some place in the north Pacific and located at those places as non resident individuals in extreme survival conditions. Most of the records analyzed belong to beached individuals, many of theme from the coasts between Jalisco and Oaxaca in almost every month of the year, but particularly in spring and The beached specimens may be were related also to storms, and dominant and intense winds that thrown the snakes toward the beach