Reptiles

Marine reptiles

The only marine reptiles present in the study area are the Yellow-bellied Sea Snake (Pelamis platurus), (an extremely venomous reptile) and several species of sea turtles. By far the most abundant species of those is the Olive Ridley Sea Turtle (Lepidochelys olivacea), which visits long sandy beaches of the bay to deposit its eggs. Thanks to an extensive effort by many volunteers, the population of Olive Ridley Sea Turtle seems to be stabilizing. On the other hand, numbers of other sea turtle species, such as the Leatherback (Dermochelys coriacea), have been continuously declining. Sea turtles are the only migratory reptiles in the study area.

Forest reptiles

Most species of reptiles are tied to forested areas. Many of them prefer forested areas adjacent to water sources. A good example is the Green Iguana (Iguana iguana), which favors perches overhanging water, or the Brown Basilisk (Basiliscus vittatus), which is found almost exclusively near water.

Many reptiles inhabiting tropical forest are arboreal. Ground species tend to have very effective cryptic coloration, and an ability to lie motionless when waiting for prey or when stalked by a predator. This makes some venomous snake species potentially dangerous, as they can be easily overlooked.

How to find reptiles

When visiting a tropical destination, we tend to expect to see it teeming with reptile life. While the number of reptile species is definitely high in tropical regions (and Western Mexico is no exception), the average visitor might not see as many reptiles as they expect. Apart from the highly visible and abundant species—such as the Green Iguana (Iguana iguana) and the Black Iguana (Ctenosaura pectinata), which are commonly found even within the urban areas quite reliably on their favorite perches— reptiles might take quite an effort to discover. Diurnal lizard species can also be observed quite readily, scurrying around in the undergrowth, on tree trunks and stone walls. Nocturnal lizard species, such as the four- clawed Gecko (Gehyra mutilata), can be found on sections of walls and ceilings close to a light source, which attracts their prey—insects. Most snake species prefer to move during night hours. finding snakes in their natural environment requires experience, knowledge of their ecology, and luck. The best time to see snakes in the study area is wet and warm summer nights. Pick a small paved road with little traffic, preferably a section surrounded by vegetation, and drive slowly using high beams. Take extreme care not to run over a crossing animal. When you spot a snake, pull over to avoid being hit by a car, and use a flashlight to inspect the animal from a distance. Be advised – many species of snakes inhabiting the study area are extremely venomous. Do not approach or handle any snake unless you are a professional with years of snake- handling experience.