While the Osa Peninsula, rich with biodiversity and sheer beauty, is a wonderful place to kick back and relax, there are numerous opportunities for visitors to catch a glimpse of some of the world's most fascinating reptiles. Some of which, like the Terciopelo, can be especially hard (and dangerous) to spot. The Terciopelo is a beautiful dark grey, brown or olive green snake, with a dorsal pattern of triangular designs on both sides of its body, resembling a letter 'X' visible from above. It’s a large snake that can grow up to 250 cm (over eight feet!) in length, although the average adult is between 140 and 180 cm (4.6 to 5.9 ft) long. The females are much longer than the males. It principally eats small mammals and birds. The species is viviparous, which means that the embryos grow inside of the mother and are born fully formed. Furthermore, the snake is very fruitful; it can give birth to up to 90 offspring. This high fertility explains in part why the Terciopelo is one of the most abundant snakes in Costa Rica.