Also known as the yellow-bellied sea snake, the pelagis sea snake is one of the most abundant sea snakes in the world. It can be identified by its bright yellow belly; the dorsal region of the snake is black. For migrating, pelagis snakes catch ocean currents rather than using their paddle-like tails to propel themselves through the water. The primary reason these snakes migrate is because the currents take them places in the oceans known as drift lines, or areas where converging ocean currents meet and create still water. Fish are abundant in drift lines, which supplies food for the sea snake.
Water temperature is the primary reason sea snakes do not migrate far from their homes. While some sea snakes venture out several miles away from land, most sea snakes live in warmer, shallow waters near coastal areas. However, they try to avoid being washed up on shore since most species are not able to move on land. No snakes live in the Atlantic Ocean or Arctic Ocean since those waters are too cold. The Indian Ocean near Australia and bays through Southeast Asia are the primary dwelling places of sea snakes. Two sea snakes, the yellow-bellied sea snake and yellow-lipped sea krait (Laticauda colubrina), live in the eastern Pacific Ocean near the Americas.
Another reason sea snakes do not have massive migration patterns is they are air-breathing animals. Sea snakes lack the gills required for breathing underwater. Although sea snakes are able to stay underwater for hours at a time, these reptiles must rise to the surface to inhale much-need oxygen. While underwater, valves cover the sea snake's nostrils to prevent water from entering its body. However, snakes are able to swim quickly over short distances due to their paddle-like tails, which act as a propellers. When swimming, sea snakes move similarly to terrestrial snakes in a "S-shaped" movement.
Some sea snakes, particularly the yellow-bellied sea snake, migrate in ocean currents to find mates. Large populations of sea snakes gather in drift lines to find potential mates, which is easier to find in centralized locations rather than in the open water. Most sea snakes are oviparous, or egg-laying animals, but some species -- particularly the yellow-bellied sea snake -- give live birth. All sea snake reproduction -- egg-laying and live birth -- occurs in the water.