Laticauda colubrine has a few different common names including the Banded Sea Krait, Banded Sea Snake, Colubrine Sea Krait, and the yellow-lipped sea krait. They are easily identifiable by their distinct black bands encircling their light blue-greyish under-colour and yellow snout. Females are typically larger and can grow to around 150 cm in length, whilst the males only grow to around 100 cm; however, there have been reported sightings of Sea Snakes reaching a staggering 360 cm!
Unlike many species of sea snakes, the Banded Sea Snake have adapted and developed for a very amphibious lifestyle. They have also developed a salt gland under the tongue giving them the ability to expel excess salt absorbed from the marine environment. Their lungs are also proportionally larger than than lang snakes to allow Sea Snakes to stay underwater for 15 – 30 mins, up to a maximum of 2 hours! Although they are cylindrical in shape like most snake species, they have evolved with a compact, flat tail, a little bit like an oar, giving them the necessary propulsion for aquatic hunting. Common prey includes eels and small fish, and groups of Krait will often be seen working with parties of other predatory fish to capture their prey. Krait also have a unique defensive ability to fool potential predators into believing their tail is in fact their head when searching inside cracks and crevices.
Banded Sea Snakes are air breathing reptiles and return to land around every 10 days for digestion, mating, and the shedding of their skin. There are still some disagreements of how much time they spend on land compared to in the ocean due to the difficulty of accurately researching amphibious species.
Although known for their venomous bite, which is 10 times as toxic as the rattle snakes, the number of recorded attacks is very low and the Banded Sea Snake is considered a very timid and docile animal, typically not aggressive unless dangerously threatened. Most venomous encounters actually occur on trawlers vessels whilst fishing as snakes get caught in the nets, and fishermen are occasionally bitten while releasing them. If bitten, envenomations (injection of the venom) is still very unlikely because venom stocks are complex to produce and are reserved for catching prey; therefore defensive bites are usually not venomous. In addition, a Krait can only open it’s mouth a very small distance and their fangs are extremely small, meaning they are almost of no threat to humans. If however, a venomous bite does occur, severe pain may be felt at the site of the puncture, respiration may weaken, and muscles may contract or cramp. A severe reaction may result in respiratory or cardiac failure and a need for emergency treatment and CPR. First aid includes washing the wound and applying a broad ligature between the injury and the body to slow the spread of the venom. Medical assistance should be called as soon as possible!
At the moment, Banded Sea Snakes are not listed as a threatened species and there is very little work to be done in terms of protection and conservation. However, as fishing has rapidly grown worldwide and specifically in and around Thailand, it is estimated around 80 tonnes of different sea snakes are being caught intentionally or as by-catch every year. These snakes are often exported to other parts of Asia, commonly China and Vietnam, where they are consumed and considered a delicacy, used in medicines, or used to produce snakeskin leather goods.
The Banded Sea Krait is the only Sea Snake found around Koh Tao, and they are truly fascinating to find underwater. They can be found at many of our dives sites and are often spotted on shallower dive down to around 10 m depth. Keep an eye out on your next dive!