The Banded Sea Krait, or Laticauda colubrina, is best known for its potent venom and striking bands around its body. This small, semi-aquatic sea krait is found in the Indo-Pacific tropical waters, often in or near the coral reefs off of small islands.
This species has several common names, including Colubrine Sea Krait, Yellow-lipped Sea Krait, or Banded Sea Snake. In spite of their powerful venom, they are also known for their docile behavior.
This species is commonly called the Yellow-lipped Sea Krait due to its yellow snout and face. The bands referenced in its name are black and number between 20 and 65, spanning their entire body. The body itself varies in color – from creamy, to grey, to blue. The cylindrical body shape is smaller in males and larger in females, creating sexual dimorphism. Males reach up to three feet, and females reach up to four and a half feet. This small sea snake ranges from one to four pounds. This species has a long tail with a paddle-like shape, making it well-adapted for swimming.
The carnivorous Banded Sea Krait is adapted to feed on prey much larger than itself. First, they use their venomous fangs to inject their prey into paralysis; then, their extraordinarily wide jaws consume them whole. This snake almost primarily eats eels. The females are known to dive to deeper depths to catch and eat larger Conger Eels, often three times their own body size. The males are known to hunt in shallower water and feed upon smaller moray eels.
Aside from eels, this sea snake is known to hunt and corral small fish. They use their small heads and have been known to hunt with their own species, Giant Trevally and Goatfish. They work together to chase smaller fish out of the small crevices among the coral reefs. The sea snakes eat the smaller fish, and their hunting partners eat the larger fish.
The Banded Sea Krait population originated in Papua New Guinea and has become widespread throughout Asia, the Philippines, India, the western Pacific islands, New Zealand, the Indian Ocean, and parts of Japan. The species prefers to stay close to rocky coral reefs near the shoreline. Juveniles stay closer to shore, but as they age, they utilize the deeper and more open waters of their range, using the movements of their paddle-like tail to help them swim and maneuver in the small crevices while hunting or resting.
This small sea snake spends most of its time in the water but is known to be semiaquatic, spending some of its time on land. Adult males hunt in shallow water, typically closer to the shore. Adult females are larger and better adapted to hunt in much deeper water, up to almost 200 feet, giving them a wider hunting range. The males and females have a unique characteristic of returning to land after hunting to digest their food in the sand or near the rocky shores.
The Banded Sea Krait mates during the warmer months of September through December. This species has a polyandrous mating behavior, meaning the females have more than one partner during the breeding season. During this season, males will gather in groups either on land or very near shore, awaiting a female. It is believed that the female releases a pheromone to alert her presence and willingness to breed. Once she is detected, courtship begins with males chasing a single female, intertwining with her in competition.
Once breeding has taken place, the female with lay a clutch of about 10 eggs, returning to land to nest her eggs in crevices along the shoreline. This Sea Krait is oviparous, meaning the eggs are laid, development happens outside the mother’s body, then they hatch later. After an incubation period of four months, the juvenile Kraits then make their way to the shallow waters of the coral islands and shores.
The Banded Sea Krait has a special adaptation called a saccular lung, a special extension of the lungs to allow for expanded capacity. They use this feature while hunting for eels, allowing them to dive to almost 200 feet.
On land, these sea snakes are skilled tree climbers, especially in mangrove areas. They have been found up to 130 feet high in the trees.
This species also has a behavior called philopatry, where, like sea turtles, they return to the same beach year after year to breed, lay eggs, digest their prey, and rest.
The Banded Sea Krait is susceptible to habitat loss of their aquatic coral reefs and terrestrial lands they use to live and breed. In some places in the Philippines, the species is hunted for its skin and meat. The list of ocean and land predators is short due to their highly toxic venom. They are eaten by sharks and larger fish while they are hunting and are vulnerable themselves. They are also prey items for birds while on land and sea eagles while in the ocean.
What eats the Banded Sea Krait?
Due to its venomous nature, this species does not have many predators. However, it is vulnerable while it is hunting because its head is buried in small crevices. During this time, sharks and larger fish predate on the Banded Sea Krait.
What happens if a Banded Sea Krait bites you?
The Banded Sea Krait bite contains a powerful neurotoxin that can deliver a lethal dose. The venomous bite can cause lethargy, convulsions, and paralysis.
Are Banded Sea Kraits aggressive?
Despite its highly toxic venom, the Banded Sea Krait is incredibly docile, even known to not bite when being threatened or attacked.
What is the difference between a sea krait and a sea snake?
While the Banded Sea Krait, along with all sea kraits, are considered sea snakes, there are some differences. Sea kraits are amphibious, in that they live part of their lives in the water and part of their lives on land. Unlike sea snakes, sea kraits move onto land to digest, lay their eggs, and drink fresh water. One other difference is the tail; sea kraits have a paddle-shaped tail that allows them to propel themselves through the water when swimming.
Do Banded Sea Kraits drink water?
Yes, like most species of sea kraits, the Banded Sea Krait drinks fresh water while on land and even from the surface of the ocean after rainfall. This makes this species of sea snake highly susceptible to drought and climate change in its habitats.