While some sea snake species eat a wide variety of prey, the spine-tailed sea snake has an extremely specialised diet (7), feeding exclusively on fish eggs (2) (3) (4) (7) (9) (10).
As it does not need to immobilise large, moving prey, the spine-tailed sea snake’s fangs are greatly reduced in size and its venom glands, although functional, are rather small (9) (10). The spine-tailed sea snake’s venom is approximately 40 to 100 times less toxic than that of other sea snake species (10). It is also reluctant to bite, so it is not considered to be dangerous to humans (2).
Species within the Aipysurus genus spend all their lives in the water, never venturing onto land (9). Despite being an air-breathing animal, the spine-tailed sea snake is capable of remaining underwater for up to two hours at a time, before surfacing to breathe again. Its single, elongated lung, which extends for almost the entire length of its body, is highly efficient for gas exchange, and sea snakes are also able to absorb oxygen through their skin when underwater. As in other sea snake species, the spine-tailed sea snake has specialised valves which block off the nostrils while underwater (12).
Living in the marine environment poses several challenges, and as in other sea snake species, the spine-tailed sea snake has a specialised gland under its tongue which enables it to excrete excess salt from its body. Additionally, other marine species such as algae and barnacles often become attached to the sea snake’s skin, a problem which is solved each time the skin is shed, which usually happens once every two to six weeks (12).
Like most species of sea snake, the spine-tailed sea snake is viviparous, meaning that it gives birth to live young rather than laying eggs (4) (12). Mating in sea snakes is a lengthy affair, and the males are unable to disengage from the female until copulation is complete (12). There is little information available on the specific breeding biology of the spine-tailed sea snake (4), but in northern Australia the gestation period is thought to be around six to seven months, with the females giving birth in September, and reproducing every year (12). An average of 4 young are thought to be produced per clutch (4) (12), but in Queensland the spine-tailed sea snake is known to give birth to up to 12 young (12).