Zimmerman and Heatwole (1990) found evidence of photoreceptors in the tail of Aipysurus laevis and suggested that light sensitivity of the tail, combined with the more familiar light sensitivity of the eyes at the front end, helps the snake know when it is adequately concealed.
As is the case for many snakes, the growth rate of sexually mature olive sea snakes is markedly slower than for immature individuals (Burns and Heatwole 2000). Males become sexually mature at about 3 years of age while females mature at 4-5 years (Burns and Heatwole 2000).
The olive sea snake (Aipysurus laevis) is the most common sea snake on the reefs of eastern Australia (Burns and Heatwole 1998). This species is widely distributed in Australasian waters, occurring on the coral reefs of Australia from Brisbane on the east coast all the way around to Shark Bay on the west coast, as well as New Guinea, and the Coral Sea.
Burns and Heatwole (1998) estimated the home range of Aipysurus laevis on the Great Barrier Reef to be around 1500 m2 (relatively low for snakes in general) and the maximum overlap of neighboring home ranges in their study was nearly 90%. When not foraging or surfacing to breathe, snakes hide under any convenient cover rather than returning repeatedly to the same shelter. Foraging is concentrated at the interface of coral or rock with sand and occurs both during the day and at night.
Olive sea snakes live to about 15 years or older (Burns and Heatwole 2000).
Aipysurus laevis is the largest member of its genus. It is typically about a meter in length, although it can exceed two meters. Its fangs may be 7 mm long. The tails of sea snakes are flat and paddle-like. It is distinguished from congeners by the combination of having 21 or 23 mid-body scale rows, fewer than 180 ventral scales, at least the parietal shields on the head fragmented, and ventral scales which are not (or scarcely) notched on the rear edge (Gopalakrishnakone 1994).
Very small olive sea snakes are infrequently encountered. This may be due to a combination of factors, possibly including low reproduction rate, high juvenile mortality, and biased sampling (Burns 1984, cited in Heatwole 1997).
Despite possessing a potent venom, olive sea snakes are nevertheless subject to predation, notably by sharks and ospreys (Heatwole 1975, cited in Zimmerman and Heatwole 1990).
From Burns 1985 (as cited in Heatwole 1997): In the Great Barrier Reef, olive sea snakes ovulate in the southern spring (October). Embryonic development takes about 6 months and young are born in the southern autumn (April). Individual females probably breed only every other year. Olive sea snakes bear live young underwater. Average brood size is just 2.6.
The olive tree snake (Aipysurus laevis) is generally docile and usually appears merely curious if approached by a human diver. During the breeding season (May-July), however, attacks on humans are more frequent (Heatwole 1975, cited in Gopalakrishnakone 1994). A full neoprene wetsuit, however, should offer adequate protection from all but the largest individuals (Heatwole 1975, cited in Gopalakrishnakone 1994).
The olive sea snake (Aipysurus laevis) is a generalized predator, with a known diet including representatives of at at least 12 families of fishes, as well as fish eggs and shrimp, crabs, and molluscs (Voris and Voris 1983). Fish species vary substantially in their sensitivity to olive sea snake venom. Patterns of sensitivity in experiments with several eel species (potential prey) led Heatwole and Poran (1995) to argue that potential prey species most likely to encounter olive sea snakes are actually less vulnerable to olive sea snake predation. They suggest that species that are sympatric (i.e., overlapping in geographic range), syntopic (i.e., overlapping in habitat within that geographic range), and most likely to interact with the olive sea snake have evolved some resistance to olive sea snake venom.
