Sea snakes

Redsted Rasmussen, A. (Foredragsholder)

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Beskrivelse

The most typical feature of a sea snake is the vertically flattened paddle-like tail, which is not found in any other terrestrial or aquatic snakes. Sea snakes occur in the tropical and subtropical waters of the Indian and Pacific Oceans from the east coast of Africa to the Gulf of Panama. Most species are concentrated in the Indo-Malayan Archipelago, South China Sea, Indonesia and the Australian region. Sea snakes inhabit shallow waters along coasts and around islands, river mouths and up rivers and have also been found in lakes. Identifying sea snakes to species level is very difficult; especially the genus Hydrophis shows great intraspecific variation making it difficult to use only external characters for their identification. Most sea snake species feed on fish that are close to the bottom or sedentary; a few prefer fish eggs (Aipysurus eydouxii, and the genus Emydocephalus). Using Laticauda to capture undescribed eel species has been shown to be very effective because the eels are extremely secretive in their habits giving no chance to collect them using traditional methods.
Many of the more than 60 species of sea snakes have a broad distribution in both the Indian Ocean and the Pacific Ocean and are abundant in these areas. Other species are much less well known and some species are only collected from very restricted areas and therefore much more vulnerable for change in the environments. Hydrophis laboutei is a recently described species which is only known from two specimens collected at Chesterfield Reefs (New Caledonia). Species with a limited distribution is therefore, highly vulnerable to all kinds of environmental changes, including Aipysurus fuscus, A. apraefrontalis and A. foliosquama which have only been collected in the north west part of Australian. Recent surveys show that there has been a drastic decline of specimens in one of this area (Ashmore Reef) over the last 20 years.
Periode22 jan. 2020
Sted for afholdelseWestern Australian Museum, Australien
Grad af anerkendelseInternational