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See discussions, stats, and author profiles for this publication at: https://www.researchgate.net/publication/280733616 Guide to the Sea Snakes of the Kimberley Coast of Western Australia Technical Report · August 2015 DOI: 10.13140/RG.2.1.2701.2960 CITATION READS 1 1,303 2 authors: Ruchira Somaweera Kate Laura Sanders The Commonwealth Scientific and Industrial Research Organisation University of Adelaide 67 PUBLICATIONS 1,256 CITATIONS 91 PUBLICATIONS 2,651 CITATIONS SEE PROFILE SEE PROFILE Some of the authors of this publication are also working on these related projects: Global genetic structure in the widest-ranging squamate View project Sensory role of scale sensilla in squamates View project All content following this page was uploaded by Ruchira Somaweera on 06 August 2015. The user has requested enhancement of the downloaded file. Life in the ocean Sea snake bites We are not sea snakes Being entirely aquatic, sea snakes show remarkable adaptations to a life in water: As a general rule all sea snakes must be regarded as dangerously venomous and handled • A vertically flattened paddle-like tail for propulsion (absent in all other snakes, including with great caution. Some species are inoffensive and only bite under provocation, but Several species of eels closely resemble sea snakes in color freshwater and brackishwater species). other species are much quicker to defend themselves when threatened. Sea snakes are pattern and body shape. For this reason, people often confuse • Dorsally positioned nostrils each with a valve that closes when they dive. quite curious creatures and sometimes approach people in the water. Avoid interacting the two. Here’s how to tell them apart: with the snake if one approaches you and wait patiently until it moves off. • Salt regulating glands (specialised excretory glands on the base of the tongue). 1. Eels have a scaleless, mucus-coated skin. The heads • A single lung that extends nearly the full length of the body, and a special ability to It is important to know that all species carry potent venom and bites could be fatal if and bodies of snakes are covered in scales, although the body absorb oxygen through the skin. untreated. The people at most risk in getting bitten are commerical and recreational scales of some sea snakes are very small. fishers handling nets. 2. As most other fish do, eels have gills (either circular of Biology slit-shaped). Sea snakes on the other hand are reptiles with lungs In case of a sea snake bite Feeding so don’t have visible gill openings on the head. • Wrap a ‘pressure bandage’ (e.g. a broad crepe bandage) around the limb starting at While some sea snakes, such as the Olive Sea Snake, have generalist diets, most have highly 3. Most eels have fins located along the top or bottom of the the fingers or toes and wrap toward the body. It should be tight but the fingers and toes specialised preferences, feeding almost entirely on eels, gobies or catfish-like prey. Three fishes’ body,y, or pprotrudingrotrudin from just behind the head. All sea should remain pink so that the circulation is not cut off (this is not supposed to be a snakeses hhaveave a flattened pappaddle-shapedd tail, but none have fins. species, including the Turtle-headed Sea Snake, specialise on fish eggs and have tourniquet) bending at the joints. accordingly reduced their venom systems.ms. There are also records of some sea snakes • Apply a rigid object as a splint and bind it firmly to as much of the limb as possible. Banded Snake Eels (Myrichthys colubrinus) eating crabs, shrimps, sea snails and squid.d. closely resemble sea snakes • Keep the patient as still, calm, warm and comfortable as possible. • Call for proper medical treatment as quickly as possible. Estuaries, mangroves and mudflats of the Kimberley region are also inhabited by Guide to the Sea Snakes of the ‘Mud snakes’ of the family Homalopsidae. Did you know.. Threats to sea snakes in the region These are live-bearing, aquatic snakes that Head Kimberley Coast of Western Australia Many sea snakes have low dispersal rates, restricted forage on fish and crustaceans. Mud While most sea snakes distributions and specialist habitat preferences. In northwest snakes have fangs at the back of the Australia, marine habitats are potentially threatened by upper jaws and are not highly venomous, Text and design by Ruchira Somaweera & Kate Sanders grow to around one metre in length, some infrastructure developments and associated dredging whereas all sea snakes have fangs at the projects, as well as climate change-related rising sea front of their upper jaws. Unlike the Species such as the species that prey on paddle-shaped tails of sea snakes, the tails Slender Sea Snake (Microcephalophis gracilis)* large eels reach close temperatures. Being sensitive to low frequency vibrations, sea of mud snakes are tapering to a point. Of the 10,000 different species of living reptiles, only about 60 species of that specialise on burrowing eel prey have evolved tiny to three metres.. snakes might also be vulnerable to anthropogenic noise live-bearing ‘true’ sea snakes are fully adapted to a life in salt water. All other A Stokes’ Sea Snake (Hydrophis stokesii) heads and thin forebodies for probing burrows (shipping, seismic air guns, pile driving). feeding marine reptiles, including the sea kraits (a group of ocean-going snakes that [* species not found in the Kimberley] The Australian Bockadam (Cerberus australis) (L) and the White-bellied Mangrove Snake (Fordonia leucobalia) A few of the (R) are common mud snakes along the Kimberley coast. The body colour of these species varies largely from evolved separately), sea turtles and the saltwater crocodile, must leave Breeding world’s sea snakes are brown to grey to red the water to lay eggs on land. In Australia, up to several All sea snakes give birth to live young in the water, with typical numbers of young per clutch actually freshwater species and inhabit thousand sea snakes get Sea snakes originated in Australian waters and have since colonised the tropical ranging from 3 in Leaf-scaled and Mosaic Sea Snakes to more than 10 in Spine-bellied and collected as by-catch in the Elegant Sea Snakes. Although not found in Kimberley waters, sea kraits are amphibious lakes in Thailand, What you can do and subtropical waters of the Indian and Pacific Oceans. Most species are found Cambodia, the trawler fishing industry each in shallow waters along coasts, in inshore habitats, and around islands and coral snakes that lay eggs on land but no known nesting populations exist in Australia. year. Being air-breathers, If you see a live or a dead sea snake… Philippines, and reefs. An exception is the Yellow-bellied Sea Snake (Hydrophis platurus) that lives Solomon Islands.. sea snakes often drown and • Use the key in this booklet to identify down to species or as close as possible if it in the open oceans and has the largest distribution of any snake. Behaviour die in the nets. can be done safely. Although sea snakes are able to absorb a portion of their oxygen requirements from sea The Olive Sea • Take a clear photograph if possible . water through the skin, all sea snakes are air-breathers and therefore need to surface to Kimberley coast and sea snakes Snake (Aipysurus • Report your sighting with a photograph, location, date and time and potential ID breathe. They are remarkable divers and a single breath may last over two hours but usually to the nearest Department of Parks and Wildlife office. Australia’s Kimberley coast has the world’s highest laevis) is reported to recorded diversity of sea snakes supporting more than lasts as little as 30 minutes when the snake is actively swimming. They also use the water have a light receptor The information you provide will help scientists and conservation managers better one third of all known species, with at least three surface for resting (especially at night), basking in the sun and drinking fresh water during on the tip of its tail. This understand these fascinating creatures and assist in their conservation. species found only in this region. Sea snakes occupy rain. Daily home ranges are poorly understood, but studied species such as the Olive and may allow sheltering varied habitats in the Kimberley, ranging from deeper Turtle-headed Sea Snakes rarely move further than 2000 m2. snakes to keep their offshore waters to shallow coral reefs and mangroves. tail paddles retracted Information current as June 2015 Some Kimberley species have extremely small and out of reach of Photo credits: Arne Rasmussen - H. macdowelli (L) | Brad Maryan - A. apraefrontalis, A. duboisii, A. foliosquama, distributions and are considered critically endangered predators.. A. mosaicus, E. annulatus, H. curtus (L), H. czeblukovi, H. elegans (L), H. kingii, H. peronii, H. platurus | Clay Bryce - A Spine-bellied Sea Snake H. stokesii feeding, Hibernia Reef | David Gower - H. elegans (R) | Jenna Crowe-Riddell - A. fuscus, H. platurus or endangered. For example, the Short-nosed Sea (Hydrophis curtus) caught as head | Kate Sanders - E. annulatus mating, H. coggeri, M. gracilis | Lochman Transparencies - H. darwiniensis on Snake (Aipysurus apraefrontalis) and Leaf-scaled Sea bycatch in a fishing trawler mudflat | Nick Hobgood - M. colubrinus | Peter Mirtschin - H. macdowelli (R), H. major (Adult) | Steven Lindfield - Snake (Aipysurus foliosquama) have disappeared cover photo of A. laevis | Vinay Udyawer - bycatch | all other photos by Ruchira Somaweera. from offshore Ashmore and Hibernia Reefs and are Conservation Status Thanks to: Paul Doughty, Erina Young, Tracy Sonneman, Kat Atkinson & Rebecca Bray. now known only from scattered records along the Sea snakes are a conspicuously understudied group of Australia’s marine vertebrates.