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Diving & SnorkellingScuba diving at the Lizard Island Research Station is conducted under occupational diving regulations. A change to Queensland law will affect many divers after 31 October 2008. Prospective divers should read the LIRS Diving Regulations in conjunction with information provided here about scientific diving in Queensland after that date. Queensland law requires occupational divers to have a current dive medical to Australian Standard 2299. While this medical can be obtained outside Australia, in practice it is difficult to verify that such medicals have actually been done to that standard. For this reason, it is preferable to have to dive medical done in Australia prior to coming out to the island. Information is provided here about dive medicals. LIRS recognises two categories of snorkeller: independent snorkellers and group snorkellers. Independent snorkellers accept responsibility for their own safety while snorkelling. Group snorkellers are supervised by suitably qualified members of their own group. There are risks associated with entering any body of water and additional risks exist in coral reef environments. All prospective visitors should make themselves aware of these issues and consider how to manage the risks. A risk assessment must be conducted by each group before they will be allowed to dive or snorkel using the Station's equipment. Frequently asked questions are answered below. Please contact the Directors with any other queries. What sort of wetsuit should I bring?Surface water temperature ranges from 30 degrees Celsius in summer to 23 degrees C in winter. It is usually windy in winter so wind chill is a consideration during trips in the Station's open boats. Scuba divers who spend a long time in the water each day (i.e. multiple dives of more than an hour each) generally wear at least a full length 5 mm suit year round, often adding a vest and hood in winter. For single scuba dives of up to an hour, a 1 mm long suit or 3 mm short suit keeps most people comfortable between October and March but additional warmth is needed outside these months. Snorkellers do not usually need a wetsuit for warmth between October and March and a 3 mm long suit or a 5 mm short suit are usually adequate during the cooler months. As well as warmth, protection from stingers (see below) and from sun should also be considered. Are deep water, strong currents, rough seas and poor visibility hazards for diving at Lizard Island?The water is less than 20 metres deep at the base of the reef all around the Lizard Island group and depth does not exceed 35 metres within a kilometre of the reef crest. Most research diving is conducted in water less than 10 metres deep. Moderately strong currents can occur at particular places and at certain times but there are many places where currents are nil to slight. Lizard Island is big enough to provide some protection from wind-generated waves on its lee side in all but the most extreme weather condtions. Underwater visibility is normally 8 to 12 metres but extreme weather conditions can reduce it substantially. Are box jellyfish a problem at Lizard Island?Box jellyfish (Chironex fleckeri) can be lethal but these animals are usually found close to the mainland. There have been no reports of box jellyfish sightings or of box jellyfish stings at Lizard Island during the past 15 years, which is as far back as local knowledge goes. The risk of encountering a box jellyfish at an offshore locality such as Lizard Island is very low but it is probably higher during and after flood conditions on the mainland during summer. A lycra suit or a wetsuit provides protection to the parts of the body that it covers. What about irukandji and other marine stingers?Irukandji syndrome is a very painful and potentially deady reaction to stings from a range of jellyfish species. The small, transparent jellyfishes that cause irukandji syndrome can be found in offshore waters. There has been an increase in the number of reported irukandji stings in Queensland in recent years, including two deaths. The first known irukandji sting at Lizard Island occurred in March 2004. A 21 year old male was stung on the forearm and had to be evacuated to Cairns by the Royal Flying Doctor Service. He had an unpleasant 48 hours but recovered completely. Other marine stingers also occur at Lizard Island. These can cause pain but are not lethal and they usually occur during the warmer months, especially during northwesterly monsoon condtions. Again, a lycra suit or a wetsuit provides protection to the parts of the body that it covers. And what about sharks and crocodiles?Many kinds of sharks are found in the waters around Lizard Island. The ones most commonly seen are white-tip reef sharks (Triaenodon obesus), black-tip reef sharks (Carcharhinus melanopterus) and grey reef sharks (Carcharhinus amblyrhynchos). There is only one shark attack known from Lizard Island within the past 20 years and it is based on an anecdotal report. It occurred in the 1980s when a person swam out to examine the floating carcase of a black marlin. The attack was not fatal but the extent of the victim's injuries is unknown as is the species of shark involved. Rarely, research divers have reported incidents of sharks approaching closely and on one occasion a researcher was bumped by a shark. Estuarine crocodiles (Crocodylus porosus) are common on the mainland adjacent to Lizard Island and they are able to swim long distances at sea. While they are extremely rare in offshore reef habitats in this area, crocodiles have been seen by reliable observers at Lizard Island on three occasions since 1996, most recently in 2003. All the crocodiles were small (1 to 2 metres long). They did not appear to stay at Lizard island for very long because each occasion involved several sightings within a short period of time, then years would pass before the next sighting. Relevant links
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