Fraser Island is home to approximately 150 Dingoes - Australia's wild dog. These animals can become aggressive (a 9 year old boy was killed in 2001) and should not be approached or fed. Feeding of dingoes carries a $250 fine, and all food should be secured (in vehicles or food boxes) when unattended.
Swimming in the ocean is not recommended owing to both the dangerous surf conditions and the number of sharks that inhabit the waters (Indian Heads is a shark breeding ground).
Drive safely on the sand and obey the speed limits - the beach is classed as a highway, so police will run speed checks and breath tests for drivers. Speed limit on the main beach is 80km/h and on soft sand tracks 35km/h.
Due to the temperate climate, saltwater crocodiles are not normally present within Fraser Island's waterways. However, on very rare occasions individual saltwater crocodiles do (for reasons unknown, possibly territorial disputes or even global warming) swim southward and find Fraser Island's mangroves rich with prey items (Barramundi and Bull sharks are among this species favorite meals) and low on competition. This is VERY rare and almost unheard of, yet the presence of a large (4 meter) male saltwater crocodile was confirmed. This is important information for both travelers to Fraser Island (as swimming is a popular and usually safe activity) and for the survival of the crocodile (man-eaters are usually shot.)