SunSafe - Skin Cancer is a serious health issue in Australia, and sunburn and sunstroke are related problems. Make sure you wear SPF 15+ sunscreen, a wide-brimmed hat and t-shirt or long sleeved shirt whenever you can in summer even on cloudy days. Particularly protect children's skin between 10AM to 2PM, as the summer sun can cause a severe burn that will at best ruin your holiday, and at worst end in a trip to the local hospital. Many media outlets list the UV Index sun factor with the weather broadcast. In summer in Queensland expect that the UV Index will be extreme every day.
Drink water - If you did a quick street survey you would quickly find out that most locals carry a bottle of water with them at most times in the summer. The humidity can take you unaware, and dehydrate you quickly. Make sure children take regular drinks if they are playing outdoors, and carry water with you on car journeys, hikes or any time you may inadvertently end up somewhere you didn't plan to be.
Saltwater Crocodiles
are common throughout the tropical northernhalf of Queensland all the way down to Rockhampton. Some people play down the threat to humans posed by the Saltwater Crocodile. The facts are that the Saltwater Crocodile has been protected for decades now and there is a healthy population in northern Australia. It is always best to play it safe as a saltwater crocodile can grow to over 5m in length, and are found both in salt and fresh water. Beaches, rivers, creeks and waterholes can be home to large crocodiles. They are not known to frequent the Great Barrier Reef but live in coastal areas and rivers in tropical Australia. Generally authoritative local advice can direct you to a place to swim which is known to be free of crocodiles or has been cleared of them.
When swimming at surf beaches, swim on beaches patrolled by Surf Life Savers and between the red and yellow flags. Surf conditions can change quickly and powerful unseen rips can cause problems for even the strongest swimmers. The flags denote the safest area to swim in and the area is monitored.
If you see signs warning swimmers that "stingers" are in the water read them carefully as some are deadly. Find a pool or use one of the net protected beach enclosures common on many main beaches.