As always, swimmers should be careful of dangerous ocean creatures, especially jellyfish. The park authority posts warning signs during jellyfish season. Most jellyfish in the area will cause nothing more than a painful sting, but deadly box jellyfish have also been reported on rare occasions, and there is at least one reported case of a child dying from box jellyfish stings in the park. Jellyfish stings should be rinsed with seawater then treated with vinegar, if it is available. If you are stung by a box jellyfish, seek immediate medical attention, and they are known to be fatal.
The western tip of Gaya Island, directly opposite the city of Kota Kinabalu, is populated by a floating colony of mostly illegal immigrants. This part of the island is locally considered to be a dangerous area due to a high risk of crime. Most other locations on Gaya Island, however, including the Gayana Resort, Police Beach, and the dive center, are far from this part of the island, so you shouldn't have any problems.
fees/permits
Sabah Parks diving permits are RM 50 for Non-Malaysians and RM 20 for Malaysians. Islanda conservation fee is RM 10 for adults.