Off North Stradbroke Island it seems there are 2 must-dive sites depending on the season. In the Summer the preferred site is "Manta Bommie", to dive with the manta rays. In the Winter, the place to go is Flat Rock ("Shark Alley"), where you can dive with a group of grey nurse sharks (sand tiger sharks in the US). I was there in the winter so Flat Rock is where the boat took me for the first dive of the day. "Shark Alley" is a sandy channel about 70-80' deep between the steep rock reefs. This is where the sharks hang out. Visibility was around 50' and there was a slight current. Other than about a dozen sharks, I also saw a few turtles, eagle rays, a wobbegong shark, some other kind of stingray and lots of clownfish/anemones. The following images were stills taken from the video I took:
