There will be photographers taking pictures of those who partake in the dolphin interaction. They get right in the water and capture some great moments of you and the other members of your party, both individually and as a group.
There are sometimes photographers in other locations (such as the aviary) but they are not plentiful. We didn't see a single one on our May visit outside of the dolphin swim areas.
I would definitely have your own camera. There will be LOTS of things you want to take photos of besides the dolphin swim.....the park is spectacularly beautiful!