Movie or miniseries about people shipwrecked on an island with an abandoned military facility and Aborigines

It was about some shipwrecked survivors. They get onto an island and one man is attacked in the water by something you can’t see. Later at night he begins to mutate and goes to the sea. Then the other survivors find this abandoned military facility. They find Aborigines and they gave some bananas to the survivors, and the bananas began to swell while everyone is sleeping. I remember watching this in the ’90s.