Adele Island sits a couple of kilometres off the southern coast of the park and is the most accessible target for a half-day sea kayak from Marahau. Predator-free since an extensive eradication programme in the early 2000s, it has become an important refuge for bellbird, tui, robin, and other native birds, which are now noticeably more abundant on the island than on the mainland.
Landing on the island itself is not permitted (it is a wildlife sanctuary), but the paddle around it is one of the standard kayak loops out of Marahau. The crossing can be choppy when the northwesterly comes up in the afternoon, so most guided trips set off early.