Duiker Island is a small granite islet just offshore from Hout Bay harbour, home to a large Cape fur seal colony. Boat trips run from the harbour several times a day and take about 30 minutes, circling the island at close range. At peak season the rocks are almost invisible under the seals — adults, pups, and juveniles stacked on every surface — and the noise and smell are memorable.
The trip is short but worth taking if you haven't seen fur seals in number. The harbour area where boats depart also attracts Cape cormorants, kelp gulls, and occasionally African penguins drawn in by fish discards from the fishing boats. The water between the harbour and the island is calm enough for kayaking in good weather.