During the winter the island is carpeted by succulent vegetation.
Dassen Island's waters have historically been packed with fish. Lots of fishing boats launch at Yzerfontein daily to fish for snoek off the island - the commercial fishing presents competition to the penguins. Dassen Island's waters are also filled with crayfish, but they are not for catching.
a large Angulate Tortoise (Chersina angulata) population (there is some debate about whether it is indigenous)
Gronovis Dwarf Burrowing Skink (Scelotes gronovi)
Marbled Leaf-toed Gecko (Phyllodactus porphyreus)
Dassen Island is renowned for being home to a breeding colony of African penquins (Spheniscus demersus, the only penguin species that breeds in Africa).