When: In the summer time if you actually want to swim in the ocean. If you just want to have a look at the penguins then anytime. Beach opens between 07:00 and 08:00 in the morning and closes between 17:00-19:30 (Long opening times in summer (Dec-March) short ones in winter)
Do: Stay away from the Penguins. Well you can get pretty close, but they are definitely not loving cuddling animals and they will let you know. If you go towards a penguin and it starts to look at you and bend its head from side to side… It’s a definite sign to back off. Especially if they have a nest close by they won’t like it. Walk around keep a respectful distance to the animals and they won’t care about you. Or lie down in the sun and watch them.
My tip: If you have a wetsuit use it. The water is freezing cold and you won’t be able to have a long swim without (unless you are very brave). So if you want to do some snorkelling and watch the penguins under water wear it to protect you from the cold.