Piscina natural do Atalaia (Praia do Atalaia)

The Atalaia natural pool, in the Mar de Fora of Fernando de Noronha, only forms at low tide. The surrounding landscape shows materials from the island's first and second volcanic cycles, such as Ilha do Frade, known as the guardian of Atalaia.

The pool is a nursery for octopuses, sharks, moray eels and several species of ornamental fish. Lobsters also live there, and with luck a small baby shark shows up. The great variety and number of fish make the place a good setting for macro and close-up photos. Fish, corals and sponges are well preserved, and the bottom combines biogenic sand, a carpet of algae known as turf and colonies of star coral (Siderastrea).

The pool undergoes natural silting, in which the build-up of sediment raises the bottom. When sand covers the algae and corals, the ecosystem becomes fragile and trampling causes damage, which is why it has been closed more than once. In the Mar de Fora, which includes the Leão, Sueste and Atalaia beaches, the sea tends to be calm from November to March, a time when the Mar de Dentro tends to be rough. On the island, the rainy season tends to run from March to July, and during this period the trails tend to get muddy and take longer on the way to the pool.