The progressive growth of incrusting algae causes the formation of small cracks between the rocks, thus creating a habitat that is suitable for numerous fish and invertebrates. Generally, water erosion forms a series of tunnels and galleries, which are known as underwater caves, which give very peculiar scenery generally poor in organisms. In these places, the little light there is prevents the growth of vegetable life and as we move inside, the fauna on the walls becomes poorer and poorer until it practically disappears. The same thing happens with other parameters: the oxygen, temperature and nutrients are scarcer on the inside.

In tunnels, on the other hand, thanks to the currents that facilitate water circulation, the walls have a richer fauna, above all filtering invertebrate animals. A similar thing happens with cracks and overhangs. Here, despite not being completely enclosed, the light that reaches them is poor, and as with caves and tunnels they become the favorite habitat or hiding place for a certain number of organisms.

In this way, we can find species that use these places as a refuge, as is the case of the conger eel; others, on the other hand, use them as a favorite habitat to carry out their lives: lobsters. We can also find seasonal fish such as striped red mullet and certain gobies.

Lobster (Palinurus elephas)

Dusky grouper (Epinephelus marginatus)

Other common marine organisms that can be found in this community:

• Red scorpionfish (Scorpaena scrofa)
• Brown meagre (Sciaena umbra)
• Black scorpionfish (Scorpaena porcus)