Inhabitants of open waters

The pelagic community is made up of organisms that swim or float in open waters, whether in the open sea or above the continental shelf. These are species that do not directly depend on the seabed, although they may visit it occasionally.

Many of these organisms spend virtually their entire lives in the vastness of the sea, travelling great distances in search of food.

Bodies designed for speed

Pelagic fish typically display:

• Silvery colouring, which reflects light and makes them harder to spot.
• Streamlined body shapes, ideal for swimming at speed.
• Powerful musculature, which allows them to cover great distances.
• Dark colouring on the back and pale on the belly, a camouflage strategy that helps them blend in with both the dark depths below and the sunlight above.

Protection and hunting strategies

Some species live in large shoals, a strategy that allows them to:

• Better protect themselves from predators.
• Hunt more effectively.

These species are known as gregarious.

In contrast, other species are solitary, and only occasionally interact with individuals of their own species, hunting on their own.

Life tied to the seabed

The benthic community is made up of organisms that are closely dependent on the seabed, from which they obtain shelter, food and protection.

Benthic fish typically display:

• Brown colours or dark patches, to blend in with the substrate.
• A more rounded tail, which allows them to swim without creating turbulence and remain less conspicuous.

These adaptations help them camouflage themselves and avoid being detected by predators or prey.