Sponges
Many dorid nudibranchs feed on sponges. This is why they are often found sitting directly on or beside sponge growth.
Nudibranchs are carnivores and many are highly specialised feeders. Understanding their food sources is one of the most useful shortcuts for finding and identifying them underwater.
Reference Diagram
Food source overview.
This infographic brings together the six main food-source themes on this page: sponges, hydroids, soft corals, tunicates and bryozoans, anemones, and other nudibranchs.
Sponges
Hydroids
Soft corals
Tunicates & bryozoans
Anemones
Other nudibranchs
Hydroids
Aeolids commonly feed on hydroids and may store stinging cells from their prey in their cerata for defence.
Soft corals
Some species specialise on soft corals or related animals, often matching their colour and texture.
Tunicates and bryozoans
These colonial animals are important food sources for some smaller or more cryptic nudibranchs.
Anemones
Some aeolids feed on anemones and related cnidarians, recycling their prey's defences.
Other nudibranchs
A few nudibranchs eat other nudibranchs or their eggs. Behaviour can be a valuable clue.
Why food matters for identification
A beautiful photo of a nudibranch is useful. A photo showing the nudibranch and its food source is often much more useful. If two species look similar, the prey or surrounding habitat may help separate them.
Food source
Habitat
Behaviour
Identification clue
Field tip
After photographing the animal, take a wider reference shot showing the surface it is on. Sponge, hydroid, tunicate, algae or soft coral context can be extremely helpful when identifying the species later.
Back to Nudibranchs
Return to the Nudibranchs Academy section to explore anatomy, behaviour, identification, life cycles, food sources and hotspots.
Return to Nudibranchs