Where can I be found?
All the coasts rich in carbonate rocks are well known for their cave landscapes - the Croatian coast of the Adriatic Sea is the best example.
Why am I important?
Underwater caves are usually connected to the surrounding seawater by small passages and openings that exchange larvae, nutrients, and sediment.
Since little or no sunlight enters a sea cave, there are very few algae.
The animals that live in these large cavities feed on particles brought in from the outside.
So you could probably describe sea caves as parasites: They consume much more energy than they contribute to the ocean ecosystem.
Who am I giving home to?
The rocks inside the caves are populated by sessile animals that feed on plankton washed up from the outside.
Corals and anemones that have found a place at the entrance of the cave have a chance to eat larger particles of plankton as well as shrimp and juvenile fish that pass by.
Farther back, in the quiet, inner areas of the caves, moss animals and sponges line up and create their own water current - so they can swirl up plankton and don't have to end up empty-handed.
In hidden, dark places, odd species such as sea squirts, which spend their lives in the dark, can be spotted occasionally.
Many free-swimming sea creatures use underwater caves to hide from predators or to rest and sleep.
Squid and octopus are the rulers of underwater caves.
Octopuses in particular use the many hiding places to hatch their eggs, but not without danger: sea eels and moray eels, the octopuses' worst enemies, are all too happy to lurk in caves.
For the avid divers among you: On your next cave dive, look up: the inner walls are lined with shrimp, lobsters, and crabs, which are much harder to spot outside.
What do I consist of?
I am a rocky cavity. Sometimes rock is all I am, sometimes you'll find sand or mud or gravel in me.
Text: Carolina Leiter
