June 12, 2025
The paradise of sponges
Surprisingly, the first site we surveyed today had good coralligenous outcrops, although not very tall. The area was described as a rhodoliths bed and, although there are rhodoliths, coralligenous concretions are more abundant.
This coralligenous is a bit different and has more red algae and hydrozoans living on it than what we have seen so far. Red mullets are also common in the area.
The second dive was also a surprise. The bionomic map of the area said that it was just a sandy bottom. We found the densest rhodoliths bed in this area. Many sea squirts, hermit crabs, small fish, red algae, and cuttlefish.
The final ROV dive in Tramontana is close to Soller harbor. We expected a big coralligenous bed and… yes, finally it coincides with the map. It was not difficult, it is in a shallower site, around 35m, and it is the typical coralligenous with many bryozoans and sponges, but with many seaweeds covering large parts of the reef.
Most bionomic maps are wrong because they are made only with sonar. It is necessary to verify the seabed with a drop camera or much better, an ROV.
The Balearic Islands are the paradise of sponges. They are everywhere and all kinds of species. It is going to be difficult to identify all the species we have recorded.


