The marine life of the Galapagos is exceptionally rich for the tropics, therefore is another fascinating world that awaits the visitor. What little we can see of life in the sea is so different from our experiences on shore and so beautiful that we cannot fail to be enchanted by it. Today, during our visit to Genovesa Island, the trail took us alongside a tidal pool, which was teeming with life. We got to see, at very close quarters, one of the inhabitants of the intertidal zone: the yellow-tailed damselfish, a native species. The damselfish are considered the farmers of the ocean, as they cultivate sea weed or algae gardens. They do this by aggressively chasing away intruders in their gardens, to avoid grazing on their algae beds. They are small fish that really illustrate the power of aggressive behavior, as they can often be seen chasing parrotfish, or others over ten times their size. Even snorkelers unwittingly putting a hand into a damselfish territory are not immune to these attacks! It was easy today to observe their territorial behavior in the pools, as they physically removed small invertebrates from the vicinity of their rocks, their faces turning pale with anger!
There are 12 species of damselfish that inhabit the Galapagos, one of whom is endemic. Colors often vary greatly within a species, depending on age, sex and reproductive stage. Damselfish are considered to be the most primitive LABROIDS because of the condition and arrangement of the some facial ligaments, lower pharyngeal jaw struts, and muscles in the throat region.