Clownfish are one of the most recognisable fish on the Great Barrier Reef. In the 1990's, the fish was studied at schools around Australia as a perfect example of the symbiotic mutualism relationship these fish have with the living anemone, providing protection from larger fish that would eat the small clownfish, as the fish protects its home and eats potential parasites.
Anenomies have powerful stingers that will paralyse other fish who would enter the clownfishes home. As they have adapted a special mucous layer, that protects the fish from the venomous tentacles. Scientist that studied the mucous found that it mostly derived from sugars, instead of proteins. An interesting breakthrough for the species. Aquariums bost 3 main species of the fish on the reef; but in reality, there are over 27 identified anemone fish that have been studied. They usually can be identified from yellow, red, red-brown, and black colourations in different but similar arrangments. The most obvious identifying tool is looking for a fish that is living in a sea anemone.
Recently the film: Finding Nemo, has since renamed named the fish in more childish slang terms "Nemo fish". As the main character takes the form of a clownfish with a deformed pelvic fin. That gets captured and put in an Aquarium in Sydney, later conspiring to escape and return to the reef with his fellow tankmates. Ironically now the subspecies featured in the film is now at risk of becoming endangered because people more than ever want them in their tank. Despite this being almost exactly the opposite of the message of the film.
In 2014, I took place in helping develop a captive breeding program. Helping identify successful methods so that fish in the reef were left alone. During this time I observed the intelligence of the clownfish that may have originated its more common name. As the fish was quite intelligent and clever, though ultimately resulting in humour. On one occasion the fish swam up the tank cleaning hose into the waste water bucket, and successfully escaped its tank though caught in the act. Surprising both myself and the marine aquaculture students at the time.