Symbiotic relationships occur all around us every day of our lives. They are quite simply a relationship between two different species where at least one species benefits. There are three main types of symbiotic relationships, which are mutualism, commensalism, and parasitism. The main one we’ll focus on today is mutualism, which is where both organisms in the relationship benefit from each other. The Greater Cleveland Aquarium has multiple examples of this happy relationship!
Let’s start out by taking a journey into our live coral exhibit, because that happens to be the site of not one, but TWO mutualistic symbiotic relationships…and both involve you guessed it…coral! The first one involves a very famous movie star that goes by the name of Nemo. Now most people associate the clown anemonefish with anemones, hence the name. However, in this particular exhibit, the anemonefish have a relationship with a type of coral known as Ricordea florida, which doesn’t actually have a common name. This coral protects the anemonefish with its stinging tentacles, which the anemonefish are immune to because of a protective mucous coating. In return, the anemonefish gives protection to the coral by being aggressive and fighting away other fish that might otherwise prey on the coral. Also, the coral can feed on bits of food from the anemonefish’s meal. Everybody wins!
Coral play a role in our aquarium in multiple mutualistic symbiotic relationships. The next one we’ll look at is the connection between coral and zooxanthellae. Zooxanthellae, if you’ve never heard of them, are plant-like microscopic algae that live within the tissues of coral. The coral, once again, offer a protected home with their stinging tentacles. The zooxanthellae also receive the compounds necessary for photosynthesis from the coral, which is why coral need clear, low-turbulent waters to grow in, so the sunlight can reach them. Once photosynthesis is complete, the zooxanthellae transfer up to 90% of the products to the coral, which include oxygen and carbohydrates. The most fun and beneficial part for us humans is that the zooxanthellae provide the coral with the many different vibrant colors that are seen on coral reefs.
Our next relationship takes place in our stingray touch pool where there’s an interaction between our stingrays and the cleaner wrasse. While a stingray is resting on the bottom, a cleaner wrasse will use that opportunity to swim up and start the process. The cleaner wrasse, as its name suggests, cleans the stingray of dead skin and parasites, essentially getting an easy meal. So the stingrays stay clean while the wrasse stay full! In the wild, the stingrays would also be a form of protection for the wrasse but that isn’t an issue in our friendly touch pool. Be sure to look carefully for these cleaner wrasse, since not everybody notices them.
Our last symbiotic relationship covers one that pertains to us humans directly. One of our newer exhibits at the Greater Cleveland Aquarium is the invertebrate touch pool, which can be found in the coastal gallery right by our stingray touch pool and is home to many different invertebrates, including cleaner shrimp. In the wild, these shrimp would receive their food by removing external parasites and old skin from eels, groupers, and other fish. Here at the aquarium though, guests can walk up and place their fingers in the water for a free manicure! The cleaner shrimp hop right on the fingers and start cleaning away. Now hopefully we don’t have any external parasites, but old skin we surely have – so that makes a great meal for the shrimp.