Percula Clownfish - Habitat

Habitat

Anemonefish are specialized coral reef fish that live within host anemones and are found in warmer waters in the Pacific Ocean, Indian Ocean, off northwest Australia, southeast Asia and Japan. Both the A. percula and the anemones reside in shallow waters and the depth usually does not exceed twelve meters with water temperatures ranging between 25–28 degrees C. Host anemones, which are tube-like organisms that reside on coral reefs, are usually occupied by only one anemonefish species because one species will out-compete and exclude other species when they inhabit the same host anemone. Unless there was a significant size difference, two anemonefish species will show aggression towards each other when trying to occupy the same host anemone. This is why the supply of nearby anemone hosts so strongly influences A. Percula’s ability to achieve recruitment and survival in general. A primary host anemone is where an anemonefish is found at a high frequency and a secondary host anemone is where an anemonefish is found at a relatively low frequency. The distribution and availability of sea anemones is limited by the activity of photosynthesis of algae that occupy the anemones’ tentacles. Secondary hosts are usually only used if there is a severe lack of available primary hosts. When many different species of anemonefishes occupy similar habitats, they tend to spread themselves out according to smaller microhabitats and available species of anemones. The A. Percula and A. Perideraion both essentially live within the H. Magnifica anemone but the A. Percula has the highest selection ratios with the S. Gigantea. A study done by Elliot & Mariscal in the region of Madang, Papua New Guinea found that all of the H. Magnifica anemones that were censused were occupied by the A. Percula and A. Perideraion. The A. Percula generally occupies anemones that are near shore while the A. Perideraion occupies anemones that are more offshore. Anemonefish will not occupy anemones if they are in shallow water or if they are too small. This is because shallow waters give an inhabitable environment for the A. Percula because of the lower salinity levels, increased temperatures and they would be exposed during low tides. Also, small anemones would not provide protection from predators. The A. Percula and the host anemone are very important to one another and interact in a symbiotic relationship. The A. Percula cleans the host anemone by consuming algae residue and zooplankton such as copepods and larval tunicates. They also protect the anemone from polyp consuming fish and other predators, while the clown fish is protected from predators by the anemone. The A. Percula will sometimes carry pieces of food to the host anemone for later consumption. In most cases the host anemone then devours the food that the A. Percula stored around it. Chances of survival for both parties involved are increased through this co-existence.