Aquatic isopods are animals without backbones called invertebrates, and they are part of the crustacean family. These animals can be found on both land and in water. Half of all isopod species known to man live in the ocean, although some species live in fresh water.
Isopods come in different sizes, ranging from mere micrometers to a half meter in length. They all have many legs, but aquatic isopods have gills for breathing underwater. One physical characteristic all isopods share is light sensitive eyes. Aquatic isopods that live in shallow water areas tend to be nocturnal due to this characteristic, while those that live in the deep parts of the ocean where light is scarce have the advantage, able to live and swim freely whenever they choose.
These animals are primarily scavengers, consuming what drifts down the water column and settles on rocks or the substrate of the water body in which they live. There are many different forms of isopods. The majority are flat creatures; however, there are several types which have developed cylindrical bodies in order to live in ocean plants like sponges. These types of aquatic isopods feed solely by filtering food out of the water column, rather than scraping it off of rocks or the substrate like their scavenging brethren.
Aquatic isopods dwell within a large range of water bodies, including the bottoms of ponds and streams, in shallow ocean areas, and in the deep abysses of the ocean. They can also live where there is very little oxygen in the water, giving them an advantage where other aquatic creatures would perish.
Larger aquatic isopods are found in the deepest waters of the ocean. These animals are also scavengers, feasting on dead fish and crustaceans that have drifted all the way down to the ocean floor. Aquatic isopods of all sizes and shapes are important members of the oceanic ecosystem, helping to keep the cycle of life going even in the very deep sea. Check out this creepy clip of giant aquatic isopods at work.
