Copepods: Copepoda - Habitat

Free-living copepods live in nearly all bodies of water on the planet, including temporary pools and rain puddles. Depending on the species, they are active in open water or live on or in sandy or muddy bottoms. They are often found among plants growing along the seashore. Many species swim near the surface of the ocean, while others are found to depths of 32,814 feet (10,000 meters). A few species are found only in undersea caves, deep-sea coldwater springs, or underwater geysers called hydrothermal vents. Others live in wet sand, mud, or mosses. They are also are found in hot springs and other bodies of freshwater underground and in caves. Some copepods live in extremely salty lakes on land. They have even been found in freshwater lakes on the slopes of the Himalayas at an elevation of 18,175 feet (5,540 meters). About half of all known copepods, many of which are parasites, live on or inside the bodies of sponges, worms, echinoderms, snails, tunicates, fishes, and marine mammals.