Sea cucumbers are the creatures you see lying perfectly still on the beds of the reefs. They are delicate and will tear instantly if pulled or yanked. Its surface is very sticky and is referred to as a "velcro layer." The cucumber has no real self-defense mechanism, except for shooting out a long sticky thread.

There are many types of sea cucumbers in Hawai'i. One type (photographed above on Coconut Island) is the red water balloon sea cucumber (Ophiodesoma spectabilis). Not found in many places in Hawai'i, it is an unofficial mascot of Kaneohe Bay. Most sea cucumbers have "tube feet," like underwater suction cups, to help them move and hold onto the bottom. Ophiodesoma does not have tube feet. If you were to move this cucumber to a place with heavier wave action, it would get pushed around in the surge. The Ophiodesoma has a very soft body and the only thing that gives it any shape is the pressure of the water inside it. It has the shape and feel of a long, limp water balloon. Again, in heavy surge, this sea cucumber would get torn apart. Therefore, it is somewhat unique to Kaneohe Bay because of its unusually calm waters.