Biology/Natural History: P. chitonoides is essentially sedentary. The cucumber uses its ten equal tentacles to filter detritus from the water. Sticky pads on each tentacle capture the food particles. The tentacles contain toxic compounds called saponins to discourage fish from nibbling at them. Predators that ignore these chemicals or are not affected by them include Stimpson's Sun Star, the Northern Sun Star, the Leather Star, the Sunflower Star, and the Red Rock Crab. The animals spawn in the spring and a large female may release up to 34,700 eggs. The eggs form a lecithotrophic larvae followed by a pentacula larvae.