Food sources of sublittoral, bathyal and abyssal asteroids in the northeast Pacific Ocean

Abstract

Abstract Sea stars from the sublittoral to the abyssal zone at 4260 meters depth in the northeast Pacific Ocean were examined for food source. A total of 491 specimens of 29 species were dissected for stomach content analyses. Seven species are predators; six, deposit-detritus feeders; thirteen, omnivores; and the feeding habits of three remain unknown. There are changes in feeding type with increasing depth; the relative abundance of predators decreases from 67 to 0%, and the deposit-detritus feeders, from 33 to 14%. The omnivores increase from 0% on the inner continental shelf at a depth of 50 meters to 71% on the abyssal plains. It is concluded that in the near-shore abyssal environment the deep-sea asteroids are generally facultative feeders and obtain food from the sediments as well as prey or animal remains, while in the food-rich shallow waters of the inner continental shelf the asteroid fauna are generally specialized carnivores.