Research Training Program

Elisa Maldonado
University of California, Los Angeles
Los Angeles, CA

David L. Pawson, Ph.D.
Supervising Scientist
Department of Invertebrate Zoology

"The Research Training Program was a dream come true. Never before have I been so completely surrounded by science and people who are fascinated by all that science is."

Deep-sea organisms, in general, are the least understood animals on this planet. Little is known about the feeding behaviors of deep-sea feather stars (related to starfish and sand dollars - known collectively as echinoderms). Recent advances in deep-sea technology have allowed scientists to observe these animals in their natural habitat from deep-sea submersibles. From 1983 to 1989, a survey of the echinoderms of the Bahama Islands was made using the Johnson-Sea-Link submersibles. The present study focused on the feeding behaviors and preferred habitats of twelve feather star species observed on the submersible dives. Feather stars are filter feeders that arrange their arms in a variety of ways in order to capture food. The food is then carried to the mouth in special grooves. Still photographs and videos were analyzed to determine whether each species of feather star displayed a specific feeding posture and habitat preference. Specimens from the Smithsonian collections were examined to confirm the identifications in the videos and photographs. It was determined that each species of feather star arranges its arms in a specific way to feed, and prefers certain habitats. Feather stars arrange their arms in three ways: parabolic (arms arranged like a bowl), fans, and radial filtration fans (arms arranged like spokes of a bicycle wheel). Animals that display a parabolic feeding posture typically inhabit narrow, elevated perches such as gorgonians and sea lily stalks. Those that arrange their arms in radial filtration fans are most commonly found on hard substrates such as rocks, sponges, and corals. Most of these behaviors are also exhibited by shallow-water feather stars. This project is the first detailed study of ecology of deep-sea feather stars. The ocean covers most of our planet, yet life on the bottom of the ocean is still a mystery. This project is important because it offers a piece to the deep-sea puzzle.