Prey characteristics and dietary composition in intertidal astrostole scabra (Echinodermata: Asteroidea)

Abstract

Dietary composition in juvenile Astrostole scabra at Kaikoura, New Zealand (42°25′S, 173°42′E), changed qualitatively with increased seastar size so that food was partitioned amongst starfish size classes according to a combination of prey species and size. Small A. scabra fed more frequently than large specimens. Size‐discriminant feeding was evident as large Turbo smaragdus and Risellopsis varia, small Melagraphia aethiops, and intermediate sized Micrelenchus dilatatus, Ischnochiton maorianus, Onithochiton neglectus, and Amaurochiton glaucus were consumed in proportions greater than those found in the habitat. Major prey species have both spatial and size refuges from predation. © 1981 Taylor & Francis Group, LLC.