Particle-size selection by Pseudopolydora paucibranchiata (Polychaeta: Spionidae) in suspension feeding and in deposit feeding: influences of ontogeny and flow speed

摘要: Pseudopolydora paucibranchiata Okuda suspension feeds and deposit at the sediment-water interface, where it is exposed to a variety of particles differing in physical characteristics nutritional value. In flume experiments (conducted August 1994 May 1995) with two sizes either suspended or deposited beads, I measured particle-size selection separately each feeding mode. The same influences palp width ambient flow speed were observed At velocities ≤0.74 cm s-1 there no relationships between proportion gut contents composed large beads. ≥1.8 worms narrower palps ingested relatively fewer beads (and more small beads) than did wider palps. Palp body length linearly related, results similar when analyzed as independent variable. As increased, selectivity changed worm-size-specific manner: