학술논문

Dynamics and Feeding Activity of High-Density Aggregations of Oreaster reticulatus (Echinodermata: Asteroidea) in a Sand Patch Habitat
Document Type
research-article
Source
Marine Ecology Progress Series, 1980 May . 2(4), 321-327.
Subject
Sediments
Aggregation
Horseshoes
Chlorophylls
Density
Mann Whitney Wilcoxon U test
Marine ecology
Coral reefs
Synecology
Population size
Language
English
ISSN
01718630
16161599
Abstract
Aggregations of Oreaster reticulatus (L.) in a large sand patch amid an offshore seagrass bed (Syringodium filiforme) off St. Croix (US Virgin Islands) were characterized by protracted fronts of high density (2–7 individuals m⁻²). Fronts migrated across the sand patch at approximately 7 m d⁻¹ and were refracted and deflected at the grassbed border. Intensive microphagous feeding effected a 2-fold turnover of surface sediments in the area covered by a front during 24 h, resulting in a marked decrease in chlorophyll concentration. Conspicuously mounded feeding sites were uniformly dispersed in the wake of the fronts. Overlap among feeding sites was high indicating intraspecific competition for food.