Interactive effects of flow speed and particle concentration on growth rates of an active suspension feeder
Limnol. Oceanogr., 44(4), 1999, 1120-1131 | DOI: 10.4319/lo.1922.214.171.1240
ABSTRACT: Suspension-feeding organisms dominate subtidal habitats in the Gulf of Maine (GOM) at depths of 25-40 m. Parasmittina jeffreysi is an encrusting cheilostome bryozoan found in this zone throughout the GOM. Regional variation between coastal and offshore locations in both flow speed and particle concentration makes the GOM an ideal location to study the effect of these factors on the growth of P. jeffreysi. Particle flux measurements at two offshore and two coastal sites indicated that flow speeds were >3-fold greater offshore than at coastal sites. Chlorophyll a concentrations and particulate quantity and quality were greater at offshore sites, but sedimentation rates were greater in the coastal region. The growth rate of P. jeffreysi was measured at each of the sites using unob-structed colonies free from spatial competition and colonies that remained within their natural community.