title: Combined effects of water flow and copper concentration on the feeding behavior, growth rate, and accumulation of copper in tissue of the infaunal polychaete Polydora cornuta.
abstract: We performed an experiment in a laboratory flume to test the effects of water flow speed and the concentration of aqueaous copper on the feeding behavior, growth rate, and accumulation of copper in the tissues of juvenile polychaetes Polydora cornuta. The experiment included two flow speeds (6 or 15 cm/s) and two concentrations of added copper (0 or 85 μg/L). Worms grew significantly faster in the faster flow and in the lower copper concentration. In the slower flow, the total time worms spent feeding decreased significantly as copper concentration increased, but copper did not significantly affect the time worms spent feeding in the faster flow. Across all treatments, there was a significant, positive relationship between the time individuals spent feeding and their relative growth rate. Worms were observed suspension feeding significantly more often in the faster flow and deposit feeding significantly more often in the slower flow, but copper concentration did not affect the proportion of time spent in either feeding mode. The addition of 85 μg/L copper significantly increased copper accumulation in P. cornuta tissue, but the accumulation did not differ significantly due to flow speed. There was a significant interaction between copper and flow; the magnitude of the difference in copper accumulation between the 0 and 85 μg/L treatments was greater in the faster flow than in the slower flow. In slow flows that favor deposit feeding, worms grow slowly and accumulate less copper in their tissue than in faster flows that favor suspension feeding and faster growth.
authors.affiliation: Department of Biology and Coastal and Marine Institute, San Diego State University, 5500 Campanile Drive, San Diego, CA, 92182-4614, USA. mcolvin@spawar.navy.mil.
authors.forename: Marienne A
authors.initials: MA
authors.lastname: Colvin
authors.affiliation: Department of Biology and Coastal and Marine Institute, San Diego State University, 5500 Campanile Drive, San Diego, CA, 92182-4614, USA.
authors.forename: Brian T
authors.initials: BT
authors.lastname: Hentschel
authors.affiliation: Marine Biology Research Division Scripps Institution of Oceanography, University of California, 9500 Gilman Drive, La Jolla, San Diego, CA, 92093-0202, USA.
authors.forename: Dimitri D
authors.initials: DD
authors.lastname: Deheyn
mesh_terms: D000818:Animals; D003300:Copper / Q000378:metabolism / Q000633:toxicity*; D005247:Feeding Behavior / Q000187:drug effects; D011077:Polychaeta / Q000187:drug effects / Q000502:physiology*; D014874:Water Pollutants, Chemical / Q000378:metabolism / Q000633:toxicity*
chemical_list: D014874:Water Pollutants, Chemical; D003300:Copper
keywords: Benthos; Copper; Deposit feeding; Flume experiment; Polydora cornuta; Suspension feeding