Preliminary Tests of Responses of New Zealand Mudsnails Potamopyrgus antipodarum to Copper‐Based Substrates

Abstract

AbstractNew Zealand mudsnails (NZMSs) Potamopyrgus antipodarum can enter aquaculture facilities by crawling upstream through effluent discharges. Controlling or preventing this movement would aid the growing number of facilities that discharge into waters containing NZMSs. We quantified the distance traveled and residence time of NZMSs on four copper‐based substrates and evaluated their potential for use as barriers or deterrents. Polyvinyl chloride test surfaces were left untreated (control) or were coated with copper sheet, copper mesh, an ablative marine antifouling paint containing cuprous thiocyanate, or a nonablative marine antifouling paint containing cuprous oxide. The mean distance traveled on treated surfaces was 6–16% of the distance traveled on control surfaces. When an untreated refuge area was available to NZMSs, the most effective substrate for reducing NZMS movements was copper sheet. When NZMSs had no access to a refuge area, however, the substrate treated with ablative marine antifouling paint was more effective. Copper‐based substrates could potentially be used to deter the upstream movement of NZMSs.