Recent efforts to conserve fisheries stocks have included such demand-side measures as consumer boycotts to reduce demand for specific species, and the promotion of aquaculture to reduce pressure on natural stocks. This article argues that these sorts of measures can be counter-productive. The economics of the commercial fishing industry are such that decreasing demand for particular species can often have the perverse effect of increasing industry effort to catch them. This means that consumer boycotts or efforts to promote aquaculture can have the effect of accelerating, rather than ameliorating, the depletion of overfished stocks. This proposition is tested on a panel data set, covering several species over a period of almost two decades, drawn from the New England fishery. We conclude that effective conservation of depleted fisheries requires supply-side regulation such as quotas.