Abstract
The purpose of this paper is to identify likely ranges of costs, market returns, and ecosystem benefits associated with three different oyster (Eastern oyster, Crassostreia virginica) production methods: extensive bottom harvest, intensive off-bottom aquaculture, and non-harvested reefs. As part of this endeavor, this paper also compiles the limited and disparate literature on costs, yields, and returns associated with commercial oyster production. I use Monte Carlo simulation to estimates the likely distribution of gross market returns, gross nonmarket benefits associated with four ecosystem services, and net benefits. I find that extensive bottom harvest has the lowest and least variable per-acre cost, whereas intensive off-bottom aquaculture and non-harvested reefs have much higher and more variable per-acre costs. Gross market returns are lower but also less variable for bottom harvest, whereas they are higher but more variable for off-bottom aquaculture. I find that gross nonmarket benefits for non-harvested reefs are relatively high with relatively little variability, whereas those of off-bottom aquaculture are relatively low with low variability. Gross nonmarket benefits for bottom harvest are estimated to be highly variable. These results are driven by the contribution of market returns, and consequently, gross benefits associated with non-harvested reefs are much lower. When market returns, nonmarket benefits, and costs are considered together, bottom harvest is net positive, with moderate upside potential. Off-bottom aquaculture has the greatest upside potential, but also substantial downside potential, with mean returns at or near zero. Because non-harvested reefs have no market benefits, and because of the relatively high cost, most of the distribution of net benefits lies in the negative range.
