Economic effects of predation by scaup on baitfish and sportfish farms

Abstract

AbstractFish‐eating birds have been found to consume baitfish and sportfish raised on farms in the United States. Understanding the on‐farm economic effects of such wildlife conflicts is essential for wildlife management agencies to make informed decisions. Lesser scaup, while not widely considered a fish‐eating bird, will consume farmed fish. Baitfish and sportfish farms in Arkansas (the major baitfish and sportfish producing‐state in the U.S.) were surveyed to gather data on the cost of protecting farm crops from scaup. The values of lost sales revenue from the various species of baitfish and sportfish consumed by scaup were estimated based on a concomitant field study on the abundance, distribution, and dietary habits of scaup that visited Arkansas baitfish and sportfish farms during winters of 2016–2017 and 2017–2018. Economic effects were estimated for golden shiner, fathead minnow, sportfish, and goldfish farms. Total annual costs to scare birds from baitfish and sportfish farms were $622 ± 742 per ha. The greatest components of bird‐scaring costs were manpower (56%), truck usage (32%), levee upkeep for vehicle access to scare birds (9%), firearms and ammunition (2%), and pyrotechnic devices (1%). The combined annual economic losses, calculated as reduced revenue from fish losses to scaup plus expenditures to scare birds, averaged $683/ha for golden shiners, $695/ha for fathead minnows, $663/ha for sportfish, and $673/ha for goldfish across the two study years. The fish losses to scaup alone averaged $1.06 million per year ($0.09 million in Year 1 and $2.03 million in Year 2) for the Arkansas baitfish industry. Total direct negative economic effects on the Arkansas baitfish industry were estimated to be, on average, $5.5 million per year ($4.6 in Year 1 and $6.3 million in Year 2).