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Impacts of Aquatic Invasive Species on Sport Fish and Recreational Fishing in the Great Lakes: Possible Future Scenarios

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Impacts of Aquatic Invasive Species on Sport Fish and Recreational Fishing in the Great Lakes: Possible Future Scenarios Impacts of Aquatic Invasive Species on Sport Fish and Recreational Fishing in the Great Lakes: Possible Future Scenarios March 2016 HDRU Series No 16-1 Prepared by: Richard C. Ready, T. Bruce Lauber, Gregory L. Poe, Lars G. Rudstam, Richard C. Stedman, and Nancy A. Connelly Human Dimensions Research Unit, Department of Natural Resources, Cornell University HUMAN DIMENSIONS RESEARCH UNIT PUBLICATION SERIES This publication is one of a series of reports resulting from investigations dealing with public issues in environmental and natural resources management. The Human Dimensions Research Unit (HDRU) in the Department of Natural Resources at Cornell University studies the social and economic aspects of natural resources and the environment and the application of social and economic insights in management planning and policy. A list of HDRU publications may be obtained by writing to the Human Dimensions Research Unit, Department of Natural Resources, Fernow Hall, Cornell University, Ithaca, NY 14853, or by accessing our World Wide Web site at: http://www.dnr.cornell.edu/hdru. TO CITE THIS REPORT Ready, R.C., T.B. Lauber, G.L. Poe, L.G. Rudstam, R.C. Stedman, and N.A. Connelly. 2016. Impacts of aquatic invasive species on sport fish and recreational fishing in the Great Lakes: Possible future scenarios. HDRU Publ. No. 16-1. Dept. of Nat. Resour., Coll. Agric. and Life Sci., Cornell Univ., Ithaca, N.Y. XX pp. This report is available electronically at http://www2.dnr.cornell.edu/hdru/pubs/HDRUReport16- 1.pdf. TABLE OF CONTENTS Table of Contents ............................................................................................................................. i Executive Summary ....................................................................................................................... iii Acknowledgments......................................................................................................................... vii Introduction ..................................................................................................................................... 1 Methods ....................................................................................................................................... 3 Scenario Development ............................................................................................................. 3 Economic Model...................................................................................................................... 6 Scenario Evaluation ................................................................................................................. 6 Future Effects of Aquatic Invasive Species on Sport Fish ............................................................. 8 Bighead and Silver Carp ............................................................................................................. 8 Scenario AC-1 ......................................................................................................................... 9 Scenario AC-2 ....................................................................................................................... 10 Northern Snakehead .................................................................................................................. 11 Grass Carp ................................................................................................................................. 13 Hydrilla...................................................................................................................................... 14 Quagga Mussel .......................................................................................................................... 16 Economic Model ........................................................................................................................... 17 Future Effects of Aquatic Invasive Species on Sport Fishing ...................................................... 41 Asian Carp ................................................................................................................................. 41 Scenarios AC-1a and AC-2a.................................................................................................. 41 Scenario AC-1b ..................................................................................................................... 46 Scenario AC-1c...................................................................................................................... 49 Scenario AC-2b ..................................................................................................................... 52 Scenario AC-2c...................................................................................................................... 55 Asian Carp Summary............................................................................................................. 58 Northern Snakehead .................................................................................................................. 59 Scenario NS-2 ........................................................................................................................ 59 Grass Carp ................................................................................................................................. 63 Scenarios GC-1 ...................................................................................................................... 63 Scenarios GC-2 ...................................................................................................................... 67 Scenarios GC-3 ...................................................................................................................... 70 Grass Carp Summary ............................................................................................................. 73 Hydrilla...................................................................................................................................... 74 i Scenarios H-2 ........................................................................................................................ 74 Scenarios H-3 ........................................................................................................................ 78 Hydrilla Summary ................................................................................................................. 81 Quagga Mussel .......................................................................................................................... 82 Conclusions ............................................................................................................................... 86 Literature Cited ......................................................................................................................... 89 ii EXECUTIVE SUMMARY The rate of invasions of non-native aquatic invasive species (AIS) has accelerated in the Great Lakes in recent years. To date, several hundred non-native species have entered the lakes. Some AIS have been shown or are predicted to cause considerable harm, and the effects of AIS on recreational fisheries has been a point of particular concern. Recreational angling in the Great Lakes is popular and highly valued. Poe et al. (2012) estimated that Great Lakes anglers enjoy 18 million fishing days per year with a net economic value of $0.4 to 1.3 billion annually. Management decisions aimed at limiting AIS introduction or spread should be informed by estimates of the potential consequences of those AIS on this highly valued recreational fishery. Ready et al. (2012) developed a model to address this need. Based on a survey of over 3,500 recreational anglers in 12 states in the Great Lakes, Upper Mississippi and Ohio River basins, they developed a model of recreational angler behavior that explains: (a) how often anglers go fishing, (b) where they go fishing, and (c) what types of fish (coldwater or warmwater) they target. Using these data, the model estimates the net economic value that anglers receive from the sportfishing resource. The model can therefore be used to project the impact of AIS-induced changes in sportfish catch rates on recreational fishing effort and on the net economic value that anglers place on the fishery. The model estimated by Ready et al. is the most comprehensive model available for evaluating and predicting recreational angling in the Great Lakes region. However, the model has some limitations. First, the model was estimated using data on trips from a very large study region that extends far beyond the boundaries of the Great Lakes basin. A model estimated using data on angler behavior from only the Great Lakes region would better reflect angler behavior in that region. Second, the model is relatively simplistic in how it models angler behavior, particularly with regards to how anglers choose what type of fishing to do, and how that choice would change in response to changes in fishing quality. A refined model is needed that better captures how anglers make these choices. Projecting of the impacts of AIS on recreational angling and anglers requires first estimating the ecological effects of AIS on recreational fish populations.Anticipating the impacts of AIS on recreational fish populations in a large, complex system, such as the Great Lakes, is challenging. Even under the best of circumstances, there is often considerable uncertainty about the likely impacts of AIS. Trying to reach single-estimate
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