Management strategies to minimize the dredging impacts of coastal development on fish and fisheries

Authors

Amelia S. Wenger, University of Queensland
Christopher A. Rawson, Curtin University of Technology
Shaun K. Wilson, University of Western Australia
Stephen J. Newman, Department of Primary Industries and Regional Development, Western AustraliaFollow
Michael J. Travers, Department of Primary Industries and Regional Development, Western AustraliaFollow
Scott Atkinson, University of Queensland
Nicola Browne, Curtin University of Technology
Douglas Clarke, HDR
Martial Depczynski, University of Western Australia
Paul L A Erftemeijer, University of Western Australia
Richard D. Evans, Department of Biodiversity, Conservation and Attractions
Jean-Paul A. Hobbs, Curtin University of Technology
Jennifer L. McIlwain, University of Western Australia
Dianne McLean, The University of Western Australia
Benjamin J. Saunders, Curtin University of Technology
Euan S. Harvey, The University of Western Australia

Document Type

Article

Publication Date

6-8-2018

Journal Title

Conservation Letters

ISSN

1755-263X

Keywords

coastal development, coastal fish, dredging, fisheries, integrated coastal zone management, marine conservation, ports, seasonal restrictions, suspended sediment, threshold reference values

Disciplines

Aquaculture and Fisheries | Marine Biology

Abstract

Accelerating coastal development and shipping activities dictate that dredging operations will intensify, increasing potential impacts to fishes. Coastal fishes have high economic, ecological, and conservation significance and there is a need for evidence-based, quantitative guidelines on how to mitigate the impacts of dredging activities. We assess the potential risk from dredging to coastal fish and fisheries on a global scale. We then develop quantitative guidelines for two management strategies: threshold reference values and seasonal restrictions. Globally, threatened species and nearshore fisheries occur within close proximity to ports. We find that maintaining suspended sediment concentrations below 44 mg/L (15–121 bootstrapped CI) and for less than 24 hours would protect 95% of fishes from dredging-induced mortality. Implementation of seasonal restrictions during peak periods of reproduction and recruitment could further protect species from dredging impacts. This study details the first evidence-based defensible approach to minimize impacts to coastal fishes from dredging activities.

Recommended Citation

Wenger AS, Rawson CA,Wilson S, et al. Management strategies to minimizethe dredging impacts of coastal development on fishand fisheries. Conservation Letters. 2018;11:e12572.https://doi.org/10.1111/conl.12572