Cost‐effective mitigation strategies to reduce bycatch threats to cetaceans identified using return‐on‐investment analysis

Authors: 

Tulloch, V., Grech, A., Jonsen, I., Pirotta, V., and R. Harcourt

Year: 

2020

Journal/Publisher Name: 

Conservation Biology

Publisher Address: 

Volume (Issue #): 

34(1)

Page #s: 

168-179

Contact information: 

Vivitskaia Tulloch Australian Rivers Institute, Griffith University, Nathan, Queensland 4111, Australia v.tulloch@griffith.edu.au
Summary: 

Solutions to mitigate cetacean bycatch have targeted specific fisheries and gears, however, these targeted mechanisms can be effective if interactions occur only between a particular population and gear type or fishery. Most dolphin and whale populations face incidental capture from multiple fisheries and gears. Accordingly, broad-scale spatial approaches to mitigation are needed to address bycatch across multiple species at the scale at which the species occur. This study applied decision-theoretic bio-economic techniques to inform the reduction of cetacean bycatch in a case study of Australian fisheries. Spatial mapping highlighted substantial variation in the location of optimal cost-effective management strategies. Although trawl-net modifications were the cheapest strategy overall, there were many locations where spatial closures were the  most cost-effective solution (despite their high costs to fisheries) due to their effectiveness in reducing all fisheries interactions.