Marine Science Faculty Publications

Evidence of Fishery Depletions and Shifting Cognitive Baselines in Eastern Indonesia

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Shifting baselines, Fuzzy logic, Local ecological knowledge, Fishery depletion, Indonesia, Raja Ampat

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We analyzed fisher interview data collected in the Raja Ampat archipelago of Eastern Indonesia to demonstrate a perceived decline in the abundance of living marine resources targeted by commercial and artisanal fisheries. The decline appeared ubiquitous among all tested species and a clear trend emerged in which older fishers recall greater past abundance than younger fishers. This provides evidence for the shifting baseline syndrome, a dangerous cognitive condition in which each generation of fishery stakeholders accepts a lower standard of resource abundance as normal. We used a fuzzy expert system to standardize and quantify the anecdotal evidence, and combine it with additional depletion indicators to produce a decadal time series of resource abundance from 1970 to present. Using governmental catch-per-unit-effort data from more recent years we hindcasted to establish an absolute scale with which to interpret the perceived decline. The interview information suggested that some exploited species may have declined by as much as an order of magnitude since 1970.

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Citation / Publisher Attribution

Biological Conservation, v. 141, issue 3, p. 848-859