Date of Original Version
We tested whether fishers’ local ecological knowledge (LEK) of two fish life-history parameters, size-at-maturity (SAM) at maximum body size (MS), was comparable to scientific estimates (SEK) of the same parameters, and whether LEK influenced fishers’ perceptions of sustainability. Local ecological knowledge was documented for 82 fishers from a small-scale fishery in Samaná Bay, Dominican Republic, whereas SEK was compiled from the scientific literature. Size-at-maturity estimates derived from LEK and SEK overlapped for most of the 15 commonly harvested species (10 of 15). In contrast, fishers’ maximum size estimates were usually lower than (8 species), or overlapped with (5 species) scientific estimates. Fishers’ size-based estimates of catch composition indicate greater potential for overfishing than estimates based on SEK. Fishers’ estimates of size-at-capture relative to size-at-maturity suggest routine inclusion of juveniles in the catch (9 of 15 species), and fishers’ estimates suggest that harvested fish are substantially smaller than maximum body size for most species (11 of 15 species). Scientific estimates also suggest that harvested fish are generally smaller than maximum body size (13 of 15), but suggest that the catch is dominated by adults for most species (9 of 15 species), and that juveniles are present in the catch for fewer species (6 of 15). Most Samaná fishers characterized the current state of their fishery as poor (73%) and as having changed for the worse over the past 20 years (60%). Fishers stated that concern about overfishing, catching small fish, and catching immature fish contributed to these perceptions, indicating a possible influence of catch size-composition on their perceptions. Future work should test this link more explicitly because we found no evidence that the minority of fishers with more positive perceptions of their fishery reported systematically different estimates of catch-size composition than those with the more negative majority view. Although fishers’ and scientific estimates of size-at-maturity and maximum size parameters sometimes differed, the fact that fishers make routine quantitative assessments of maturity and body size suggests potential for future collaborative monitoring efforts to generate estimates usable by scientists and meaningful to fishers.
Mclean, Elizabeth Layli and Forrester, Graham E., "Comparing estimates of size-at-maturity and maximum body size made by fishers and scientists as indicators of potential overfishing" (2017). Marine Affairs Data Sets. Paper 1.