Wind-driven ocean upwelling systems along the coast of the Eastern Tropical Pacific (ETP) enrich the warmer surface waters with nutrients from cooler depths. The complex dynamics and cycles of these highly productive environments support several key fisheries for the human communities that extend from the Gulf of California to northern Peru.
To understand how future impacts of climate change might alter both the marine biogeography of and food security within the ETP, the authors used GBIF-mediated occurrence data to create environmental niche models for 505 fishes and invertebrates commonly caught in the region’s shrimp trawl, small-scale, small pelagic and large pelagic fisheries.
The results showed similar geographic trends across each fishery, though changes in direction and depth varied more widely. Variables with the greatest impact on shifts in suitable habitats turn out to be rising temperatures and falling oxygen levels, as many species seem likely to shoal in shallower and more oxygen-rich waters, rather than departing for deeper ones.
The Central American coast and small-scale fisheries likely face the most severe local losses of species and suitable habitat, though colonization by range-shifting species from elsewhere may in part compensate in areas of high species turnover. In such a complex region, even positive outcomes like gains for shrimp fisheries may signal deprivation elsewhere, as increased pressures on bycatch species exert higher economic and social costs in a region of underreported catches, employment and incomes.