Evolution of global marine fishing fleets and the response of fished resources

Abstract

Previous reconstructions of marine fishing fleets have aggregated data without regard to the artisanal and industrial sectors. Engine power has often been estimated from subsets of the developed world, leading to inflated results. We disaggregated data into three sectors, artisanal (unpowered/powered) and industrial, and reconstructed the evolution of the fleet and its fishing effort. We found that the global fishing fleet doubled between 1950 and 2015—from 1.7 to 3.7 million vessels. This has been driven by substantial expansion of the motorized fleet, particularly, of the powered-artisanal fleet. By 2015, 68% of the global fishing fleet was motorized. Although the global fleet is dominated by small powered vessels under 50 kW, they contribute only 27% of the global engine power, which has increased from 25 to 145 GW (combined powered-artisanal and industrial fleets). Alongside an expansion of the fleets, the effective catch per unit of effort (CPUE) has consistently decreased since 1950, showing the increasing pressure of fisheries on ocean resources. The effective CPUE of most countries in 2015 was a fifth of its 1950s value, which was compared with a global decline in abundance. There are signs, however, of stabilization and more effective management in recent years, with a reduction in fleet sizes in developed countries. Based on historical patterns and allowing for the slowing rate of expansion, 1 million more motorized vessels could join the global fleet by midcentury as developing countries continue to transition away from subsistence fisheries, challenging sustainable use of fisheries' resources.

Effective fisheries management instrumental in improving fish stock status

“…2). Global catch as reported by the FAO also declined during that period, but less so than for the assessed stocks reported here, likely because fishing effort in the parts of the world without assessment has not declined (18).…”

Citizen science and marine conservation: a global review

“…Climate change [1], overfishing [2], marine pollution [3] and an increasing list of other anthropogenic drivers threaten our global oceans. Many iconic marine environments, including the Great Barrier Reef in Australia and the continent of Antarctica, are nearing or have reached their critical tipping points [4] and rising ocean temperatures and sea levels are expected to further threaten marine environments and species around the globe [5].…”

The risk of underestimating long-term fisheries creep

“…Importantly, this result concurs with Palomares and Pauly, as well as Steneck and Pauly (2019), that the creeping increase in fishing power is a primary cause for global overfishing and biomass depletion. Because this type of broadly defined, fleet-average C is used to estimate long-term changes in catch efficiency (catch-per-unit-effort), which is used to assess fish abundance and overfishing (see, e.g., Watson et al 2013 andRousseau et al 2019), finding an accurate C that fits the context is critical. Underestimating the long-term value of C would lead to an underestimate of fisheries impacts, and undervalue both the importance of incorporating creep into Ecology and Society 25(1): 18 https://www.ecologyandsociety.org/vol25/iss1/art18/ fisheries management and the feasible future impacts of further technological progress.…”