Nereus Program Director (science) William Cheung (UBC) is a co-author on a new open access study recently published in ICES Journal of Marine Science, “Bioenergetic influence on the historical development and decline of industrial fisheries.” The authors look at the historical rise and plateau/decline of industrial fisheries and catches ranging from high to low latitudes, looking at different influential factors on catch peak size, such as environmental characteristics and the global spread of fishing technology. They focused on Large Marine Ecosystems in 66 different global ocean regions, describing catch reconstructions from Sea Around Us in combination with the bioeconomic BOATS model, incorporating fishing technological progress as a primary cause of the changes in fish catches over time. They found that historically, the progression of fish catches across the world’s oceans tracks closely with and is strongly influenced by both economic development (technology) and variations in ocean water temperature, with peak catches occurring earlier in more northern latitudes before spreading further south toward the equator. You can read the full abstract below.
The global wild capture fishery expanded rapidly over the 20th century as fishing technology improved, peaking in the 1990s as most fisheries transitioned to fully- or over-exploited status. Historical records for individual large marine ecosystems (LMEs) tend to echo this same progression, but with local variations in the timing and abruptness of catch peaks. Here, we provide objective descriptions of these catch peaks, which generally progressed from high- to low-latitude LMEs, and attribute the temporal progression to a combination of economic and ecological factors. We show that the ecological factors can be remarkably strong by using a spatially resolved, observationally-constrained, coupled macroecological-economic model to which we impose an idealized, globally homogeneous increase in catchability. The globally-uniform technology creep produces a spatial progression of fishing from high-to-low latitudes that is similar to observations, primarily due to the impact of temperature on ecosystem metabolism. In colder LMEs, low respiration rates allow the build-up of larger pristine standing stocks, so that high-latitude fisheries are profitable earlier, at lower levels of fishing technology. We suggest that these bioenergetic characteristics contributed significantly to the historical progression of this human-ecological system.
The above summary was adapted from the reference below:
Guiet, J., Galbraith, E.D., Bianchi, D., & Cheung W.W.L. (2020). Bioenergetic influence on the historical development and decline of industrial fisheries. ICES Journal of Marine Science, doi:10.1093/icesjms/fsaa044. link.