Evidence of ocean warming in Uruguay’s fisheries landings: the mean temperature of the catch approach

Abstract

Distribution, abundance and life history traits of marine fish and invertebrates are increasingly affected by ocean warming. Consequently, landings of traditional fisheries and their relative species composition could potentially be modified. The mean temperature of the catch (MTC) concept, which refers to the average inferred temperature preference of exploited species weighted by their annual catch for a given area, was applied to Uruguay's industrial fisheries. This approach allowed us to assess the evidence of ocean warming in long-term Uruguayan landings (1973−2017), which were mostly obtained from a major marine warming hotspot. Results showed a marked shift in MTC through time, with the first 10−15 yr characterized by a decreasing trend, but subsequently increasing steadily over time. Long-term effects of ocean warming have led to a shift from cool-water to warm-water species in the relative representation of local landings. A significant and consistent association between sea surface temperature and MTC increase was observed, even when accounting for other drivers. This study provides the first quantitative evidence that ocean warming has been increasingly affecting Uruguayan industrial fisheries during the past decades, and calls for an urgent need to consider environmental changes to properly manage fish stocks, particularly those shared with neighboring countries.

Climate change impacts on the atmospheric circulation, ocean, and fisheries in the southwest South Atlantic Ocean: a review

“…Likewise, Uruguayan industrial fisheries landings show a long-term increase in the relative representation of species that inhabit a warmer thermal niche, concurrent with a systematic increase in SST. M. hubbsi, a cold-water species that represents the most important fishery in Uruguay and the second most important in Argentina, has also exhibited decreasing landings during the past 25 years (Gianelli et al 2019b). A poleward shift in the trailing range edge of M. hubbsi is expected as a response to warming, deserving urgent research efforts.…”

“…Impacts of long-term ocean warming on Uruguayan industrial fisheries have been recently documented (Gianelli et al 2019b). The mean temperature of the catch (MTC) over the Uruguayan shelf, which is useful to assess global warming effects on fisheries (Cheung et al 2013), was significantly correlated with SST variability over the region (Gianelli et al 2019b). The study suggests a shift from cold-water to warm-water species in landing composition from 1973 to 2017 (Fig.…”

Subsurface Ocean Warming Hotspots and Potential Impacts on Marine Species: The Southwest South Atlantic Ocean Case Study

“…The RdlP discharge modulates the input and distribution of freshwater and nutrients, impacting the marine food web and the feeding of the most abundant pelagic fishes and several marine species over the shelf (Acha et al, 2012). Although a relatively weak surface warming has been observed in the RdlP (Oliver et al, 2018), a long-term shift from cold-water to warm-water species in industrial fisheries of Uruguay suggests the impact of climate change (Gianelli et al, 2019). Whether ocean warming affects other components of the ecosystem is unknown.…”

Interannual Variability and Trends of Sea Surface Temperature Around Southern South America

“…The phytoplankton productivity sustains a diverse community of species including significant fisheries and top predators that feed on and breed in its seas (e.g., Acha et al, 2004). SST variability in this region could lead to changes in the vertical stratification and therefore affect the timing and persistence of these blooms (Pecl et al, 2014;Gianelli et al, 2019).…”