Reacción a "Marine heatwaves cause an annual decline of almost 20% in fish biomass"

This study synthesises a huge amount of data collected during decades of research on fishery resources in the northern half of the Atlantic Ocean. The results are presented clearly and conceptually through a series of highly illustrative figures, although behind this apparent simplicity lies a remarkable effort of data collection, standardisation and analysis: more than 123,000 samples taken between 1993 and 2021.

Obtaining robust and comparable time series on a large scale is extraordinarily complex in marine ecology, so the value of this work lies not only in the magnitude of the dataset, but also in its methodological consistency over time. This provides solid support for its conclusions on how progressive warming reduces total fish biomass, while marine heatwaves have varying effects depending on the region and species in question. Furthermore, its results are consistent with trends previously described on a smaller scale and consolidate the accumulated evidence on the effects of climate change on marine ecosystems.

As with any scientific study, there are limitations that must be taken into account. In the case of predictive models, it is not always possible to incorporate other natural and anthropogenic factors that also influence biomass, such as fishing pressure or other ecosystem changes. Furthermore, the data comes from scientific trawling campaigns, which means that the conclusions mainly refer to the fish communities associated with the sampled habitats, leaving out part of the coastal communities and other environments not covered by this methodology.

Overall, this is a highly reliable study that clearly contributes to unravelling the changing trends of numerous fish stocks in the face of rising sea temperatures. Its implications for management are clear: the authorities responsible for regulating fishing effort should incorporate this type of evidence into their decision-making frameworks, promoting more flexible management models with greater capacity to respond to climatic anomalies such as marine heatwaves, the frequency and intensity of which are expected to increase in the coming decades. Persisting with static exploitation schemes in the face of such a dynamic climate system would pose a growing risk to long-term sustainability.