The Impact of El Niño on Fishery Resources and Fishing Activities
Jul 27, 2026
Leave a message
El Niño exerts profound and complex effects on global fishery resources and fishing activities by drastically altering the marine environment. Rather than simply causing a decline in overall catch, it drives a major spatial reshuffling of marine ecosystems and fishing grounds, presenting both severe challenges and new opportunities for certain regions.
Core Impact: Chain Reactions Triggered by Rising Water Temperatures
The defining characteristic of El Niño is the anomalous warming of surface waters in the eastern Pacific Ocean. This triggers a series of chain reactions:
- Contraction of habitats for cold-water species: Take the Peruvian anchoveta as an example; during El Niño years, the habitat and food sources for this cold-water species shrink significantly, leading to a sharp decline in population biomass. During the strong El Niño event of 2023–2024, the industrial catch of Peruvian anchoveta dropped by 50% compared to the previous year. This directly resulted in the quota for the first anchoveta fishing season of 2026 in Peru's north-central zone being reduced to 1.91 million tonnes-a 36.2% decrease from 2025 and the lowest level in nearly a decade.
- Poleward migration of species distribution: In search of suitable habitats, many fish species migrate toward higher latitudes (colder waters).
In Chinese waters, a study published in *Nature Climate Change* found that salinity changes driven by El Niño are causing the habitats of 31 commercially important fish species to shift southward, with some shifting by as much as 2.5 degrees of latitude.
In the Northwest Pacific, El Niño and La Niña events cause fluctuations in the marine environment (such as temperature and ocean currents), affecting the transport, distribution, and recruitment of chub mackerel larvae and juveniles, thereby causing interannual fluctuations in stock recruitment.
Conversely, some warm-water species expand into more northerly regions. For instance, off the U.S. West Coast, the influence of El Niño and marine heatwaves has caused the fishing grounds for market squid to expand northward, creating new fisheries in Oregon and Washington; production in 2020 showed rapid growth compared to 2015.
Insights: Response and Management Amidst Changing Conditions
To address the uncertainties brought about by El Niño, fisheries management requires adjustments:
- Dynamically adjust fishing strategies: Management authorities need to dynamically adjust fishing seasons and limit fishing effort based on near-real-time monitoring data to respond to the spatiotemporal fluctuations of fishery resources.
- Strengthen disaster preparedness in aquaculture: Fish farmers must prepare for disasters such as extreme heat, torrential rains, and red tides by stockpiling emergency supplies, enhancing water quality management, and reinforcing facilities.
- Integrate climate factors into management frameworks: Future fishery resource assessments and sustainable management plans must treat climate variability-such as El Niño-as a core variable and establish more comprehensive coupled "climate-physical-ecological" analysis models.
While El Niño is part of the natural climate system, the fluctuations in fishery resources it triggers serve as a profound reminder of the vulnerability of marine ecosystems and the importance of implementing adaptive and precautionary fisheries management in the context of climate change.