When you hear "El Niño," you probably think weather. Underwater, it's one of the biggest food events on the planet, and NOAA says this year's could be the strongest ever recorded, with an 83% chance of a historic event this fall. We follow it from the bottom up: weakening trade winds shut down the upwelling that feeds the Pacific, phytoplankton decline, and Peru suspends the world's largest fishery after warm water fills the nets with young anchovy. We look at what past strong El Niños did to Galápagos penguins, flightless cormorants, marine iguanas and sea lions, and how predators like tuna and hammerhead sharks shift. Then we follow the anchovy to fishmeal, fish farm feed and the farmed salmon in your grocery store, and to the fishing families who feel it first. And closer to home, we cover what Canada's climate scientists expect for our coasts, from salmon off BC to sea ice and storm surges in Atlantic Canada.
Then we follow the biggest animals in the ocean. In the El Niño years of 2015 and 2016, humpback whales went almost silent on underwater recorders in the Southern Ocean. Off Ecuador, part of the humpback population appeared to skip the trip to the breeding grounds in strong El Niño years, which threw off whale counts. We cover research from Costa Rica, a humpback that switched oceans, and 25 years of sightings off California showing how El Niño changes when whales arrive, and why that raises the risk of fishing gear entanglement.
Next time someone calls El Niño a weather story, ask: what is it doing to the food? And next time you see a headline about "missing" whales, ask what happened to their food.
Takeaways:
NOAA says El Niño is still strengthening, with an 83% chance of a historic event this fall. Parts of the eastern Pacific are more than 4°C above normal.
El Niño weakens the trade winds and shuts down upwelling, cutting off the nutrients that feed phytoplankton at the base of the food web.
Peru suspended its anchovy fishery, the world's largest, in 2026. The first season caught only about a quarter of its quota.
Past strong El Niños crashed Galápagos penguin populations by 77% (1982–83) and 65% (1997–98).
Peru's anchovy becomes fishmeal and fish oil, about 20% of the world's supply, and most of that feeds fish farms.
Canada's climate scientists say this El Niño is virtually certain to be very strong, with impacts for BC salmon, Atlantic sea ice and coastal storms.
Humpbacks were virtually absent from Southern Ocean recordings during the 2015 and 2016 El Niño years.
El Niño can change when whales arrive and whether they complete their migration, which affects whale counts and entanglement risk.
What you can do: follow the food this winter. Watch for fishery closures, seabird die-offs and wildlife in unusual places, and report entangled whales to your local marine mammal response network.
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