Humpback Whales in Alaska
February 26th, 2026 by Carl DWhere They Go, When They Come, and Why Spring Changes Everything
Every year, thousands of humpback whales make one of the longest migrations in the animal kingdom. They leave the warm breeding waters of Hawaii, Mexico, and the western Pacific and swim north. Some travel over 3,000 miles, one way. They don’t eat during the trip. They arrive hungry, and Alaska feeds them.
Understanding why they come here, when they show up, and where they concentrate is foundational to everything we do on our Hungry Whales Photo Tour each spring. It’s also the key to understanding why early spring in Southeast Alaska offers something the summer whale-watching season doesn’t.
Why Alaska
Humpbacks spend winter in tropical waters where they mate, give birth, and nurse calves. But tropical oceans are nutritional deserts for a baleen whale. There just isn’t enough prey down there to sustain a 40-ton animal that needs to eat a ton or more per day. So they fast. They live off stored fat for months, and by the time they point north they’re running on fumes.
Alaska’s cold, nutrient-dense waters are the payoff. The coastal waters of Southeast Alaska, the Gulf of Alaska, the Bering Sea, these areas produce massive concentrations of the small schooling fish and krill that humpbacks need. The whales feed hard during the Alaska months, building fat reserves for the next winter’s migration and breeding.
The whole cycle is driven by food. Alaska isn’t a destination for humpback whales. It’s a grocery store. The biggest one in the Pacific.
The Herring Connection
In Southeast Alaska specifically, one species holds the whole thing together: Pacific herring.
Herring aggregate in enormous schools in the protected waterways around Sitka, Chatham Strait, and the surrounding channels to spawn each spring. Timing shifts a bit year to year, but the peak generally falls late March through April. When the herring show up, the whales are right behind them.
This isn’t a casual relationship. Researcher Joseph Liddle tracked humpback whale abundance in Sitka Sound alongside Pacific herring spawning biomass from 1981 through 2011. The correlation between the two populations was 0.87. For context, that’s about as tight a link as you’ll find between a predator and its prey in the wild.
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