A juvenile gray whale that captured the attention of Washington state residents by swimming an unexpected 20 miles up a small river has been found dead. This tragic discovery has raised concerns among marine mammal experts, who speculate that hunger drove the whale to seek new hunting grounds amid a declining population.

The whale’s body was located on Saturday near Raymond, Washington, in the Willapa River, which connects to the ocean via Willapa Bay. Currently, several gray whales are passing through the bay during their 5,000-mile spring journey from Baja California, Mexico, to their feeding territories in Alaska.

John Calambokidis, a research biologist with the Cascadia Research Collective, reported to The Associated Press that since 2019, gray whales in the eastern Pacific have been struggling with diminishing food supplies in the northern Bering and Chukchi seas off Alaska’s coast. This situation has forced some whales to explore new areas for sustenance.

“Gray whales are facing a major crisis,” Calambokidis stated, “and the heart of it seems to be their difficulty in accessing prey in the Arctic.”

In light of this situation, the National Oceanic and Atmospheric Administration (NOAA) Fisheries agency declared an unusual mortality event for these eastern gray whales, spanning from late 2018 to late 2023. During this period, 690 gray whale strandings were recorded from Alaska to Mexico.

NOAA Fisheries investigators have determined the preliminary cause to be “localized ecosystem changes” in the whales’ sub-Arctic and Arctic feeding zones. These changes have resulted in reduced food availability, leading to malnutrition, lower birth rates, and increased mortality among the whales.

Officials believed the population was rebounding, but the most recent count from 2025 instead showed a continuing decline. The federal agency estimated there were about 13,000 gray whales, the lowest count since the 1970s.

“A lot of these gray whales are looking very emaciated, very thin,” Calambokidis said.

Their migration north is typically the most challenging period for gray whales, the longest they’ve gone without eating, forcing the animals to use up their nutritional reserves.

“When that happens, you often see gray whales in a more desperate search for new areas to feed,” Calambokidis said. “That’s the most likely context for this whale.”

Researchers will attempt to examine the whale, possibly as soon as Monday.

It entered the north fork of the Willapa River on Wednesday, via a bay about 185 miles (298 kilometers) southwest of Seattle. Residents gathered on bridges along the river just to catch glimpses of the massive mammal and flooded social media with photos and video of it expelling air through its blowhole.

While the gray whale appeared thin, it was behaving normally and didn’t appear to have any injuries, the nonprofit Cascadia Research Collective said in a Facebook post.

The organization was giving the whale time and space to leave the river on its own, but when researchers attempted to find it Friday, the animal had traveled further upriver into waters that were unnavigable by boat, Calambokidis said.