Humboldt State University Zoology professor Dawn Goley identified the whale that wandered into the Klamath River estuary on Wednesday as a gray whale and said it is not unprecedented for them to explore estuaries and rivers to find some food.
"Gray whales can become curious and go into the rivers and if they find something they like, they might stay," she said. "Sometimes there is abundant prey there. Often times they just come in and then leave. I'm pretty happy to hear this whale came in and left."
While the mouth of the river has a mix of saltwater and freshwater, Goley said the pure freshwater of the upstream areas is not the optimal place for whales to stay in for too long.
"Their physiology hasn't evolved to be in freshwater," she said.
The inability to stay in freshwater for long periods contributed to the death of the mother gray whale in August 2011.
"Her skin and physiology weren't able to accommodate being in freshwater," Goley said. "Her immune system was compromised. She died of combination of starvation and infection."
From the Yurok Tribe Facebook page:
A whale was spotted in the Klamath River estuary yesterday. Unlike the cetaceans that visited the river in 2011, this one stayed only briefly before heading back out to the ocean. In June of 2011, a mother gray whale and her calf entered the estuary. The calf stayed for a month before swimming back out to sea. Despite the Tribe's best efforts to encourage her to leave, the mother whale stayed in the river until she perished in mid-August of the same year. The Yurok word for whale is Heykw-sa'. This photo was taken by the Yurok Environmental Program's Merle Stevenson.