by Nick Escalada
Humboldt is a refuge for old-growth redwoods and progressive culture, as well as a seasonal pit stop for the largest animal on the planet. Blue whales are migratory marine mammals that occur in all the world’s oceans — except the Arctic — throughout the year. They convene with their grey and humpback cousins on the Northern California coast from late summer to early fall to feed, using their comb-like baleen plates to sieve krill and plankton from the water.
“All baleen whales have two parts of their lives: one part where they’re feeding extensively, and then the other part where they hardly feed and give birth and breed and then come back and feed,” said researcher Dawn Goley, Director of the HSU Marine Mammal Education and Research Program. “The animals up here are feeding where the cooler water is, which is going to be the most nutrient-rich, and it’s going to be the most productive with krill.”
The visiting whale community is en route to the warm lagoons of Baja California and Costa Rica to breed, fueling up for the journey in aggregations of 20 to 100 hunters. Goley and the Cascadia Research Collective are monitoring the pods with combinations of photo identification, suction-cupped satellite tags and aerial drone footage.
“We take photos of their dorsal surface, of their little tiny dorsal fin, and that’s individually identifiable,” Goley said. “So, we’re trying to track the blue whales that we see here and see if they’re coming back every year. And we do have some that come back every year, that are that we’re familiar with, and then others that we aren’t that familiar with, but we keep track of them in a collaborative catalog that’s shared between groups.”
Like many marine animals, behavioral data on blue whales is relatively sparse and scientists are still discovering new strange tendencies today. A major focus of Goley’s research is the methods the animals use to hunt the four tons of krill needed to sustain their up to 200-ton bodies. Her teams use special equipment to determine things like the structure of krill formations, how deep the whales dive and how quickly they turn.
“They can look to see how whales are actually foraging in this sort of three-dimensional prey cloud under the surface,” Goley said. “And then you can have a drone overhead that is looking at sort of the dimensions of the school of prey. Sometimes you can see the krill at the surface. Sometimes you can’t, but you can see how the whale is moving and feeding on the prey down there.”
Blue whales are currently listed as endangered by the International Union for the Conservation of Nature. The species has been on a steady rebound since the commercial whaling industry dissolved in 1966, but they continue to be threatened by warming ocean temperatures, which both diminish natal habitat and decimate krill populations.
“They were really heavily hit by the whaling industry because they’re big and they’re kind of slow, and they were easily targeted by whaling,” Goley said. “But I think that they’ve been recovering really well.”
A telescope at Sue Meg or another good vantage point might catch a breach from a humpback whale. Blue whales are more illusive, and require setting out on the water in a vessel for a good view. Krill feeding grounds can exist anywhere along the coast, but sightings often occur off of human-accessible harbors like Humboldt Bay, Trinidad and Crescent City.
While most distinguishable by their enormous size, blue whales have comparatively slender bodies and tiny dorsal fins. They have mottled bluish-grey skin that can be hard to make out from the water from a distance, but a blubbery mass the length of two school buses is unmistakable otherwise. Encountering a being of this stature might be intimidating, but it’s an increasingly rare honor in the scientific world.
Nick is the news editor at The Lumberjack and studies wildlife and journalism with the goal of spreading his love of nature through media. Chat with him at ne53@humboldt.edu!
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