I’ve watched orcas for the better part of a decade, and honestly, the thing that gets me every time is how they just know.
The southern resident killer whales—those black-and-white behemoths cruising the Salish Sea between Washington and British Columbia—time their movements with an precision that borders on eerie. They’re tracking Chinook salmon, specifically, following the runs as these fish muscle upstream to spawn. The whales arrive in inland waters around May or June, just as the salmon start their journey, and they stick around through September, sometimes October if the runs hold out. It’s not random wandering. Researchers have documented this pattern for roughly 40 years now, give or take, using photo-identification of individual whales by their dorsal fins and saddle patches. The orcas are basically operating on a calendar that’s written in fish.
But here’s the thing: the salmon aren’t always where they used to be. Climate change, dam construction, overfishing—all of it has hammered Chinook populations. The Fraser River run, which used to be a reliable buffet, has crashed in recent years, and the whales are feeling it.
When the Dinner Bell Stops Ringing in Predictable Waters
Wait—maybe I’m getting ahead of myself.
The northern resident killer whales, a different population that hangs out further north along the British Columbia coast and into Southeast Alaska, they follow a similar playbook but with different salmon stocks. They’re keyed into pink salmon runs, chum runs, whatever’s abundant in their range. Scientists have tracked them moving between Johnstone Strait, Queen Charlotte Strait, and out to the continental shelf, distances of hundreds of miles, all choreographed around where the salmon are running at any given moment. Dr. Lance Barrett-Lennard from the Vancouver Aquarium once told me—well, not me personally, but in a paper I read—that these whales have cultural knowledge passed down through matrilines. The grandmothers teach the mothers, who teach the calves, which rivers to visit and when.
Turns out, this isn’t just about food. It’s about survival wrapped in tradition.
The transient killer whales (now called Bigg’s killer whales, after researcher Michael Bigg) don’t really bother with salmon at all. They eat marine mammals—seals, sea lions, even other whales. Their migration patterns are way more erratic, less seasonal, because their prey doesn’t follow the same predictable spawning cycles. I used to think all orcas were basically the same, just different neighborhoods, but the dietary split has created entirely separate cultures. The fish-eaters don’t even socialize with the mammal-eaters. They speak different dialects, hunt differently, move differently.
The Genetic Memory Encoded in Dorsal Fins and Failing Rivers
So what happens when the salmon runs collapse?
The southern residents are starving. Like, actually starving. Necropsy reports from dead whales show emaciation, pregnancy failures, weakened immune systems—all consistent with chronic malnutrition. The population dropped to 73 individuals as of the last count I saw, down from a high of 98 in the mid-1990s. They’re still showing up in the Salish Sea on schedule, because that’s what their culture dictates, but the food isn’t there. Some researchers have documented them ranging further south along the Washington and Oregon coasts, possibly searching for alternative salmon stocks, but it’s not clear if they’re finding enough. One whale, designated J35 or Tahlequah, carried her dead calf for 17 days in 2018, pushing it through the water in what looked for all the world like grief. The calf had probably died from malnutrition, either in utero or shortly after birth.
I guess it makes sense that a species this intelligent would suffer in ways that look painfully familiar.
The orcas’ migration isn’t just a biological imperative—it’s a story they tell themselves, passed through generations, about where to go and when. But the world is rewriting that story faster than they can adapt. The salmon runs are the chapters, and we’re tearing out pages. Meanwhile, the whales keep showing up, keep listening for a dinner bell that rings quieter every year, keep teaching their young a map that’s becoming obsolete. It’s not that they can’t learn new routes—there’s some evidence they’re trying—but cultural inertia is strong, and salmon declines are happening faster than generational knowledge can shift. Anyway, we’re watching an extinction unfold in real time, measured in missed meals and empty nurseries.
And here’s the uncomfortable part: we definately know what needs to happen. Restore salmon habitat, remove dams, limit fishing quotas, reduce vessel noise that interferes with echolocation. But knowing and doing are different things entirely.
