Transcript: Killer in Distress
Welcome to "On the Line", a NOAA Fisheries podcast.
Rich Press: It was forty years ago this month that the Endangered Species Act became law. That Act is a complicated piece of legislation, but what it boils down to is this: if a species is at the brink of extinction, or near it, we have to work to pull it back. And it doesn't have to be an entire species. If there's a distinct population within a species that's at risk of disappearing, the law applies to them as well.
Today's podcast is about the small population of killer whales that spends every summer around the San Juan Islands north of Seattle. They go there to feed on the runs of returning salmon that funnel through every year like clockwork. Unlike many other populations of killer whales that eat seals and other mammals, these ones only eat fish, and mostly salmon. Unfortunately for them, the salmon runs are just a fraction of the size they used to be.
This group of animals is called the Southern Resident killer whales, and they're a highly endangered population. Unfortunately, their numbers aren't rebounding, and scientists are working to figure out why.
Today we have Candice Emmons on the line. Emmons is a research biologist at NOAA's Northwest Fisheries Science Center and she works with Southern Resident killer whales. We also have Lynne Barre on the line. Barre oversees NOAA's recovery plan for these whales. The two of them talk about the threats the Southern Residents are facing, and about how new scientific information might help us help the killer whales to recover.
I spoke with Emmons first, and I began my interview with the obvious question…
So Candice, who are the Southern Residents? And how did they get that ridiculous name?
Candice Emmons: [Laughter] They’re a small—smallish population of fish-eating killer whales that spend a lot of time in the inland waters of Washington and British Columbia, primarily in the summer when they are following salmon runs that are returning to their rivers. And when they initially started studying them, they called them residents because they appeared to be resident to the area. As we’ve studied them more we’ve learned that residents are quite mobile. So those are kind of misnomers but they’ve kind of stuck around for lack of a better term.
Rich Press: Yeah. How’s the Southern Resident population doing?
Candice Emmons: Well, they kind of peaked in the mid to late ‘90s at around 100 animals, and then went through a decline, and in the early 2000s that piqued a lot of people’s interest and concern and a petition was presented to list them under the ESA.
Rich Press: The ESA?
Candice Emmons: The Endangered Species Act, and that was done in 2005. And since that listing they’ve hovered around 80 animals. They’ve fluctuated quite a bit, up to about 85 or 86, but right now they’re currently at 81 animals.
Rich Press: Gotcha. So the population either isn’t growing or isn’t growing as fast as you would like, is that right?
Candice Emmons: We’d like, yes—correct.
Rich Press: So what’s holding them back?
Candice Emmons: They have a lot of different potential threats. And the main risk factors for this population are prey availability and quality, toxins in their prey that accumulate in their blubber systems, and then anthropogenic effects of vessel presence, both large shipping and whale watching. And then they’re just a small population, so some of the demography is a little concerning. You know, they’re in an area with a lot of shipping traffic. One oil spill could be catastrophic because they are a small population.
Rich Press: You mentioned their prey. So is one hypothesis that they’re not getting enough to eat?
Candice Emmons: Well, not getting enough to eat, or that it’s becoming harder and harder to find so they have to travel further to find it. And it may not be the quality of prey or what they would prefer. So we’ve done a lot of research in this area, and they’re salmon eaters but they really prefer Chinook salmon, which is kind of the biggest, fattiest, you know, of the fish. So if there’s not enough of those they might have to choose less preferable prey.
Rich Press: So tell me a little bit about the science about how you figure out what they’re eating and where they’re going.
Candice Emmons: Well, one of the main techniques we use is we do prey sampling. So basically get behind a whale or a couple of—group of whales, and fortunately for us they are very messy eaters, and especially ‘cause they share their food quite a bit. So after they kill a fish a lot of times they leave behind scales or tissue samples, and then we can actually—our genetics lab here can actually tell us not just the species of fish they’re consuming, but the age and the river system that’s they’re from.
Rich Press: That’s amazing that of all the salmon runs out there you can figure out exactly which ones they’re keying in on. But how does knowing that help us to help the killer whales to recover?
Candice Emmons: Well, the first step in protecting the fish that they need is actually knowing what it is. We’ve actually found out that in the summer the Fraser River—not surprisingly; it’s one of the biggest river systems around here—but it’s really important to these guys. And the Southern Residents have become another stakeholder essentially in salmon negotiations for the Fraser River.
Rich Press: If we know that the killer whales are particularly dependent on a specific run of Chinook, what can we do to manage things in a way that would benefit the Chinook but also benefit the killer whales?
Candice Emmons: I can’t really answer that question, [Laughter] ‘cause I’m a scientist. I’m not a manager. [Phone dialing and ringing] I wish I could answer that question because there’s no simple answer, but you know, somebody like Lynne Barre would be a much better person to talk to that actually is on the management side.
Lynne Barre: Hello, this is Lynne.
Rich Press: Hi, Lynne. This is Rich Press calling from NOAA Fisheries headquarters.
Lynne Barre: Hi. How are you?
Rich Press: I’m great, thanks.
Rich Press: Well, I took Candice’s advice and I called Lynne Barre to ask her about this. Barre works on the management side of things.
Lynne Barre: Oh, okay. So I’m the lead for Southern Resident killer whale recovery, and so our office is in charge of consultation under Endangered Species Act to look at what are the impacts of different actions, including our own actions like managing salmon fisheries, on endangered species including the endangered Southern Resident killer whales.
Rich Press: So how does knowing which runs of Chinook salmon the killer whales are dependent on help us to help the killer whales?
Lynne Barre: From a management perspective, knowing which river systems the killer whale’s prey comes from is extremely important. There’s quite a few salmon recovery efforts underway, and if we can focus our efforts and get the most bang for the buck in implementing recovery actions that benefit both the salmon and the whales simultaneously, then we’re going to be most effective for recovery.
Rich Press: What does salmon recovery involve? What kinds of actions can we take?
Lynne Barre: Salmon recovery is a region-wide effort and we’re looking at things like harvest in commercial and recreational fisheries, we’re looking at hydropower dam systems, hatchery programs, and also habitat restoration for salmon spawning and rearing.
Rich Press: So what else are we doing to help the Southern Residents aside from salmon recovery? What other measures are we taking?
Lynne Barre: The Southern Resident killer whales are the focus of a strong whale watching industry from both the United States and Canada, and so in 2011 we put some new vessel regulations in place, and again, these were very well informed by the scientific information we had on how vessels might be changing the behavior of the whales, about how sound from the vessels can effect the echolocation and communication of the whales—these are acoustic animals, they use sound. We used all that information to develop a 200-yard approach rule, and a prohibition on having vessels in the path of the whales. Two other big pieces of our program include oil spill planning, so that’s something we’re doing for killer whales, and then another key part of our program has been to fully investigate any stranded killer whale. It’s rare that we get a dead killer whale on our beaches, and so when we do have those situations we get a chance to look at, are whales that go missing from the population, are they skinny, are they not getting enough to eat. Is there a disease that we’re worried about, is it something like a vessel strike that might have caused the death, and so those are really critical scientific evaluations to help inform what we know about the whales, and what we can do to recover them.
Rich Press: Before I go, I just want to share with you something interesting that I learned while working on this podcast. In these fish eating populations of killer whales, the offspring never leave their mothers. The animals live together in groups called pods, which are like extended families that all tie back to an older female. And because they're very long-lived—they can live to 80 or 100 years old—there can be as many as four generations of them living together. I found this interesting because in all the animal kingdom, there are just a few animals that continue to live long after they've stopped reproducing. There's us, of course, a couple of other primates, there's elephants, and then there's these whales. That's just about it. I asked Emmons why she thought the killer whales evolved longevity, and she said that she thinks the old ones pass knowledge and culture down through the generations. She said, think about the life history of salmon, all those different species, and all those different runs, each one following its own particular rhythm. It's incredibly intricate clockwork, and you have to have some wise old whales with long memories if the group is going to thrive in that environment. Hopefully, with help from the Endangered Species Act and from scientists like the ones you heard from today, the Southern Residents will soon thrive again.
As always you can get more of this story on our podcast page, that's www.fisheries.noaa.gov/podcasts. There you'll find some awesome photos of killer whales taken by our scientists in the field. You'll also find links to the Northwest Fisheries Science Center website where you can read more about killer whale recovery and about the science, and the scientists, behind it.
Thanks for listening. Join us again next time for more stories about ocean life and ocean science. I’m Rich Press, and you’re listening to "On the Line".
You have been listening to the NOAA Fisheries’ podcast, "On the Line". Join us next time for a first-hand look at the people and the science behind managing our nation’s fisheries. For more information, visit NOAA Fisheries at www.fisheries.noaa.gov.
"On the Line" is a production of the NOAA Fisheries Office of Communications.