It's a question we island residents patiently put up with from May through September, the best time of year to see whales in local waters. Second only to, "What time do the whales come by?" the question "Where are the whales?" is a common one from not just tourists, but also among researchers, boat captains, naturalists, and all members of the whale-watch community. Often, the answer to the question in the summer months is something like "On the west side of San Juan Island" or "Swimming past Victoria" or "Near the mouth of the Fraser River by Vancouver, BC". The eighty-plus members of the Southern Resident Community of killer whales can travel up to a hundred miles a day, and without any of the animals being tagged it's visual spotting that finds them on a day-to-day basis. Despite a fleet of dozens of whale-watching vessels looking for whales during about 12 hours of every summer day, every morning it's sort of a whole new ballgame as to where they will show up after a nighttime's worth of traveling. More often than not in the summer months, they're somewhere within the Salish Sea, just taking occasional forays out the Strait of Juan de Fuca to the open ocean.
This year, however, the question, "Where are the whales?" has taken on a different meaning among the whale watch community. It's not just a curious question among hopeful whale watchers trying to track the movements of J-, K-, and L-Pods. It's a sadder, more anxious question this year because, quite simply, the whales aren't here.
It's true we've seen all members of all three pods in inland waters this season, but among those of us that watch these whales year after year, the consensus is something different is going on this year. They came back later than usual. They've been spending less time here. For a couple of bizarre weeks, the only whales here were the three members of the L22 matriline, something that has never happened before. But a hunch or anecdotal evidence isn't enough to prove something different is going on. Where's the data?
April and May used to be considered good whale-watching months here in the Salish Sea. According to
The Whale Museum's Orca Master data set, from 1978 to 2008, members of at least one of the three pods of Southern Residents were documented in inland waters in every single month of every single year. Often, this may have just been for one day, but some years J-Pod was around nearly every day in the spring. In 2009, for the first time on record, there were no sightings in the month of April. J-Pod returned on May 4th of that year. This year, again, there were no resident killer whales in the month of April and beyond until Js returned on May 15th. It was definitely a late return, but what's been going on since then?
Dr. Bob Otis, now a retired professor from Ripon College, has been collecting killer whale data at Lime Kiln Lighthouse for 23 years. Every year, from May 20th to August 10th, between the hours of 9 AM and 5 PM, he and his team of interns records data on every group of killer whales that passes within half of a mile of the lighthouse in any direction. While his data of course doesn't fully document every time the whales are in inland waters, it's a valuable long-term data set collected in the heart of the summer range of the Southern Residents, and its consistent collection provides a reliable benchmark. Bob generously provided me with his data, from which I extracted the following information showing the number of "whale days" between May 20 and July 27th (today) for each of the last 23 years. (A "whale day" is defined as any day when killer whales passed by Lime Kiln between the hours of 9 AM and 5 PM.) Click the chart to see a larger version.
The 17 whale days so far this year are by far the lowest since Bob started collecting data in 1990. In fact, it's less than half of the 20+ year average of 40 whale days (red line) in this time period and 12 days lower than any year on record.
So why haven't you been hearing about this? I've been asking myself the same question. The truth is, the whale-watching industry hasn't really suffered *too* much as a result of the lack of Southern Residents. The transient, marine mammal eating killer whales that are distant cousins of the fish-eating Southern Residents have been thriving, perhaps benefiting from a boon of the local harbor seal and Steller sea lion populations. I remember when I first started watching whales here, transients seemed like elusive creatures to me. It took years before I saw my first one. Now, I see them several times a year just from shore on San Juan Island, and the whale watch boats see them almost daily during certain times of year. Transients have been getting a lot of good press lately, including being
on the cover of a recent edition of the Seattle Times after wowing viewers right off the docks of Liberty Bay deep in Puget Sound, not far from downtown Seattle. The article mentions the Southern Residents, but says nothing about their scarcity this summer.
The sporadic transient orcas are still not a sure bet, but in addition there have been more humpback whales than usual, an abundance of lunge-feeding minke whales, lots of harbor seals with brand new pups, and fledgling bald eagles to help keep the tour companies occupied. I've heard it been suggested that local press may be staying away from the issue of the "missing" resident whales out of fear of driving away the tourists who flock here to see them. But there's no doubt in my mind: this is an issue that needs to be talked about.
More importantly than why it hasn't received more press is the underlying question of why the whales aren't here in the first place. The answer is most likely an obvious one: there's no fish here for them to eat.
Killer whales were formally thought of as generalist feeders as the species as a whole has been documented feeding on over 50 prey species. We now know that the Orcinus orca species is really a species complex made up of various ecotytpes of killer whales, each population specializing on a smaller subset of prey species. The Southern Residents have long been known to be fish eaters with a preference for salmon. In particular, they like Chinook salmon. Recent prey studies, like those conducted by Brad Hanson of NOAA's Northwest Fisheries Science Center, have shown just how strong this dietary specialization is. From genetic evidence from prey samples taken in the San Juan Islands, Brad's research team has found that not only do the Southern Residents preferentially feed on Chinook (despite being most likely to encounter pink, sockeye, and chum salmon), but they specifically feed heavily on Fraser River Chinook in June through August. The Fraser River, the longest river in British Columbia, enters the Salish Sea not far from the city of Vancouver and is one of the largest salmon-producing rivers in the region. Brad and other researchers have also conducted genetic analysis of fecal samples from the whales to help determine diet - in these studies, which look at percent composition of different prey species in the samples as opposed to frequency of occurrence with which the prey item is taken, Fraser Chinook dominate the diet by an even stronger ratio.
If you talk to a local salmon fisherman, they'll probably tell you the fishing has been great so far this year. The salmon are abundant right now, it's true - but they're pink salmon, the smallest of the local salmonid species. The residents probably preferentially feed on Chinook because they get the most bang for their buck: Chinook are the largest, fattiest salmon species. In the fall the whales switch to chum, the next largest species, but from genetic analysis of fecal samples, it doesn't look like the whales eat sockeye or pink salmon at all.
So how are those all-important Fraser River Chinook salmon runs doing this year? It's not a pretty picture. Here's the data from the
Albion test fishery near Fort Langley on the lower Fraser, which is able to monitor fish stocks returning to different regions of the river. This first chart shows the catch data (CPUE = catch per unit effort) through July 22 compared to the yearly average from 1981-2012:
The picture is even more striking when you look at the cumulative catch per unit effort from this year compared to the average over the same time period (taking note that unlike most years data was not taken this year from April 1-20 - but that seems to be a small contributor to the cumulative total):
So, with the salmon clearly not here, it's perhaps not such a surprise the whales are not here either. The question still stands, however: where are they?
There have been a few reports over the last few months of the Southern Residents off Tofino on the central west coast of Vancouver Island. Since the whales haven't looked particularly emaciated (to me) when they have been here, we can only assume (hope?) that they're finding an abundance of Chinook wherever they are hanging out, somewhere out in the open ocean. It sucks that we aren't able to see them more, but really what's most important is that they're finding enough to eat. As an admittedly potentially unrelated side note, we have yet to see any new calves born to any whale in any pod in 2013.
A fair question, too, is why the residents don't switch to eating pink salmon or other species when the Chinook are not abundant. The answer is a complicated one, but my best guess is that these highly social animals are extremely culturally rigid. Despite the stresses this population has been under from events like the live capture era (which resulted in maybe a third of the population being removed) they don't stretch their social associations to include transients, or offshores, or even Northern Residents. It seems no matter what happens, they will only associate with their own kind. There is also some kind of treaty, if you can call it that, in place that divides up the food sources, giving the two co-existing populations different shares of the food web: marine mammals for transients and fish for residents. They don't seem likely to break this treaty, even when it's a matter of survival, and it seems the rules are even more severe than we first thought, as not only will they not eat mammals but they won't even settle for less than Chinook salmon. One can only hope we don't find out what happens when we, as humans, push the Southern Residents to their cultural limits. They shouldn't have to choose (they may not be able to choose) between tradition and survival.
In the meantime, all I can do is witness what I see before me: that the whales are not here like they usually are this time of year. Witness, and pass on my observations to you, which hopefully you will then share with others. It's easy to gloss over this storyline because it's true, it's not a happy one. But that doesn't make it any less important to talk about.
