Thanks to Scoble, I've gotten a lot of traffic through my site recently. Andrew Watt liked my piece about Microsoft Research, though he saw "orcas" in the header for my weblog and assumed it referred to the future version of Visual Studio sharing that codename.
Actually, it doesn't. It refers, instead to orca whales, and in particular to the Southern Resident population which live around the San Juan Islands.
You see, human beings have been rather unkind to the Southern Residents over the past 40 years. It started in the 1960's, when several adolescent males were captured and sold to marine parks throughout North America. First of all, that's cruel; orcas are social animals that live and communicate in pods of 20+, and can easily swim up 100 miles a day. To isolate them in a small tank in a marine park is inhumane.
Second, imagine what would happen to a fairly isolated tribe of humans if you forcibly removed a substantial portion of the adolescent male population in a short period of time. Normal attrition would continue through age and other circumstances, but without the usual breeding there are far fewer babies and it would take a very long time for the population to recover.
Orcas are highly intelligent mammals with a complex social structure. To the best of our knowledge, the Southern Resident orcas are a genetically isolated population and do not interbreed with other populations. Thus through the 1970's and 1980's the southern resident orca population saw a very slow recovery, from a low point of 71 in 1974 (between 1967 and 1972, 34 orcas were captured and removed) to a high of 96 in 1993.
Then in the mid-90's we switch to Chapter 2 in this unfortunate saga that extends to present day. To understand this part, I need to lay out a few more data points for you.
1. In the 1960's, humans dumped a large quantity of a toxic chemical called PCB into the waters of Puget Sound, severely polluting the ecosystem. It worked its way up through the food chain, eventually ending up in the salmon that the orcas eat. The good news is that the PCB's have largely been cleaned up. The bad news is that it's still in the blubber of many of the orcas from having consumed tainted fish decades ago.
2. In the 1970's and 1980's, the salmon runs of the Puget Sound area were overfished, decimating the salmon runs almost to the point of extinction. In the past couple of years they have started making a comeback, but they are still severely depleted and many species of salmon are listed as endangered.
3. Southern Resident orcas' diet consists almost exclusively of salmon. They actually hunt salmon, often in packs; they will surround a school and herd them towards other orcas until they are trapped and can be consumed. They can do this quite effectively by using their echolocation capabilities (the same way commercial fishermen use sonar to spot schools of fish).
4. The San Juan Islands are known widely for their natural beauty. They are a very popular vacation spot in the summer. They are otherwise a small and fairly isolated comunity. As such, tourism is a significant contributor to the local economy, and probably the largest single contributor.
5. The Southern Resident orcas can reliably be found around the San Juans from May through September. The rest of the year, they head out into the Pacific Ocean to whereabouts generally unknown, and make only brief appearances in Puget Sound. This happens to correspond with the height of the tourist season.
6. Beginning in the mid-90's, there has been a boom in eco-tourism in the Pacific Northwest, including whale-watch boats. What began as a small operation has steadily grown in size to dozens of companies operating out of Victoria, Bellingham and the San Juans. The whale-watch industry is now well organized, with coordinated radio communications relaying the position of orca pods between operators. There are also whale-watch floatplanes, which can spot the orcas from the air. Many of the whale-watch operators guarantee that their customers will see whales; they can do this because collectively the whale watch operators know where the pods are all day long.
OK, let's put the pieces together.
In 1996, the southern resident orca population began a rapid decline. There has been enormous debate about the cause of this steep dive. There is a general belief that decline in salmon runs, combined with PCB contamination in their blubber, are major contributors -- i.e. with less food, the orcas have been required to use up some of their stored blubber which has poisoned them. There has been a notably high infant mortality rate in the southern residents, which is attributed at least in part to PCB-contaminated mothers nursing their babies.
There is one more theory that has been floated as to what has been going on. It certainly has not gone unnoticed that the population decline correlates with the rise in whale-watch boats. A theory now being proposed is that constant boat noise has exacerbated the salmon/PCB problem in a couple of significant ways:
- the noise from the boat engines actively interferes with the orcas' echolocation, making it much more difficult for the orcas to hunt for food.
- the boat engine noise also scares away fish, reducing the food supply.
- The whale-watch boats follow the orcas constantly, 5 months of the year, from dawn to dusk. This has raised their stress levels significantly. Imagine what it would be like to have a fire engine with its sirens blaring follow you around all day, every day -- that's what it's like for the orcas. And recall that water is an excellent conductor of sound...
An organization called the Orca Relief Citizens Alliance has funded some scientific studies on the orcas and boat noise. One study showed that the noise from boat engines degraded the effectiveness of orca echolocation by as much as 95%. Another showed that in the presence of whale watch boats, the orcas swim further and faster, and have higher respiration rates (they are mammals, and thus need to surface to breathe, so you can count their respiration quite easily). They are literally trying to get away from the boats, and exerting more energy in the process -- thus requiring more food. Combine this with the scarcity of salmon, their interference with their echolocation and thus their hunting ability, and the PCBs in their blubber... well, you get the picture, and it's a very bleak one indeed.
This is a politically charged issue, both locally nad nationally. Canada has listed the Southern Resident orcas as endangered. The US has refused to do so, thus limiting their protection under laws. So much of the economy in the San Juans is either directly or indirectly dependent upon tourism and ecotourism, that it is no surprise that there is a well organized opposition to these studies and the interpretation that the whale watch industry is contributing to the decline of the orcas. The Bush administration, apart from their usual pro-business anti-environment policies, also has a pro-military reason to oppose further protection for the orcas: the Navy has been trying to push through a new active sonar system far louder than any previous ones that has been shown repeatedly to cause significant damage to echolocating marine mammals. Last summer, the USS Shoup turned on its active sonar system in Puget Sound, sending the orcas into a frenzy and beaching several marine mammals. In the San Juans, the trade association of whale watch operators publicly touts the educational benefits of ecotourism, raising awareness of the orcas' plight (true, though you could argue at a very high cost). They also note that they have voluntary rules for their member companies about minimum distance to stay away from the orcas. But they are indeed voluntary, and since more than half the fleet is based in Victoria and doesn't belong to their organization, it's hard to argue that it does a lot of good to argue for voluntary self-policing.
I think this is a case where the intuition follows the science, and a straightforward application of Occam's razor would conclude that the whale watch boats are indeed harming the orcas. But it's worth pointing out that in the realm of science, the protocol is that you conduct experiments, publish your findings and conclusions, and let the open research community review and replicate them. It isn't proven until you've been through the whole cycle, and the O.R.C.A. studies have not been replicated.
Which leaves us with a very good question: with a strong suspicion, and early evidence, that the whale watch industry is harming the orcas, should strong limits be placed on it? Even if it will severely depress the local economy? Even if the evidence is not yet conclusive? There are no easy answers here. My answer would be yes, but the implications are huge and the consequences are grave.
Some more good reading: here and here and here.
8:33:23 PM  ; ;
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