you can’t eat extinction

Pretty good string of articles from Mr. Hume these days — salmon are getting some mainstream press. Good to see…

Mark’s article today in the Globe, is based on an article by Elizabeth Pennisi in Science magazine:

Some Salmon Can Take the Heat

The Chilko sockeye is the Michael Phelps of salmon. Once a year, it swims 650 kilometers up British Columbia’s Fraser River, fighting rapids and strong currents, to reach a spot where it can lay and fertilize its eggs. New research reveals that the fish is well-adapted to this journey—it has a bigger, better heart and uses oxygen more efficiently than do other local salmon. And thanks to these attributes, the Chilko sockeye may be more likely than these other fish to survive a warming world.

Not all of the Fraser River’s salmon swim as far as the Chilko sockeye. Some stay relatively close to the coast; others swim a bit farther upstream to spawn. There are so many different migration distances that the fish have split into 100 distinct populations—one of which is the Chilko—with different swimming behaviors and body types.

Hot summers take a toll on these migrations. In 2004, for example, 80% of some salmon populations died of heat stress before reaching their spawning destinations. Water temperatures in the Fraser River have risen 2°C in the past 60 years, and, with global warming, researchers expect even bigger die-offs to come. Erika Eliason, a graduate student at the University of British Columbia, Vancouver, in Canada, wanted to know whether different populations of Fraser River salmon were better than others at handling the heat.

I think this is called local adaptation and demonstrates the importance of biodiversity… not to mention the scary stat that 80% of some salmon populations die en route in the river. First, they dodge all the fisheries, seals, orcas, and pollution of the lower Fraser (not to mention years of the North Pacific…) — then they die en route, simply because the water gets too warm.

It will give those of you comfort to know that pre-season forecasts for this year are looking dismal; however, the Department of Fisheries and Oceans is still floating around various potential scenarios that include harvesting up to 50% of some runs. The hearty Chilko run will most likely be one of those runs with targeted fisheries.

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Mark Hume in the Globe today:

Sockeye salmon at risk of overheating due to climate change: study

Sockeye salmon in the Fraser River are facing such critically warm water in the summer that populations will either have to adapt or die as climate change pushes temperatures even higher, according to new research at the University of British Columbia [by Erika Eliason].

With oceans, lakes and rivers warming worldwide, the study holds a warning that fish stocks are facing increasingly dire environmental challenges…

…What Ms. Eliason found was that sockeye, which migrate up to 1,200 kilometers in the Fraser, are already “near their upper limit” for warm water and any further increases could lead to the disappearance of some populations.

Ms. Eliason said it isn’t known how long it takes a population to change physiologically to adapt to environmental conditions – and it might not be possible for any of the populations to change fast enough to survive in the long run.

“The current challenge is determining whether the rates and extents of physiological adaptation for Fraser River sockeye salmon will allow them to adapt quickly enough to cope with the current warming trend,” concludes the paper.

The Fraser has warmed by about two degrees over the past two decades and the trend is expected to continue. The river is usually over 19 degrees in the summer, and often hits highs of around 21.5 degrees.

“They are all near their upper limit. . . 21.5 degrees C is already higher than the optimal temperature for every single population in the Fraser,” she said. “There is not much room there, for anybody.”

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But have no fear, the bumpf-ologists have this well under control… this is a quote from Canada’s Wild Salmon Policy (WSP); it has an entire section on the Precautionary Approach:

The definition fronted in the Policy suggests:

Precautionary approach. When used in an advisory context in support of decision-making by the Government of Canada, this term conveys the sense that the advice is provided in situations of high scientific uncertainty. It is
intended to promote actions that would result in a low probability of harm that is serious or difficult to reverse.

There’s the problem!

The precautionary approach “will be used in an advisory context in support of decision-making by the Government”…

That means that the precautionary approach and science are simply advising political decision.

What else guides political decisions?

Money.

Money in the form of campaign and party contributions and lobbying and that exact science of “economics”… (you know that field that the Prime Minister of last week has specialized in…).

Which ones do you think carry the most weight?

As as starting point, one could go ask the once busy cod fishermen of the East Coast…

The only problem is that you can’t eat extinction… and extinction certainly doesn’t pay the bills.

3 thoughts on “you can’t eat extinction

  1. Brian

    Quote: “Hot summers take a toll on these migrations. In 2004, for example, 80% of some salmon populations died of heat stress before reaching their spawning destinations.”

    The only thing that does not get mentioned in all this (and in the inquiry recently) is that this 80%, 70% and 60% loss is likely based on the assumption that the Mission numbers are correct. This would be a pretty big assumption in some years.

    Although I do not necessarily disagree with Scott Hinch’s hypothesis based on how the Fraser is heating up and the toll it takes on migrating salmon, it is also equally important to remember that there can be discrepancies between what Mission counts and what is counted on the spawning grounds. The difference is assumed be enroute loss. I personally do not agree that this difference is entirely enroute loss.

    For one thing, millions of Sockeye that die enroute between Mission and the spawning grounds do not just vanish or end up on the shorelines with anyone noticing. It is true that dead Sockeye can sink to the bottom of a deep pool in the river or in a lake, but many do eventually come back to the surface. Furthermore, enroute loss is also based on the assumption that radio tagged Sockeye behave the same as non-radio tagged Sockeye. Because a radio tagged Sockeye holds in a side channel of the mainstem Fraser or swims into a pool in distress state does this mean that other non-tagged Sockeye are acting the same way? Maybe….but maybe not.

    Last season I believe Mission was pretty close in its estimates, but there are other years where the possibility of large discrepencies could exist – especially if their are co-migrating pink salmon (on years when they are abundant). Trying to break out those two species is one of the limitations of traditional split beam technology (in my opinion). In addition, last season we saw a fairly large descrepancy between the test fisheries and what ended up on on the spawning grounds. These were unprecedented numbers for the test fisheries using lines modelled from historic catch and timing. I believe the test fisheries do the best they can under the circumstances; however, there were likely errors in estimating what was out there, so it is not inconceiveable that differences are due to other factors other than enroute loss.

  2. Brian

    Quote: “The Chilko sockeye is the Michael Phelps of salmon. Once a year, it swims 650 kilometers up British Columbia’s Fraser River, fighting rapids and strong currents, to reach a spot where it can lay and fertilize its eggs. New research reveals that the fish is well-adapted to this journey—it has a bigger, better heart and uses oxygen more efficiently than do other local salmon. And thanks to these attributes, the Chilko sockeye may be more likely than these other fish to survive a warming world.”

    Chilko Sockeye have the highest migratory elevation change than other Fraser River Sockeye to my knowledge. Chilko Lake is 1285m above sea level, so that is a pretty decent climb from sea level to Chilko. In addition, Chilko Sockeye are very topedo-shaped and perhaps a little smaller when compared to other Fraser River Sockeye stocks like the Adams and Upper Pitt. To help save energy during their migration, Chilko Sockeye tend to migrate closer to the Chilko river banks, taking advantage of slower water velocities and less turbulant water. So close that they can be within a few feet of the shore. Chilko Chinook, on the other hand, will tend to stick to the middle of the channel in the higher velocity flows. As a side note, it is this spatial separation of species that makes DIDSON (Dual Frequency Identification Sonar) very successful at Chilko.

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