Wakefield Symposium moments: Impacts of a changing environment on the dynamics of high-latitude fish and fisheries

Anchorage 5/13/17

I’m getting my comments together complimenting the Scientific Steering Committee for the great job they did putting together the program for this year’s 31st Lowell Wakefield Fisheries Symposium. I think the scientists and fisheries managers who attended got exposed to an unaccustomed variety of views that at times pushed them out of their comfort zone and allowed all of us at least peeks and at times revealing analyses of fish and marine ecosystem biology in other parts of the world. This was due to the diversity of the program, particularly the invited speakers.

Today I’m writing up a few of the beautiful moments those visitors provided. Economist Brooks Kaiser of the University of Southern Denmark and her colleague Linda Fernandez of Virginia Commonwealth University were economists brought to the conference as part of the trendy effort to incorporate social science in the climate change discussion. I’ve never considered either psychology or economics to be very scientific, but younger investigators like these two are forcing me to revise my opinion. Kaiser presented on the issue of the shrimp fishery on the west coast of Greenland, which accounts for more than half of the country’s total fisheries. As the fish stocks move north, so do the processing plants, but there is less population up there and a more rugged coast with no infrastructure, so what is going to happen if the northward movement continues is speculative. Fernandez looked at Opilio crab stocks moving northward into the Barents Seas between Iceland and Russia as they move out of Canadian waters. This as a population of Red King Crab introduced by Russia expands to the west, both increasingly in a “donut hole” or, as they call it, “loophole” in international waters. Legal cases and treaty efforts ensue. But what I really enjoyed was Kaiser’s participation in the closing panel discussion, in which she told the scientists they needed to stop being afraid to confess their uncertainty. “In economics, we’re used to dealing with uncertainty. Policy people want to know about risk, and uncertainty is a part of risk, and we can calculate that.”

It was also fun to watch her take on quota shares, so beloved by some elements of the conservation community, but not by her, or by most locally based fishermen, who have watched the quota shares get too expensive to buy and end up in the hands of absentee owners and large outside operations. Not to mention what happens when the processors end up owning the quotas and can dictate prices to the fleet. And then there was her response to a question about the prospect of triaging populations at risk – whether maybe it was best to give up restrictions and management expense sometimes in the interest of putting resources where they will do the most good. You can imagine the howls of reaction. But Kaiser cooly said “I’m not sure there should be any limit on that snow crab fishery (that has arrived in the Barents.) It’s invasive to start with. Maybe not having a quota would slow them down some.” Oh, bold and refreshing heresy!

The participation of German fish physiologist Hans-Otto Portner was sturdy and valuable. He listened closely to every session, and often had very pointed questions. This is the man in charge of writing a major part of the IPCC report. Portner was rigorous, often seeking to tie the high-flying computer modelers down to hard physical data, and of course physiological data. The response of fish to higher temperatures is complex. On the one hand they tend to get bigger, on the other hand their metabolic rate goes up and they have to get more energy from their food. Plus most marine species have ranges of thermal tolerance that some can migrate to stay within and some can not and maybe they have the capacity to evolve or maybe they do not. The computer models do not get to a lot of these places – these physical environment differences at a fine scale. Sometimes they don’t even realize the animal they are plotting is dead. In other words we sometimes have actual ghosts as products of a scientific culture that too often tends to disbelieve things that can’t be made to happen in laboratories or inside computers.

The limits of modeling were also taken up by another invited speaker from Germany, Christian Mollmann, of the University of Hamburg. I’m not sure anyone entirely caught his drift, but he brought up catastrophe theory as he discussed regime shifts in the Baltic Sea, a water body that is enclosed except for a bottleneck where Denmark juts up toward Sweden. This creates a difference between north and south, including a gradient of salinity. There are substantial issues here, such as runoff from hog farms, overfishing, as well as the changing climate. In a nutshell, here is what happened. Overfishing caused the Atlantic Cod stocks to collapse in the 1980’s, but in 2005 Cod started showing up again. It was literally declared a “miracle,” and the fleet went right to work, fishing conservatively, as directed by regulators. Media accounts were optimistic. Scientists were optimistic. But by 2012 the Cod were gone again. “We don’t know what happened,” Mollmann said. And all the computer models anyone has tried have failed to find the drivers of this collapse. Best guess: as catastrophe theory says, there can be a point of development where there is instability and things can tip at that point irrevocably.

So of course during the panel, the regulators were talking about how they needed to find the “tipping points.” Keep trying, folks.

 

 

 

 

2 Comments

  1. David Otness says:

    Thumbs-up.
    I wasn’t aware of the opies’ out-migration.

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