Herring Scrap 20

Imagine that you have been asked to estimate the number of herring in a body of water at a given time. How do you go about it?

Pause here. Think about it. They’re pretty quick. They’re pretty small. They migrate. They ball up. They spread out. They scatter. They go deep. They go shallow. And the body of water in question features a few hundred miles of shoreline, all islands considered, some really deep bits, a lot of coves and bays and channels and inlets.

You might look at the problem and protest, saying it’s impossible to count small migratory fish in coastal waters, let alone multiple aggregations of them. But then you look closely at the contract, and yes, it says right there, very clearly: you have to. You have to find a way to count them! Otherwise the fishing can’t be justified, and if the fishing can’t be justified, then your job—  Don’t look at me like that. Just count the damn fish.

It might all seem overwhelming.

Or maybe not: you might think that it seems like an approachable problem with the right technology and knowhow.

Maybe you need the money and you’re just going to show up, try hard, do your best.

Or you might have some questions right off the bat, or after you’ve had a chance to think about the problem a little bit:

How much time do I have?

Do I have a team?

Do we have a boat? A plane?

Do we get to use cool gizmos?

How much money do we get to spend?

What are the boundaries?

Why do we want to know?

How will we know we’re successful?

                                        Nets! We need nets!

You might ask:

What do we already know?

****

Herring enumeration isn’t simple and before the 1940’s nobody had presumed to try – certainly not in Alaska.

Nobody had tried because it’s a ridiculous and generally unproductive thing to try.

Even so, courtesy of industrial logics, such a count has become the central obsession of ADF&G’s program in Sitka Sound.

How’d we get here?

***

In the Alaska Supreme Court hearings that I wrote about in scrap#18,  the justices reviewed pertinent elements of the history of the sustained yield principle in the Alaska Constitution. I appreciated the history lesson that spun out from it in their Opinion. For one thing, they pointed me to some of the framers’ thinking around the sustained yield principle at the Alaska Constitutional Convention of 1955-1956 (bolding is mine for emphasis):

As to forests, timber volume, rate of growth, and acreage of timber type can be determined with some degree of accuracy. For fish, for wildlife, and for some other replenishable resources such as huckleberries, as an example, it is difficult or even impossible to measure accurately the factors by which a calculated sustained yield could be determined. Yet the term "sustained yield principle" is used in connection with management of such resources. When so used it denotes conscious application insofar as practicable of principles of management intended to sustain the yield of the resource being managed.1

In the section that I bolded, the framers express a now-quaint perspective: it is impossible to derive such numbers (volume, growth-rate, etc) from wild nature. Now, 70 years later, and there is a great deal of feeling that we can indeed combine precedent, budget, a good spreadsheet, and a survey, and derive such numbers about most anything.

It’s easy to forget, and so I want to take this opportunity to remind readers that we got to here from there, and it was and is a process. The framers of Alaska’s constitution didn’t think we could figure out such numbers and now we mostly think we can, confident in our uncertainty as we are. That’s a lot of movement!

And with that I’ll delve into the early history of herring counting in Sitka.

***

In 1947, Lawrence N. Kolloen (as Aquatic Biologist for the Division of Fishery Biology) wrote USFW Fishery Leaflet 252: THE DECLINE AND REHABILITATION OF THE SOUTHEASTERN ALASKA HERRING FISHERY2, describing a corrective path from massive commercial catch and apparent decline through the 1930’s and the partial rebuilding that followed a year without fishing in 1940.

In the 1947 leaflet, Kolloen used what he knew from limited ground observation, interviews, and catch data, to sketch out his theoretical abundance of the Sitka herring population between 1929 and 1946. He conditioned it by saying: “The determination of the size of population by actual count, is in the case of fish, obviously impossible. It has been necessary, therefore, for fishery biologists to apply certain indirect methods in order to determine the relative change in size of population from year to year. The two measures commonly used are the total catch and the patch per unit of fishing effort.” Those aren’t reliable measures by any stretch and he knew it, but he found them satisfactory for the purposes of tracking relative abundance year over year.  I don’t think I’ve seen an earlier example of a herring population chart for any place, and in retrospect I think it’s sort of an interesting attempt:

The chart tells a story of a decline from 1929-1941, where the decline of older age classes of herring outpaced the rise of new successful age classes amid summertime fishing pressure off Cape Ommaney (south end of Baranof Island). At the time most herring fishing was for “reduction”, producing feed meal, fertilizer, and oil. In Kolloen’s telling, a fisheries closure combined with successful age classes in 4 of 6 years between 1939-1944, returning the fishery near to prior levels.

By straining the scarce data available to him through his scientifically trained self, he figured that maybe during that time period the Sitka herring population had ranged between 150,000,000 and 450,000,000 herring. Kolloen’s range in the hundreds of millions of herring - that many herring, if an average weight of 125g is assumed, would weigh in at between 20,668 - 62,005 US tons.

To put that into perspective, ADF&G has estimated more herring than the high end of Kolloen’s range in all but two years since 2008. Again, 406,228 tons of herring - more than 6 times Kolloen’s highest numerical imagining - are expected to spawn in Sitka Sound this spring.

And yet - surveys of subsistence users have indicated that subsistence needs were not being met due to poor access to herring eggs in most of the last 15 years. The only good explanation: Kolloen was operating from a place of imagination, and ADF&G operates from certitude, and the two exist on different scales.

Kolloen saw good herring years in Sitka and he saw years that he thought were bad (I’ll talk about one in a follow-up soon, but, spoiler: it really doesn’t sound that bad). My best guess from here is that he probably mis-imagined the vastness of the herring population by something like an order of magnitude. He may have more or less had a pulse on relative abundance between those years, there were always a whole lot more herring than he’d figured.

My point, again: enumerating herring ain’t easy. Kolloen was the first to try.

Best,

Peter

P.S : I’ve gotten a few questions and some day soon I’ll assemble a few and see if I can answer em. Ask ‘em if you’ve got ‘em!

P.P.S! : I’ll use the end of entries as a place to dump pdfs of things that I’ve dug up that I don’t think are otherwise available on the internet. For instance, below is Kolloen’s 1947 leaflet! I think I tracked it down at the National Archives in Seattle, WA.

1947 7 Kolloen Usfw The Decline And Rehabilitation Of Southeast Alaska Herring5.27MB ∙ PDF fileDownloadDownload