upper Fraser River sockeye 2011: DFO Recipe for Extinction

adapted from Cohen Commission tech report #2

It might be with some irony that today the Cohen Commission into declines of Fraser River sockeye is conducting hearings into fisheries Monitoring and Enforcement. There is probably little question that better Monitoring and Enforcement could assist Fraser sockeye stocks; however, on a cost-benefit analysis between ‘good management‘ vs. ‘monitoring, enforcement, & compliance‘ would there really be much comparison…?

Let’s look at this coming year’s sockeye forecasting and pre-season planning (2011): As the Recipe for Upper Fraser Sockeye extinction is plain as day

Below is a rather complex chart produced by the Department of Fisheries and Oceans that documents the “recent productivity” of 19 (of the over 150) distinct Fraser sockeye stocks.

The 19 sockeye stocks in which DFO actually has enough information to utilize are further grouped into four run-timing groups (Early Stuart, Early Summer, Summer, and Late Summer).

These can be seen down the far left hand side — Column A. (I will break this chart down further with specific focus on some key numbers and columns).

 

DFO 2011 "Recent Productivity" Fraser Sockeye Forecast

First off, the Early Stuarts, one of the furthest upstream migrating Fraser sockeye — Northwest of Prince George in the upper Nechako drainage (Stuart River is main tributary — see map above), is in deep trouble.

In essence, what column “I” suggests is that the historical ‘mean run size’ for the Early Stuarts — based on all cycles — is 311,000.

On the 2011 cycle (Fraser sockeye predominantly run in four-year cycles) the mean run size is 172,000.

Columns “K” to “O” give the ‘probability’ of various forecasts.

Column K is the “10p” forecast suggesting that there is a 10% chance (or 1 in 10 chance) that runs will be at or below this number — for Early Stuarts that’s 6,000.

The standard generally used in pre-season forecasting is the 50p or 50% probability forecast which for Early Stuarts is 17,000 (column “M”).

So the Early Stuart median for all cycles is 311,000 — for the 2011 cycle-year it is 172,000 — however for this year the 50% probability pre-season forecast for 2011 predicts a run size of only: 17,000.

Even the best-case scenario (90p — 90%) predicts a run-size of only: 42,000.

(Note: Last year 2010 — the apparent big record year — the Early Stuarts met the 90p pre-season forecast and had an estimated return of 100,000).

However, raise any questions on the Early Stuart sockeye and DFO will say “but we’ve been in conservation mode on these fish for decades”. Yet, even just as far back as 1997 — the total run size of the Early Stuarts was estimated at almost: 1.7 million sockeye.

And yet that year the estimated catch was over 770,000.

Worse yet, an en-route loss is estimated at over 630,000.

Only an estimated 260,000 reached the spawning grounds. A mere 15% of the total run.

And then this year the best case scenario suggests only 42,000 as a total run size, not even what might reach the spawning grounds — some 1000+ km upstream…

Hmmm. wonder why we there’s a problem…?

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Estimated Returns and Historical Productivity

So, yes, the Early Stuarts have been in trouble for quite some time — however, it seems like this is akin to a flu-bug in the upper watershed. Trouble for upper Fraser sockeye seems to be contagious..

In the “Early Summer” grouping there are two sockeye stocks with enough information for “management” purposes — the Bowron (returns to Bowron River east of Prince George, and northeast of Quesnel) and the Nadina (returns to upper Nechako River, west of Prince George and southwest of Fraser Lake).

Here are the numbers blown up from the above chart:

2011 Fraser sockeye forecast: Bowron and Nadina River runs.

This half of the chart shows the estimated Effective Female Spawners (EFS) in columns “C” and “D”.

The “BY” stands for Brood Year. Therefore, 2007 is the Brood Year (BY) for the majority of returns this year: 2011 — as sockeye largely have a four-year life cycle. However, some years and some runs have more five-year old sockeye return as well. Often this is in the range of approximately 20-30% of the total run. And thus column “D” is the estimated Effective Female Spawners of 2006.

And so in 2007, the estimate suggests there were 1,100 Effective Female Spawners (EFS) and in 2006 there were 600 for the Bowron.

For the Nadina there were an estimated 1,000 Effective Female Spawners in 2007 (the main brood year for this year’s 2011 returns) and 4,500 EFS in 2006.

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The next columns — “E” and “F” are estimates of the productivity of each Effective Female Spawner over an 8-year time period (column E) and 4-year time period (column F).

For a population of any critter each female (effective female spawner) must average a productivity of 2 progeny that live to become reproductive adults — ideally an average of one male and one female — just to maintain any population with no growth or depletion.

The Bowron has an estimated productivity of 2.4 (over 8 years) and 2.1 (over 4 years) returning adults for each female spawner (the numbers in red boxes — red meaning bad/stop ).

estimated productivity of Bowron sockeye stocks

This means that the Bowron stock of Fraser sockeye is barely replacing itself at current productivity.

The Nadina is faring a little better with estimated productivity over 8 years of 3.0 (in the red box) and over 4 years of 4.6 returning adults per effective female spawner (in the yellow box — meaning, caution).

estimated productivity of Nadina sockeye

Sockeye salmon enhancement facility, Nadina River, British Columbia

 

(It should be noted that the Nadina sockeye largely utilize man-made spawning channels… and they are still in trouble…).

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The next set of numbers further along the right on the chart are rather revealing as well, here’s a clip with columns C-H taken out:

 

Fraser sockeye forecast_2011 Estimated probabilities for Bowron & Nadina stocks

Columns “I” and “J” are showing average “mean” runs sizes for these various runs as an overall average of all years previous — “all cycles” column “I” and the four-year cycle that includes 2011 column “J”.

For the two runs of concern — Bowron and Nadina — one can quickly see that the difference between the average run sizes and the various probabilities of run sizes this year — there’s a big discrepancy.

(And it must be pointed out that this is estimates of Total Run Size returning to the Fraser which may be targeted for fisheries — not the total run size that is predicted to reach, or reached, the spawning grounds.)

As mentioned earlier the 50p or 50% probability forecast is the one most commonly used during pre-season forecasts. For the Bowron that’s 5,000 estimated as a total run size (as compared to a mean average of all years of 39,000) and for the Nadina 12,000 (as compared to a mean run size of 80,000). (Remember, total run size predicted, not what’s estimated to reach the spawning grounds).

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Recipe for Extinction

The Bowron and Nadina River adult sockeye stocks migrate into the Fraser River approximately the same time as several other stocks that migrate to different parts of the Fraser River. The other stocks are listed in the chart above — names like Fennell, Gates, Pitt, Raft, etc. These stocks are spread from the upper, upper Fraser through the upper Thompson River, right down to the lower Fraser with the Pitt.

All, most likely, quite genetically distinct from each other — however, simply grouped because of run-timing. These are called the Early Summers for exactly that reason. Convenient for fishing plans… maybe not so convenient for conserving genetic diversity of stocks… or even conserving stocks themselves…

If you look through the various other runs within the Early Summers grouping, a few are looking relatively healthy, with 50% forecasts suggesting run sizes a little larger then the mean averages. There is even some green in the productivity and EFS boxes.

Total 50% probability pre-season forecast for all Early Summers is 453,000. With a few healthy runs… this means potential fisheries targeting this Group.

At the present time apparently DFO and Pacific Salmon Commission is considering fishing plans that would target a 40% exploitation rate on these Early Summers — which suggests that close to 200,000 of these Early Summers could potentially be targeted in fisheries.

For the Bowron and Nadina sockeye runs, this could mean total disaster.

There are only a total of 17,000 total fish at the 50% probability pre-season forecast for both these runs combined — and this is just fish forecast to reach the Fraser River, not the actual number forecast to reach the spawning grounds, which for these two runs is over 1000 km up the Fraser River.

These 17,000 potential fish could easily be swallowed in fisheries targeting other healthier Early Summer stocks.

Or, let’s say even conservatively that these targeted fisheries only catch half of the Bowron and Nadina returning runs — 8500. Conservative estimates suggest that 40% or more of these fish will die en route or prior to spawning. If that occurred there would still be 90% of the total run wiped out.

This is all considering fish on paper… which is the problem here.

The Recipe of Extinction for upper Fraser sockeye stocks is: mixed stock fisheries based on fisheries management plans that manage to the Aggregate Groups (only four) and do not discern between endangered individual, genetically distinct runs — such as the Bowron and Nadina stocks.

(let alone the 130 or so unnamed Fraser sockeye stocks that don’t have enough information to be considered by DFO or the Pacific Salmon Commission).

Tomorrow?

We consider the Late Stuarts and Stellako, two more Upper, Upper Fraser River sockeye runs that face a worse scenario as part of the Summers group of Fraser sockeye.

They are the Recipe for Extinction — Chapter 3.

6 thoughts on “upper Fraser River sockeye 2011: DFO Recipe for Extinction

  1. Dave

    The stock groupings identified in the forecast encompass more than 17 of the 130 stocks. The Early Stuart stock grouping alone contains over 30 individual stocks. Those 17 stock groups listed actually include pretty much every sockeye stock in the Fraser.

    As for this year’s forecast and fishing plans, we are coming off of a disastrous brood year escapement watershed-wide. Couple that with lower that average productivity over the past few cycles, and it does indeed spell the potential for very poor returns to upper river stocks. Fortunately (well, sort of) for those upper river stocks, the lower river stocks didn’t fare much better 4 years ago. Since the Early Summer groupd is managed as an aggregate (with some exceptions, which I will touch on below), the overall run size may not be adequate to allow the 40% exploitation rate that you mention. This decision would be based on a pre-season set of decision rules (Total Allowable Mortality, or TAM rules) that identify acceptable levels of exploitation at different run sizes. Typically, the run size has to reach a certain threshold for there to be any TAC (Total Allowable Catch). Without high abundance of co-migrating stocks, there shouldn’t be much (if any) TAC available. for Early Summers.

    As an aside, last year the Early Stuart fishing closure was extended by one week to protect the earliest migrating component of the Early Summers, of which Bowron and Nadina (and Taseko, an Early Summer stock in greater danger) belong to. Hopefully this will continue this year.

    It is likely that any TAC available on Early Summers may be used during targetted fisheries on co-migrating Summer run sockeye, whose migration timing overlaps with later-migrating Earlys (Scotch/Seymour primarily). Hopefully the Panel remembers the lessons learned from 2004 (which they don’t always. There are always folks on it just itching to fish at the slightest indication of increased run size), but there may be a strong push to fish the summers if they return in any strength (which would basically be the Chilkos alone. The others would get swept up along the way).

  2. john goodenbad

    Wow.. Here I was thinkin Fraser river runs were comin back..l..I worked for BC Pckers between 1981 1990.. Collectin fish in from Gillneters and we’d run em back to the cannery in Steveston.. Back then . the best run we had The Gill Netters were pullin in about 2000 sockeye a set. A fabulous run.. There was a 24 opening for commercial fishing..They extended another 24 hrs..Then another 12.,, that was longest they’ve aloud continuous fishing. 60 hrs of hundreds of gill netters .. BC Packers processed 100,000 lbs a day for 5 days.. They were full Didn’t want more sockeye.. That killed .. Fraser river sockeye. Same story as what your sayin….THE DOF OBVIOUSLY CANT COUNT. — 21 years later I’m reading this ..nothing changed. With proper fish management.. The Fraser river could thrive again

  3. salmon guy Post author

    thanks a lot for the comment Dave. And, yes, hopefully the Fraser Panel of the Pacific Salmon Commission knows their history lessons…

  4. salmon guy Post author

    thanks John, even sadder is the number of people such as yourself that state such similar sentiments… eg. “20 years later and nothing has changed…”

    Within DFO… many of the same folks doing the “management” side of things…

  5. Dave

    When it comes to Fraser sockeye, it isn’t exactly DFO that manages the fishery, but the Fraser River Panel of the PSC. The DFO staff that are on the Technical Committee of this panel are actually mostly younger staff that have not been around for the past 25 years, and actually bring a fresh approach to the issues. The Panel itself though has several old-timers representing industry, First Nations etc that have been around for a while.

  6. salmon guy Post author

    yes, duly noted. thanks Dave.
    And yes, certainly some faces that have been around for quite some time on all sides.

    the old Einstein saying, and i’m paraphrasing, “insanity is defined as doing the same thing over and over and expecting a different result…”

    not to say that some decent work isn’t done at those levels, it might just be time for a serious audit of practices and assumptions and approaches…?
    is that the Cohen Commission… hmmm… yet to be determined… many might suggest… ????

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