[env-trinity] Iron Gate: If the dam is removed, the fish hatchery would b...

FISH1IFR at aol.com FISH1IFR at aol.com
Thu Feb 16 17:45:33 PST 2012


In a message dated 2/16/2012 5:24:33 P.M. Pacific Standard Time,  
t.schlosser at msaj.com writes:

The Biological Assessment on the Preferred Action of Interior's EIS on  
Klamath points out that total chinook returns to the river will decline  
substantially after PacifiCorp stops replacing the IGH output. See e.g., pages  
214-15 of _this._ 
(http://klamathrestoration.gov/sites/klamathrestoration.gov/files/Klamath%20BA_%20Final%20_10-03-11.pdf)   

PacifiCorp is obligated to replace IGH chinook output for 8 years  after 
removal of IGD but no party has agreed to fund or provide replacement  
production after that.

_http://www.heraldandnews.com/news/article_cdf4af6e-586b-11e1-8b2e-0019bb296
3f4.html_ 
(http://www.heraldandnews.com/news/article_cdf4af6e-586b-11e1-8b2e-0019bb2963f4.html) 
Colleagues...
 
The Biological Assessment appears to be incorrect on  this point.  The 
projected increase in chinook runs size after dam removal  and KBRA benefits is 
not "hatchery dependent" because it was assumed that, after  stabilizing 
reintroduced populations, that Iron Gate Hatchery would close.   Here is my 
reply to Tom Schlosser noting this problem from another  forum:
 
 
 *******
 
Interesting, but [your assumption that fish numbers would decline after dam 
 removal] is based on some false reasoning. 
 
You should be aware that the DEIS Salmon Production Model was run with  the 
assumption of NO Iron Gate Hatchery production at all, to be  
conservative... and still comes up with the 83% production increase you cite, at  least 
for fall chinook. The note [above] is not in fact based on that fact,  so you 
are assuming a double subtraction that cannot mathematically be  made. 
 

In addition, hatchery fish have notoriously lower survival rates in the  
natural environment than wild fish as they have become "hatchery dependent" 
even  on the genetic level. There have been (literally) hundreds of studies 
verifying  this phenomenon, and the Klamath Iron Gate Hatchery is no 
exception. Genetic  drift to make a fish more genetically fitted to hatchery life, 
but less fitted  to life in the wild, has been demonstrated to occur (at least 
with steelhead,  but no reason to think it is not broadly applicable to 
their cousins) within  just one or two generations!
 

In addition, hatchery fish are typically released at sizes larger than  
native wild fish (since they are well fed their whole lives in the tanks), and  
so predate on the wild smolt stocks -- hence, any introduced hatchery  
stocks can in fact REDUCE productivity of the wild stocks, resulting in a  
partial cancellation of any additional hatchery benefits in terms of sheer  
escapement numbers. In some studies, such as in the Alsea River, the more  
hatchery fish were introduced the LESS the ultimate adult escapement from that  
brood year -- in other words, there was a negative correlation! This is  
apparently because the larger hatchery juveniles simply ate up many of the wild  
juveniles in the short-term, but themselves had much lower overall survival  
rates over their entire lifecycle in the long-term -- so more of them just 
flat  out died in the ocean and from larger predators than would have 
occurred had  there been no hatchery "supplementation" to begin with.
 

You can check with the authors of the Chinook Production Model for  
verification of how the modeling was done, i.e., without assuming any hatchery  
production as a conservative assumption. As to the other flaws in assuming that 
 hatchery supplementation can replace a healthy wild stock with impunity, 
there  are literally hundreds of such studies in the literature that any 
salmon  biologist would help you locate, though it would take some legwork.
 

As is usually the case with biology, its all a LOT more complex than at  
first cut. But by and large, your juxtaposition of the two statements below 
and  your conclusion from that that the end result of dam removal will be 
FEWER  salmon in the river because of the loss of IGH production is simply not 
true so  far as I am aware of the science and modeling done. 
 


PS: The adult hatchery fish returns to the Iron Gate Hatchery in 2009, I am 
 told, was 12,263 adult chinook. This is far below the 53,400 number as 
estimated  IGH returns on which the note below was based. If, then, the dam 
removal and  re-established above-dams fall chinook runs had instead been in 
place that year  (for comparison), an estimated 41,000 would have been coming 
in with an IGH loss  of only 12,263 -- a net GAIN of over 28,700 adult 
spawners! This is of course  also simplistically assuming a one-to-one 
replacement, without any negative  hatchery-wild interactions. So you see, it all 
depends on how and what you  count, what your baselines are, and what data-years 
you are averaging from --  and what hatchery-wild interactions you count 
and how you count them, or  simply ignore. 
 

Hatchery programs also are expensive (and subject increasing to state  
budget cuts) and sometimes just flat out fail, from disease or human error. So  
relying on hatchery production always carries its own risks. These too have 
to  be considered.
 

-- Glen Spain
 
And in a later email exchange in which Tom asked for  some citations to the 
fact that the Chinook Model was run without reference to  any hatchery 
impacts, I responded as follows:
 
   
In a message dated 2/9/2012 9:05:00 A.M. Pacific Standard  Time, 
t.schlosser at msaj.com writes:

I agree  with many of your generalizations about hatcheries. Can you point 
me to where  it is made clear that the DEIS modeling assumes no IGH  
production.
Tom... Surely.... One can start here:
 


"Anticipated removal of the dams, combined with restoration of  aquatic 
habitats as anticipated in the KBRA, is predicted to increase the median  
annual production of adult Chinook salmon, in the absence of hatcheries,  by an 
average of 83 percent for the years after dam removal (see Figure 4.1-25).  
The Chinook salmon ocean commercial and sport harvests are forecasted to  
increase by an average of 50 percent, the inriver tribal harvest would increase 
 by an average of 59 percent, and the in-river recreational fishery would  
increase by an average of 9 percent in those years following dam removal 
(2021  to 2061)." SDOR pg. 86 of text (emphasis on key phrase added)
 



Then looking to the Source Document, which is:
 

Forecasting the response of Klamath Basin Chinook  populations to
dam removal and restoration of anadromy versus no  action
---- Noble Hendrix (2011)
 

"ABSTRACT: Two alternative actions are being evaluated in the  Klamath 
Basin: 1) a No Action Alternative (NAA) and 2) removal of four mainstem  dams 
(Iron Gate, Copco I, Copco II, and J.C. Boyle) and initiation of habitat  
restoration in the Klamath Basin under a Dam Removal Alternative (DRA). The  
decision process regarding which action to implement requires annual forecasts  
of abundance with uncertainty under each of the two alternatives from 2012 
to  2061. I forecasted escapement for both alternatives by constructing a 
life-cycle  model (Evaluation of Dam Removal and Restoration of Anadromy, 
EDRRA) composed  of: 1) a stock recruitment relationship between spawners and 
age 3 in the ocean,  which is when they are vulnerable to the fishery, and 2) 
a fishery model that  calculates harvest, maturation, and escapement. To 
develop stage 1 of the model  under NAA, I estimated the historical stock 
recruitment relationship in the  Klamath River below Iron Gate Dam in a Bayesian 
framework. To develop stage 1 of  the model under DRA, I used the predictive 
spawner recruitment relationships in  Liermann et al. (2010) to forecast 
recruitment to age 3 from tributaries to  Upper Klamath Lake, which is the 
site of active reintroduction of anadromy. I  also modified the spawner recruit 
relationship under DRA to include additional  spawning capacity between 
Iron Gate Dam and Keno Dam. In order to facilitate the  comparison of the two 
alternatives, I used paired Monte Carlo simulations to  forecast the levels 
of escapement and harvest under NAA and DRA. Median  escapements and harvest 
were higher in DRA relative to NAA with a high degree of  overlap in 95% 
confidence intervals due to uncertainty in stock-recruitment  dynamics. Still, 
there was a 0.75 probability of higher annual escapement and a  0.7 
probability of higher annual harvest by performing DRA relative to NAA,  despite 
uncertainty in the abundance forecasts. The median increase in  escapement in 
the absence of fishing was 81.4% (95% symmetric probability  interval 
[95%CrI]: -59.9%, 881.4%), the median increase in ocean harvest was  46.5% (95%CrI: 
-68.7, 1495.2%), and the median increase in tribal harvest was  54.8% 
(95%CrI: -71.0%, 1841.0%) by performing DRA relative to NAA (estimates  provided 
for model runs after 2033 when portion of the population in the  tributaries 
to UKL are assumed to be established and Iron Gate Hatchery  production has 
ceased)." (emphasis added)
 


And to get even deeper into the methodology of the Chinook  abundance model:
 


"I also calculated the percentage increase in abundance for  each paired 
iteration as (DRA – NAA)/NAA * 100%, which provided a quantitative  estimate 
of the difference in abundance. There were three periods that could  have 
different relative levels of abundance under DRA versus NAA: the period  
between model initiation and dam removal (2012- 2020); the period after dam  
removal but with active reintroduction in the tributaries to UKL (2021-2032);  
and the final period when the population in the tributaries to UKL are assumed 
 to be established and Iron Gate Hatchery production has ceased 
(2032-2061).  (Hendrix, (2011), pg. 17 -- emphasis added)
 


I will spare you all the equations.... I  can digest Bayesian functions but 
they do give me indigestion  unless I follow them with a quick glass of 
wine (grinning). But from the above  it is pretty clear that the Chinook 
production estimate modeling for the DRA  scenario was all done without reference 
to any IGH fish as a potentially  confusing factor in the final time frames, 
i.e., after dam removal.


=============================================
Glen H. Spain, NW  Regional Director
Pacific Coast Federation of Fishermen's Associations  (PCFFA)
PO Box 11170, Eugene, OR 97440-3370
O:(541)689-2000 --  Fax:(541)689-2500
Email: fish1ifr at aol.com
Home Page: _www.pcffa.org_ (http://www.pcffa.org/)   








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