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[jon5hill]

http://www.bbc.co.uk/news/uk-scotland-highlands-islands-20236291

[Dave]

Thanks Jon, I was wondering where Krkosek wound up.   Wasn't it him and Ms. Morton who predicted sea lice would cause the extirpation of Broughton pinks?

[StillAqua]

Interesting study Jon. The original paper is here:
http://rspb.royalsocietypublishing.org/content/early/2012/11/01/rspb.2012.2359.full.pdf

[jon5hill]

Pinks returned in abysmal numbers in the proximate years that were covered by Krkoseks model. The existing farming conditions changed dramatically after that. Closures, an entire fallow year, and rigorous slice application before juvenile outmigration changed the landscape. There is great uncertainty associated with models especially in the context of trying to use them to make long term predictions. All models break down in time, as the only constant thing about our universe is change itself.

[Dave]

There is great uncertainty associated with models especially in the context of trying to use them to make long term predictions. All models break down in time, as the only constant thing about our universe is change itself.

Exactly.  That's why some question the wisdom of Krkosek and Morton's comments as that's when they and the movement to remove salmon farms from BC  lost considerable credibility, imo.
Apologies for derailing, a bit, your post regarding Scottish sea lice issues.

[alwaysfishn]

The fact that feedlots changed the way they treated sea lice after some of those studies came out, in itself shows the benefit of what folks like Morton and Krkosek have done. The shameful part about this is that industry and government should be the lead in these sort of issues, not followers.... 

The feedlot industry reminds me of the kid in class with an inferiority complex.....  to make up for it he criticizes everything everyone else in class says, thinking it makes him look smarter. Unfortunately everybody ends up hating him.

[curious]

Yes, thank you, interesting study as well as Dr. Krkosek's and his associates funding sources.
 "This work was supported by funding from the University of Otago, the Norwegian Directorate for Nature Management, the Canada Research Chair Programme at UPEI, the Norwegian Institute of Marine Research and EU Framework 5."

[shuswapsteve]

Thanks for mentioning that, Dave.  If we are going to talk about “abysmal” returns that followed 2002 we also need to consider the odd and even life history of Pink Salmon when making comparisons.  In the case of Mainland Inlet Pink stocks the even year appears to be the dominant.  Secondly, while I agree that an effort was made to minimize the sea lice levels (Broughton Sea Lice Monitoring Plan 2003) following 2002, if we are going to talk about what happened after 2002, we also need to look at the long term Pink escapement in the Broughton area.  The fact is that they have fluctuated with some big years and some years with some very poor returns – even before salmon farming.  Thirdly, if we are going to talk about what happened during and after 2002, we also need to consider that the farm source sea lice was actually greater during the 2000 pink salmon outmigration which came back as a record return just a year prior to the collapse in 2002.  Lastly, Pink Salmon are actually increasing in abundance in the North Pacific.  The potential for competition with Sockeye was mentioned in the Final Report.

Krkosek et al 2007 used too small of a time range which ultimately didn’t show what was actually happening.  How can you take a snap shot over a short period of time and predict local extinction?  During the inquiry, Josh Korman even alluded to the low statistical power in the fish health data because it is only available from 2003 to 2010.  Ultimately, longer term data sets are going to be needed and this is what Cohen put in his recommendations.  This seems to be a common theme for most of the 75 recommendations.  In Cohen’s Final Report, the consensus was that sea lice did not act alone to cause the decline of Fraser Sockeye; however, Cohen believes that sea lice could have acted in combination with other stressors to contribute to the decline.  The debate has been how much – some say it is low while others say it is much more than that.  When reading Cohen’s findings, it seems that governmental and non-governmental biologists seem to agree on what research is required from this point forward (for the most part anyway).