I guess you missed this part.
From your link. "About this blog"
"We are unashamedly pro-aquaculture."
Just saying.lol
This is a prime example of what frustrates me when discussing aquaculture with many critics.
When an opponent makes a claim based on back-of-the-napkin calculations, completely lacking any scientific corroboration, that serves to support the anti view - it is given an immediate pass.
When someone in support of aquaculture makes a counter-claim using evidence or valid methodology it is dismissed - simply due to confirmation bias.
On the topic of sea lice in British Columbia, what models created by people like Krkosek fail to incorporate is the natural world - resulting in an over-simplified and unrealistic result.
You can calculate the amount of larval lice generated using averages of gravid females found in samples on the farm - what you can't realistically estimate is the survival and success of those lice in relation to their ability to attach to passing wild smolts.
(A mortality calculation is used, with no estimate of predation and infection ratio incorporated)
It has been shown in research from Washington State farms that the biomass of filter and detritus feeders on cage systems is significant, and that the variety of fish and other aquatic animals utilising the farms as habitat are also feeding on anything they find in or around the farms.
http://www.wfga.net/documents/marine_finfish_finalreport.pdfI've personally experienced huge schools of herring, anchovy, and pilchard feeding adjacent to farms.
It is partly because of these natural controls that we don't see lice generated by farmed hosts creating a reliable, measurable increase in infection rates on wild fish nearby.
Also, larval sea lice are zooplankton which wild smolts and other small fish feed on - there's a reason naturally occurring lice get close enough to infect stickleback and salmon in the nearshore environment.
There are also environmental aspects key to louse survival including temperature and salinity that have a major role in their abundance - some years are worse than others.
Simply put, if the models accurately portrayed unnatural, uncontrolled increases in louse abundance related to farmed salmon populations we would see a correlation in survival rates in wild populations adjacent to farming areas.
Not only has this not been seen, but research has shown (Morton's own paper) that there is no statistical difference in areas with and without farms.
"The survival of the pink salmon cohort was not statistically different from a reference region without salmon farms."
http://icesjms.oxfordjournals.org/content/early/2010/10/09/icesjms.fsq146.abstractWhat we have is researchers creating papers which hypothesise impacts that are not seen at the population level, and only seem to exist in either models or speculative findings.
If farms had an additional negative impact on wild populations it would show up in enumeration work being done all over the coast.
Since we don't see that, I am confident in my opinion that the effects of salmon aquaculture on wild populations are either neutral, or too small to be measured against the vast range of natural impacts.
But, then again, I am unashamedly pro-aquaculture, so...
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Topic: Get your facts straight? (Read 1688760 times)