Firstly - we should never wait until we have absolute proof in order to act in a timely fashion. We already discussed this earlier on this thread.quote:Originally posted by sockeyefry
Correct me if I am wrong, but I believe that article refers to preliminary data from a study in progress, and you should know the dangers of drawing conclusions before the completion of any study.
Secondly - the DNA results and the sea lice infestation numbers are NOT "preliminary" - it's what they got for this year and last.
Firstly - we all know that since there is repeated transfer between wild and cultured stock - DNA cannot be used to tell where the sea lice came from.quote:Originally posted by sockeyefry
Did they determine if the lice loadings were from farms and did they kill the fish? Just because a fish has lice doesn't mean thay are going to be harmed by them.
Secondly - we cannot use site-by-site farm-source sea lice loading as a point source because the numbers are unavailable because the government is protecting the farms from that kind of investigation. We already talked about this earlier, too.
So, NO - we currently have no method I know of to tell the source of any individual sea louse on any wild smolt.
However, we can look at modeling and other jurisdictions' experiences - all of which demonstrate the risk of transfer and population-level impacts are real and probable. Some authors have even quantified this risk.
Please don't insult all our intelligences by trying to claim that doesn't happen
Yes and NO - the harm is dependent upon both the numbers and stages of lice (e.g. motile or subadult lice are much more lethal to their host) - as well as the size (read weight) of the host fish.quote:Originally posted by sockeyefry
Just because a fish has lice doesn't mean thay are going to be harmed by them.
These levels of either sublethal or lethal harm have been quantified for some species - but are being debated between the 2 camps.
Generally something like more then 1 louse per gram of weight will kill a fish - while lesser levels can cause sublethal effects, including population-level increases in mortality. Please review earlier postings on this, and my last posting on how inadequate the trigger levels were (03/19/2009 : 10:53:15).
Yea - why not?quote:Originally posted by sockeyefry
You cannot compare the Frasr which flows through the most heavily populated area in BC, and therewfore receiver of the most human impact, with the Skeena. Besides which there are years when the Skeena Sockeye experience low poulation levels.
And yes - some years both rivers show similar results with changes in numbers - but have been mostly out of synch - with the Fraser most often severly impacted.
You wish to somehow repudiate the comment: "It's likely that many juvenile sockeye from the Fraser get killed when they pass-by the Broughtons and get loaded by sea lice from the fish farms."
You think that's an illogical or improbable suggestion? Why?
quote:Originally posted by sockeyefry
I also cite the population fluctuations of pink salmon in thwe Broughton before salmon farming began, during which time frame the lowest runs on record occurred, and the greatest runs occurred during the period in which farms were present in the Broughton. Based on this data how come no one has drawn the conclusion that the farms were good for the pinks?
Wow, sockeyefry. You do have a sense of humour, even.