The North Island Gazette published a recent letter to the editor written by Cory Percevault, titled, “Press release spins sea lice study”, February 22, 2011. Here are Mr. Percevault’s 3 concerns about supposed discrepancies between our press release and the peer-reviewed study it refers to, and our response:
1. “The press release states that sea lice from salmon farms have been fingered in Fraser Sockeye die-off”.
No, our release stated, “The implications of these infections are not fully clear, but in addition to any direct physical and behavioural impacts on juvenile sockeye, sea lice may also serve as vectors of disease or indicators of other farm-origin pathogens”.
2. “The press release says environmental conditions may have been partly responsible for the difference (in sea lice levels at the North coast), but concluded that neither temperature or salinity differences could explain the much lower incidence of sea lice infections.”
Mr. Percevault failed to mention that our press release and published article both stated the above, and that the paper also provided robust statistical evidence to demonstrate that the overall effect of salinity could not explain the elevated levels of sea lice on wild salmon after exposure to fish farms.
3. When describing the high numbers of lice found on juvenile Fraser sockeye near a processing plant, Mr. Percevault suggests that, “this anomaly was apparently inconsistent with the model assumptions – and resulted in the data being thrown out. Yes, it’s a bummer when data doesn’t match your assumptions.”
No, as our paper states, when we included this site in our formal statistical tests, the primary conclusions remained the same (i.e., salmon farms are the most probable source for sea lice infecting juvenile sockeye from the Fraser River regardless of whether this site is included or excluded).
I am pleased Mr. Percevault believes our study is a very important part of the discussion to reduce industrial practices that harm our environment. However, inaccurate claims and omission of facts about our science only serve to prolong public confusion. I encourage everyone to consult our published paper by Googling “PLoS One sea lice”.