DOI: https://doi.org/10.3354/aei00181
copiedNearby farms are a source of lice for wild salmonids: a reply to Jansen et al. (2016)
ABSTRACT: Jansen et al. (2016; Aquacult Environ Interact 8:349-350) question the regression analysis presented in Serra-Llinares et al. (2014; Aquacult Environ Interact 5:1-16), which correlates lice abundances on farmed and wild fish. Jansen et al. (2016) argue that the correlation might not reflect a cause–effect relationship but be instead a mere artifact of the spatio-temporal covariance in lice abundance on farmed and wild fish driven by temperature. In this Reply Comment we revisit the analysis presented in Serra-Llinares et al. (2014) and further re-analyze our data following the statistical approach used by Helland et al. (2015; Aquacult Environ Interact 7:267-280), to rule out the potential confounding effect of temperature. We conclude that Jansen et al. (2016) were correct in conveying part of the observed correlation to the effect of temperature; however, there is solid evidence of a significant influence of lice originating from nearby farms on the observed lice abundances on wild fish, even after the effect of temperature is accounted for.
KEYWORDS
R. M. Serra-Llinares (Corresponding Author)
- Institute of Marine Research, PO Box 6404, 9294 Tromsø, Norway
P. A. Bjørn (Co-author)
- Institute of Marine Research, PO Box 6404, 9294 Tromsø, Norway
B. Finstad (Co-author)
- Norwegian Institute for Nature Research, PO Box 5685, 7485 Trondheim, Norway
R. Nilsen (Co-author)
- Institute of Marine Research, PO Box 6404, 9294 Tromsø, Norway
L. Asplin (Co-author)
- Institute of Marine Research, PO Box 6404, 9294 Tromsø, Norway
