The total number of farm-reports for each bath treatment category for the years 2013 and 2014.

<p>The number of different farms that reported bath treatments were 474 (mean = 2.02 and max = 7 treatments per farm) in 2013 and 470 (mean = 2.34 and max = 8 treatments per farm) in 2014.</p

Farms tested with bioassays in 2013 and 2014 (upper panel) and kernel densities of bath-treatments against salmon lice along the Norwegian coast in 2013 and 2014 (lower panel).

<p>The red line in the upper left panel shows the plot of the geoindex regression spline through farm latitudes and longitudes (see <i>2</i>.<i>1</i>.<i>2 Geoindex</i>).</p

The fixed effect of geoindex (± 95% CI) on the probability of female adult lice dying after exposure to Azamethiphos (concentration = high; year = 2013) in the bioassay tests, for mean values of the kernel density of treatments (KD 1; left panel).

<p>The right panel shows the relationship between geoindex and latitudes.</p

Parameter estimates and confidence intervals for the final mixed effects logistic model for lice-level mortality in bioassay tests.

<p>AIC in the full model was 17889.</p

Model predictions of the probability of adult female salmon lice being immobilized/dying when exposed to high concentration azamethiphos in bioassays, as a function of the kernel density of treatments (KD1) attributed to the test farms.

<p>The lines represent predictions using only fixed effects, whereas the points represent farm specific predictions when the random effects were accounted for. The upper lower panels represent predictions and farms sampled in 2013 and 2014, respectively. The geoindex scenarios represent predictions assuming farm locations at the 95% high percentile geoindex of 22.4 (High geoindex), the 5% low percentile geoindex of 0.4 (Low geoindex), or a geoindex of 10.3 (Intermediate geoindex). These geoindexes corresponded to lattitudes of 70.3, 64.6 and 59.6 decimal degrees north, respectively (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0149006#pone.0149006.g003" target="_blank">Fig 3</a>).</p

Maps showing farm specific predictions of the probability of adult female lice dying in high concentration azamethiphos bioassays, while accounting for the farm level random effects, in 2013 (left panel) and 2014 (right panel).

<p>The black symbols with latitude labels refer to the three modelled scenarios for the geoindex, as shown in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0149006#pone.0149006.g002" target="_blank">Fig 2</a>.</p

The number of farms tested with bioassays, the number of salmon lice (npar) and the range of salmon lice per farm (f^-1) exposed to the antiparasitics.

<p>The number of farms tested with bioassays, the number of salmon lice (npar) and the range of salmon lice per farm (f^-1) exposed to the antiparasitics.</p

Descriptive statistics for the variables predicting the binomial outcome: dead or live salmon lice in bioassays with exposure to azamethiphos or deltamethrin.

<p>ΔAIC represents the difference in AIC values when omitting the given variable from the final regression model (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0149006#pone.0149006.t004" target="_blank">Table 4</a>) with an AIC of 17889 (not given for Farm bath-treatments since this was not part of the final model).</p