Fig. 3

Smooth covariate functions explaining nightly abundance of Cx. pipiens (a) and Cx. tarsalis (b). Smooth functions from final generalized additive models are shown for the spatio-temporal surface (top), seasonality in a fully urban area, seasonality in a fully crop area, seasonality in a fully natural area, deviation (°C) from the 30-year monthly average temperature on the night of trapping and the average temperature (°C) during the 2 weeks prior to trapping (bottom). The shaded region represents the 95% confidence interval for one-dimensional functions. A representative slice of the three-dimensional spatio-temporal surface is presented for 2011 at the midpoint of the typical WNV season (week of 1 August). Spatio-temporal surfaces are plotted on individual axes for each species to resolve the spatial scale