3.2 Seasonal activity of movements on the network

The average number of monthly movements was 26,212 (2017), 32,872 (2018), and 40,165 (2019). According to the Mann-Kendall seasonal test, the overall time series of the monthly number of movements increased over time (p<0.001). There was also a shift in the central trend, detected by a change point (k) (Pettit’s test), which corresponded to May 2018 (k=17, p<0.001) (Fig. 2A) (SI 2). The monthly average seasonal activity of the movements was highest from May to August and December and less frequent from January to April and from September to November (Fig. 2B).

Figure 2. Seasonal plots of movements in the Ecuadorian pig network. (A) Monthly number of movements in separate years, shift in central tendency (k). (B) Graph of the subseries as a separate mini time series; the blue line represents the mean of the observations within each season (month).