Figure 3: Sensitivity analysis against assortativity, average migration rate, and population distribution. The local reproduction numbers in each geographical area are compared. (a) The local reproduction numbers for different assortativity: 0.7 (low), 0.8 (baseline), and 0.9 (high); (b) average migration rate: 25% (low), 50% (baseline), and 100% (high) of the maximum mobility (i.e., all birds migrate around the three areas annually); (c) population distribution: high-latitude:mid-latitude:Oceania = 1:1:1, 2:1:1, 1:2:1, and 1:1:2.