Figure 7. Cline analysis showing the fit of the best model based on the proportional assignment of populations to the Bruce spanworm genetic cluster (Q ) for each sampled year along the Massachusetts transect (top) and the geographic center ± 2LL as estimated in the R package ‘hzar’ (middle). The number of individuals collected at each trap averaged across the 2007-2018 sample years (bottom). Distances are presented in relationship to T00.