Effective population size estimation
We used NeEstimator v.2 (Do et al. 2014) via the “dartR” wrapper to try to estimate the current effective sizes of the King Island and Tasmanian scrubtit populations, using the linkage disequilibrium method with no singleton alleles. We also estimated the effective size of (i) each a-priori scrubtit subpopulation based on sampling locations; and (ii) the ‘east coast’ and ‘rest of the mainland’ Tasmanian scrubtit populations. We used this approach based on the results of the population structure analysis and given the NeEstimator algorithm assumes random mating and non-overlapping generations (Do et al. 2014) which are both unlikely to be the case for scrubtits (see results).