Theodore Squires

and 3 more

Using whole genome re-sequencing data we study population level associations with regional climate data and predict the response to future climate change in populations of cold-adapted grouse species from the Holarctic: rock ptarmigan (Lagopus muta), willow ptarmigan (L. lagopus), and red grouse (L. scotica). We infer the relationships among multiple regional populations of these species and examine their individual adaptations to environmental factors, genetic offset (gap) in the face of expected environmental change, and predict genes that may be associated with climate risk. Genomic vulnerability to future climate change scenarios (also known as offset or genetic gap) is predicted for each of the populations in the context of predicted range contractions under various global development scenarios. We show that different regional populations have SNP distributions implying differentiated influences of climatic parameters on predicted population-level persistence. We find evidence of adaptation in all species towards local annual temperature ranges and precipitation regimes. Ancestry proportions derived from principal components analysis identified genetic similarities between east and west Greenlandic populations of rock Ptarmigan, all Scandinavian willow Ptarmigan, and red grouse in England and Ireland. Based on our evidence of local adaptation, genetic association with these climatic variables, and expected environmental changes across the north Atlantic and Arctic, we suggest that general warming and increased rainfall will be driving pressures on these species with more stochastic weather patterns adding to threats against more geographically isolated groups with greater risks at higher latitudes.