Dynamics of reduced genetic diversity in increasingly fragmented populations of Florida scrub jays,Aphelocoma coerulescens

• DOI: 10.1111/eva.13421
• Publication Date: 2022-05-14T12:30:27Z
• Authors: Tram N. Nguyen; Nancy Chen; Elissa J. Cosgrove; Reed Bowman; John W. Fitzpatrick; Andrew G. Clark
• Keywords: Effective population size

Abstract Understanding the genomic consequences of population decline is important for predicting species' vulnerability to intensifying global change. Empirical information about changes in populations early stages decline, especially those still experiencing immigration, remains scarce. We used 7834 autosomal SNPs and demographic data 288 Florida scrub jays ( Aphelocoma coerulescens ; FSJ) sampled 2000 2008 compare levels genetic diversity, inbreeding, relatedness, lengths runs homozygosity (ROH) between two subpopulations within dispersal distance one another but have experienced contrasting trajectories. At Archbold Biological Station (ABS), FSJ has been stable because consistent habitat protection management, while at nearby Placid Lakes Estates (PLE), declined precipitously due suburban development. By onset our sampling 2000, birds PLE were already less heterozygous, more inbred, on average related than ABS. No significant occurred heterozygosity or inbreeding across 8‐year interval, relatedness among individuals decreased PLE, thus by did not differ sites. harbored a similar proportion short ROH greater long ABS, suggesting continuous shared history past, which now recent inbreeding. These results broadly uphold predictions simple models based inferred effective sizes rates immigration. Our study highlights how, just few generations, formerly can diverge with severe local despite ongoing gene flow.