Avian populations are predicted to exhibit minimal genetic differentiation as a result of their high mobility, although some habitat specialists show fine-scale genetic structure.
To explore the relationship between habitat specialization and gene flow, researchers investigated the genetic structure of a saltmarsh specialist with high potential mobility – the clapper rail – across fragmented habitat along the Atlantic coast of North America. In examining genetics of nearly 150 clapper rails, they found moderate genetic diversity, no evidence of bottlenecks, and a weak pattern of genetic differentiation that increased with geographic distance. Authors concluded that the high gene flow connecting populations of this habitat specialist may result from ecological and behavioral factors that promote dispersal. As threats to saltmarsh habitats expand, the genetic diversity and population connectivity of clapper rails may promote resilience of their populations. Findings can inform potential fates of other similarly behaving saltmarsh specialists on the Atlantic coast.
Coster, S.S., Welsh, A.B., Costanzo, G.R., Harding, S.R., Anderson, J.T., Katzner, T.E., 2018, Gene flow connects coastal populations of a habitat specialist, the Clapper Rail (Rallus crepitans): Ibis, https://doi.org/10.1111/ibi.12599.