University of Kent

Dr Jim Groombridge's research

Searching for evidence of a historical population bottleneck in the Seychelles kestrel: microsatellite genotyping of 100-140-year-old museum specimens.

A Royal Society Research Grant

The Mauritius kestrel is believed to have experienced a population bottleneck of a single pair in 1974. My previous genetic work (Groombridge et al. Nature 2000) showed current microsatellite diversity in this species to be low, compared to unusually high ancestral levels sampled from pre-bottleneck museum skins. A broader survey of current diversity in other kestrels showed the Seychelles kestrel population to be similarly impoverished, but historical records suggest that this species did not undergo a bottleneck of similar severity.

The Seychelles population did not require intensive recovery, and today persists in high numbers. This scenario presents an opportunity to investigate the genetic effects of historical population bottlenecks for island endemics: both kestrel species have similarly low genetic diversity today, but differ in their histories of population size. Geographically, Mauritius is a single large island, whereas the Seychelles archipelago is made up of many smaller islands, which comprised the ancestral range of the Seychelles kestrel. In addition, our knowledge of the evolutionary history of kestrel colonisation across the Indian Ocean islands is based upon a molecular phylogeny (Groombridge et al. Mol. Phylog. Evol. 2002).

This current research project at the University of Kent involves the use of microsatellite markers to genotype DNA extracted from sampled museum specimens, and to compare those levels of genetic diversity to that retained by the current population on the Seychelles. The genetic work is being carried out partly at DICE, University of Kent, and partly at the NERC Sheffield Molecular Genetics Facility, University of Sheffield. Museum collections throughout the UK, Europe, and elsewhere are being used.

Publications

Groombridge, JJ, Dawson, DA, Burke, T, Prys-Jones, R, Brooke, M de L, and Shah, N (2009). Evaluating the demographic history of the Seychelles kestrel (Falco araea): genetic evidence for recovery from a population bottleneck following minimal conservation management. Biological Conservation 142, 2250-2257.