Anna Lisa Signorile, Imperial College London, Silwood Park Campus, SL5 7PY, UK or Zoological Society of London, Regents Park, London, NW1 4RY
The American Grey Squirrel is an alien invasive species that has been released many times in several areas across the world for recreational purposes. In Britain, following multiple introductions from the USA and Canada, grey squirrel populations have proven to be a major threat for both wildlife and agroindustry activities and their spread has been quick and unaffected by control programs. In both Ireland and the Piedmont in Italy, on the other hand, only one introduction, each of very few individuals, is supposed to have occurred within the last century and squirrel spread has proven to be relatively slow in both countries. The origin and founding size of the other three Italian populations is still unclear. We hypothesize that low genetic variation and inbreeding depression contribute comparably to differential expansion rates in Italy, Ireland, and the UK compared to ecological factors. The main aim of my PhD project is to evaluate the inbreeding coefficient of European grey squirrel populations by examining the heterozigosity at specific loci through microsatellite analysis of DNA. Outcomes will be correlated to spread rates. It will be important to include in this analysis the role played by ecological corridors and other ecological factors in squirrels’ spread and hence an analysis of several environmental determinants will be simultaneously carried out. If expansion rate of grey squirrels in Italy are strongly limited by low genetic diversity, it will be important to prevent the four separate Italian populations from merging and thereby potentially increasing their genetic diversity and speeding their joint expansion rate.
This Ph.D. project has been funded by the UK Natural Environment Research Council and will be undertaken at Imperial College London and the Institute of Zoology under the supervision of Dr Dan Reuman, Dr Chris Carbone, Dr Jinliang Wang, and Dr. Tony Sainsbury. Dr Sandro Bertolino of the University of Turin and Dr. Peter Lurz of Newcastle University are outside supervisors and collaborators.