Predicting the spread of the American grey squirrel (Sciurus carolinensis) in Europe: A call for a co-ordinated European approach

摘要: Abstract The introduction of the American eastern grey squirrel ( Sciurus carolinensis ) in Europe is causing a dramatic decline native European red vulgaris ), due to competition. We used spatially explicit population dynamics models illustrate potential expansion from Italy, only continental country with species, into neighbouring countries. Simulations started known distributions 1996 and modelled spread for next 100 years two different scenarios. One “best case” which random seed crop pattern poor, good mast crops was simulated concomitant effects on fecundity mortality one “worst scenario poor were not included. In best case scenario, it will take 30–40 squirrels start invading Alps about 70–75 cross border between Italy France. First populations Switzerland are predicted 2051–2066. worst be significantly faster: species reach France 2026–2031 2031–2041. Removing three likely postpone invasion but Large areas contain potentially habitat squirrels, France, belong most Eurasia simply matter time. This represent serious risk conservation have implications national forest operations. However, policy towards introduced still lacking. There therefore need co-ordinated approach management other species.