A new study has found that 71 mammal species have invaded Europe since Neolithic³ times, while another 30 species have successfully extended their ranges across the continent.

 

At least 58 of these species directly harm either human health or the environment, according to the report published in the journal Integrative Zoology⁴.

 

The study was conducted by Piero Genovesi and colleagues at the Institute for Environmental Protection and Research in Rome, Italy, and Riccardo Scalera of the Invasive Species Specialist group of the International Union for the Conservation of Nature (IUCN) based in Valby, Denmark.

 

The research follows up on previous work that examined which alien mammal species have invaded Europe since around 1500AD.

 

In the latest report, the researchers widened the study period to account for species that have invaded since 2007, the end of the previous study period, and before the 1500s, going back to Neolithic times.

 

They particularly focused on alien outsiders that now threaten native biodiversity.

 

Alien mammals have been introduced into Europe on at least 740 occasions, the study found.

 

For 635 of those, the researchers could reconstruct the date of introduction.

 

For example, wild boar were introduced into Sicily in the Neolithic age, while humans took lesser⁵ and greater white-toothed shrews to Cyprus, and Sardinia and the Balearics respectively, around 9000 to 8000 BC.

 

Most recently, in 2009, American red squirrels escaped into Denmark, probably from a commercial pet breeding facility.

 

In 2010, Canadian beavers were introduced to Belgium and Luxembourg, while in the same year raccoons arrived in Sweden.

 

Raccoons were also illegally released into Ireland in 2011.

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