Lo scoiattolo grigio americano, considerato a livello europeo una specie aliena invasiva, è una minaccia per lo scoiattolo rosso indigeno. In tutte le zone in cui arriva si appropria delle scorte di cibo della specie rivale e provoca l’estinzione della specie autoctona, di dimensioni più piccole, e notevoli danni agli ecosistemi forestali.
In Gran Bretagna e in Irlanda la specie d'oltreoceano è già la più diffusa e se ne trovano esemplari anche in nord Italia.
L'organizzazione zurighese Wilde Nachbarn (vicini selvatici) ha lanciato in proposito una campagna di sensibilizzazione e avvistamenti di scoiattoli rossi o grigi possono essere segnalati al sito (in tedesco) dell'organizzazione www.wildenachbarn.ch.
ATS/Bleff
Wikipedia:
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