20 January 2023

Squirrels can be annoying at bird feeders but their expressions can be endearing.

If you think our eastern gray squirrels (Sciurus carolinensis) are cute you ought to see the native red squirrel of Europe (Sciurus vulgaris).

Sat at my desk trying to concentrate but… pic.twitter.com/QhUHkoBZPW

— Ian Carter (@IanCarter67) June 8, 2022

These native squirrels have been declining in the UK, Ireland, and Italy due to competition from eastern gray squirrels, imported from North America in the 1890s and spread by humans to new locations(*).

However, the native red squirrels are stabilizing in Scotland, in part because European pine martens (Martes martes) are increasing and they selectively prey on gray squirrels.

The European pine marten is pretty cute, too.

p.s. Gray (grey) squirrels are invasive in the UK but a 2016 study found that their populations are genetically distinct from their neighbors and they didn’t invade new places on their own. Humans spread them!

One of the worst offenders at spreading grey squirrels was the 11th Duke of Bedford, Herbrand Russell. Russell was involved in many successful animal conservation projects, but released and gifted many grey squirrels around the UK from his home at Woburn Park.

Russell also released populations [of grey squirrels] in Regent’s Park, likely creating the London epidemic of greys. 

— Imperial College London: Don’t blame grey squirrels: their British invasion had much more to do with us

(photos from Wikimedia Commons; click on the captions to see the originals)