Gut Bacteria Gives Grey Squirrels Competitive Edge Over Reds

A groundbreaking study reveals that grey squirrels outcompete red squirrels due to a more diverse gut microbiota, potentially explaining their dominance and destructive behavior.

Grey squirrels, introduced to the UK and Ireland from North America, outcompete native red squirrels for food and space, and carry a disease fatal to reds.
Researchers found grey squirrels have a more diverse gut microbiota, which may give them a health and dietary advantage over red squirrels.
A specific bacteria in grey squirrels helps them digest calcium from tree bark, possibly explaining their harmful bark stripping behavior.
The study, published in the Journal of Medical Microbiology, underscores the need for further research to protect red squirrels and forests.
Future strategies may include promoting healthy gut bacteria in red squirrels or developing new methods to prevent tree damage.