Squirrels that have been previously fed by the homeowner or ones that notice some tasty food on the other side of that pesky screen will have no trouble tearing through for a snack. This is a page about squirrels chewing through window screens.
Squirrels Chewing Through Window Screens
Keeping Squirrels Out of Fruit Trees
Keeping Squirrels from Eating Tomatoes?
Keeping Squirrels Out of Your Attic
Keeping Squirrels From Chewing on a House
How to Stop Squirrels From Eating Suet Feeders?