Those stinkers have been digging around on the fire escape. One looks dead for sure.
I found this online...
cayenne pepper squirrel repellent
Recipe for squirrel repellent:-
1) 1 bottle (small) hot pepper sauce
2) 1 gallon water
3) water retentative (available from plant nursery) or 1 teaspoon of mild liquid detergent such as dishwashing detergent.
Spray this repellent on plants or anything you would like protected from chewing. Many commercial products designed to repel rodents are not effective. In fact, some say the animals actually eat more of the plants after the repellent is applied.