Squirrels - Aavon Pest Control
Aavon Pest Control
49 Ryan Street
Stamford, CT 06907
Information can be viewed at http://animals.nationalgeographic.com/animals/mammals/squirrel/.
There are tricks to determine if you have one of these species of squirrels but it's usually identifying their droppings that are left behind and footprints in the dusty areas of the attics. Exterior access holes are always looked for. The holes are usually closest to the active noises in the walls or ceiling.
To determine active access points, placing something soft and somewhat loose in the holes usually gets pushed out visually within 24 hours. Oiled sunflower seeds can be placed in and around the attic in small trays using about a tablespoon and checked every couple of days. Mice will steal this food source as well but usually leave their droppings in the same area. You can set traps to get rid of the mice using a little bit of peanut butter and pushing the same oiled seeds into the peanut butter.
Trapping squirrels isn't hard, but I advise calling a trapper. They will know if the mothers are still caring for their litters and what all the options are and the best timing for each.