1. They Get Hungry
While squirrels are primarily diurnal, they may wake up in the night and feel hungry for a midnight snack. Squirrels spend a lot of their daylight hours foraging for food, but they don't do this at night. For one thing, their vision isn't good at night, so they would have trouble finding food. For another, there are many predators active at night that would love to make a snack of the squirrel. Squirrels collect food and store it in safe places near their dens or dreys to feed on through the winter. If a squirrel wakes up hungry in the middle of the night, it will probably go to one of its stores to find a snack, then go back to bed.
2. They Have To Urinate or Defecate
At some point in your life, you have probably woken up in the middle of the night and found that you had to go to the bathroom. The same thing can happen to squirrels. The difference is that squirrels don't have to go far. They don't have a specific area that they designate as a latrine, so they may excrete in the nest or nearby it.3. They Hear a Warning Call From Other Squirrels
There are many nocturnal predators that would love to catch and eat a squirrel if they could get one, including owls, coyotes, foxes, and even house cats. Because most squirrel species are diurnal, nocturnal predators don't often get a chance to eat them. However, sometimes a chance encounter occurs between a squirrel and a predator. Squirrels are prey animals, but they aren't completely helpless. When faced with a perceived threat, squirrels give a series of warning calls. It is not clear whether these cries are meant to intimidate predators or warn other squirrels of their presence. However, if a squirrel hears a warning call from another of its species, it will probably get up right away and start looking for the potential threat.4. They Hear a Loud Noise
Squirrels are sensitive to any warning sign that a predator may be nearby, such as loud noises. If a squirrel hears a loud noise at night, it will immediately wake up and go on the alert. For example, if you have squirrels in your attic and you go up there at night and disturb them, they will probably startle awake and get ready to either defend themselves or flee. Most humans do not eat squirrels, but the squirrels don't know that, and, being wild animals, they will assume that you are a threat. Squirrels are small, but they have sharp teeth and claws that they can use to defend themselves if necessary. They aren't known to have rabies, but they may spread other blood-borne pathogens through their bites. As prey animals, squirrels prefer to run away from danger if possible, but if cornered, they may fight to defend themselves.