First of all, large prey birds prey on squirrels, especially night birds, where their main enemy is a filbert. But the main enemy for squirrels is the marten, from which it is almost impossible to hide.
From feathered predators, the protein is protected in an interesting way. When attacked, she begins the game of hide and seek and runs up the trunk of the tree, as always in a spiral, hiding behind the trunk from the eyes of predators. Therefore, the attacker is forced to fly in a circle of a larger diameter and therefore loses in time. Night predators have more chances, suddenly attacking a sleeping animal.
If predators do not cope with their case and the number of proteins increases, then they gather in large flocks and go in search of food. During the campaign, many of the proteins die, as they often encounter obstacles such as wide rivers.
A huge crowd of squirrels does not stop it and they swim across them, raising their fluffy tails. But if the tail accidentally gets wet, then the protein most likely drowns, as it can not withstand the weight of the wet tail.