1. A collision avoidance assistance device for a vehicle comprising: a camera configured to acquire an image of an area around the vehicle; and a controller configured to: detect an image of an animal in the image of the area around the vehicle; determine a type of the animal detected in the image; retrieve behavior characteristics index values representing behavior characteristics of the determined type of the animal; calculate a future presence area of the animal based on the behavior characteristics index values; determine a probability of a collision between the animal and the vehicle based on the calculated future presence area of the animal; and perform a collision avoidance assistance function based on the determined probability of the collision between the animal and the vehicle.