Squirrels are a familiar sight across Wisconsin, often seen scampering through yards and parks. Understanding their reproductive cycles provides insight into the rhythms of local wildlife. These small mammals exhibit specific patterns for when they raise their young, adapting to environmental conditions throughout the year.
Breeding Seasons for Wisconsin Squirrels
Wisconsin is home to several squirrel species, including the eastern gray squirrel, fox squirrel, and red squirrel, each with distinct breeding timelines. Eastern gray squirrels, prevalent throughout the state, have two litters annually. The first litter is born between late March and early April, with a second litter arriving from late July to early August. After a gestation period of about 40 to 45 days, female gray squirrels give birth to two to seven young.
Fox squirrels follow a similar pattern, mating in mid-December or early January and again in June. Their first litters appear as early as late January, with most births occurring in mid-March. A second litter arrives around July, though fox squirrels in Wisconsin rarely produce two litters within the same year. Their gestation period is around 44 to 45 days, resulting in an average of three young.
Red squirrels breed slightly later in the spring, starting around March. They may produce two litters in a year, with the first in April and the second in August. The gestation for red squirrels is 36 to 42 days, and a litter contains around three babies. The young of all these species are born blind and hairless, remaining dependent on their mother for several weeks before venturing out independently.
Factors Influencing Birthing Cycles
The timing and success of squirrel birthing cycles are linked to environmental and biological factors. Food availability plays a role, as abundant food sources support the energy demands of reproduction and raising young. A plentiful supply of nuts and seeds influences both the timing and success of breeding.
Weather conditions also have an impact on when squirrels have their babies. Mild winters can lead to earlier breeding activity, while prolonged cold snaps can delay the onset of the reproductive season. Temperature and precipitation affect the timing of births and even the survival rates of young.
The amount of daylight, or photoperiod, serves as a cue that triggers the reproductive cycles in squirrels. As days lengthen in spring and shorten in late summer, these changes initiate the animals’ breeding readiness. While general patterns exist, slight variations in birthing cycles can occur between different squirrel species due to their unique adaptations and habitat preferences.
If You Find Baby Squirrels
Encountering baby squirrels can be an occurrence, and knowing how to respond is important. If you find young squirrels that appear alone, it is best to observe them from a distance. Mother squirrels leave their young temporarily and are nearby, returning to care for them.
Intervention may be necessary if you notice signs of distress, such as visible injury, extreme cold, or the presence of flies indicating neglect. If a baby squirrel is uninjured but has fallen from a nest, you can attempt to reunite it with its mother. Place the baby in a small, shallow box lined with a soft cloth, and if it’s chilly, include a warmth source like a warm water bottle wrapped in fabric.
Position the box at the base of the tree where the nest is located, during daylight hours when the mother is active. Keep pets and people away from the area to avoid scaring the mother. If the mother does not retrieve the baby after a few hours, or if the baby is injured or orphaned, contact a licensed wildlife rehabilitator in Wisconsin. Attempting to raise wild animals without proper permits is illegal and can harm the animal’s chances of survival in the wild.