Ground squirrels live communally, with 2 to 20 or more individuals occupying a single, complex burrow system. While a single entrance might look isolated, it is often part of a larger, interconnected network that can house multiple, related individuals.
In periods of high winds, ground squirrels retreat to their burrows. California ground squirrels live in underground burrows and form colonies of 2 to 20 or more animals. Each ground squirrel burrow system can have several openings with scattered soil in front.
Mating occurs from January through July, with peak activity in March through June. Following a gestation period of about 30 days, an average of 6-7 young are born (range 3-15). Litter size is correlated inversely with latitude (Chapman and Lind 1973). Females produce 1 litter per yr.
For best control, use burrow fumigation about 2 to 3 weeks after the first ground squirrels emerge from hibernation. Because ground squirrels feed almost exclusively on green vegetation early in the season, poisoned grain baits are generally not effective until late spring or early summer.
For the species known scientifically as Marmota monax, and whose common names include woodchuck and whistle pig, burrow digging is a solo effort. For a greater part of the year, burrow occupancy is limited to one groundhog per unit.
Blocking groundhog holes
If there is concern that a particular burrow is weakening the foundation of a shed or walkway, the opening can be sealed to prevent access at the vulnerable point, however this will not eliminate the burrow system. Groundhogs have complex burrows with multiple openings.
Even in the summer and fall, groundhogs prefer to remain hidden when not foraging for food. While they're most active during the day, woodchucks only emerge for up to two hours each day. Groundhogs usually have two separate burrows, one for summer (grassy field area) and one for winter (wooded area).
The 5-7-9 rule is a guideline for placing bird feeders to deter squirrels, suggesting they should be 5 feet off the ground, 7 feet from jump-off points (like trees or fences), and 9 feet below overhanging branches, based on a squirrel's jumping and leaping capabilities (5 ft high, 7 ft horizontal, 9 ft drop). Following these measurements creates an "escape room" challenge that makes it difficult for squirrels to reach the seed.
2) Encourage Predators: Many natural predators, such as coyotes, foxes, bobcats, badgers, hawks, and snakes, eat ground squirrels. Predators are beneficial in reducing ground squirrel numbers and preventing them from invading marginal habitats.
Ground squirrels live in colonies that may grow very large if left uncontrolled. They are active during the cooler times on hot days and sunny periods during the cooler months; they are usually most active in morning and late afternoon.
A squirrel's worst enemies include natural predators like hawks, owls, snakes, foxes, and coyotes, but in many areas, humans (through vehicles and habitat destruction) and domestic cats/dogs pose the greatest threat, while in the UK, the invasive grey squirrel is the primary enemy of the native red squirrel.
Ground Squirrel Life Expectancy
The average lifespan for the California ground squirrel is 3 to 4 years in the wild, but they can live as long as 6 years. In captivity, the recorded lifespan for the ground squirrel is 10 years.
The breeding season extends from early March to late April, after hibernation. A mated pair remains in the same den throughout the 32-day gestation period. The male leaves the den as birth of the young approaches, in April or May. One litter is produced annually, usually containing two to six blind and hairless babies.
Squirrel birthing and mating season occur twice a year. Squirrel mating season happens once between December and February, then again in late June through August. With the gestation period lasting 38 to 46 days, female squirrels will give birth in early spring (February through April) or late summer (August/September).
Although squirrel bites are mostly benign and infrequently encountered in medical practice, they may lead to necrotizing soft tissue infections which can be life‐threatening.
How to Get Rid of California Ground Squirrels Humanely
Groundhogs have short, powerful limbs and thick claws. They have small ears and black eyes. Males are typically larger than females. The average lifespan of a groundhog is 3 years.
Gray squirrels are great jumpers, as well. They can leap 6 feet or more from one branch or tree to another. They can also vault a distance of 16 feet when dropping from one limb to another. In addition, a squirrel can spring vertically from the ground at least 5 feet high.
It's always on Feb. 2, which in 2025 lands on a Sunday. Punxsutawney Phil - as well as other groundhog predictors around the nation - will predict the forecast early in the morning. (Typically around 7:30 a.m.)
If you fill in a groundhog hole, there's a good chance it will dig a new hole. To truly rid your property of a groundhog, you should always reach out to a professional wildlife control operator.