Groundhog or Woodchuck — Facts, Photos and Control
February 2nd is the day each year in which we look towards a giant rodent to find out how much
more winter we'll have to endure. This year, we probably know the answer: winter hasn't been
According to tradition, the groundhog, Marmota mona, also known as a woodchuck or whistle pig,
peeks out of its burrow on February 2nd and checks to see if it has a shadow. If sunny enough for a shadow,
the groundhog will return to the comfort of its burrow, and winter will continue for an additional 6 weeks.
The name woodchuck has nothing to do with wood or chucking. The name is derived from the Algonquian
name for the critters, wuchak.
|Groundhog or Woodchuck
||Various shades of brown
||Coyotes, Foxes, Dogs
This stout-bodied rodent weighs up to 13 pounds and has a body length of up to about 20 inches and
a short, bushy tail up to 18 cm (7 inches) long. Thick fur on the upper parts ranges in colour through
various shades of brown; the feet are darker, and the underparts are buff. Melanistic (nearly black)
and albino individuals sometimes occur in some populations. Found from the eastern and central
United States northward across Canada and into Alaska, they most commonly live along forest edges
abutting meadows, open fields, roads, and streams, but they are occasionally also encountered in
dense forests. The groundhog is solitary except in the spring.
Groundhogs have four incisors, shaped like chisels, two upper and two lower of which the upper two
continue to grow at the rate of 1/16 of an inch every week! To keep the growth of the front teeth in
check the groundhogs have to constantly chew or gnaw on leaves or grass. They also spend a good
amount of time nibbling at trees or roots so that the teeth can be worn down. The groundhog defends
itself from predators by using its two large incisors and claws.
Though they spend most of their time on or under the ground, groundhogs can also climb trees.
Both male and female groundhogs tend to occupy the same territories year after year. For females,
there is very little overlap between home ranges except for the late spring and early summer, as
females try to expand their territories. During this time, their ranges may overlap by as much as 10
percent. Males have non-overlapping territories as well, though any male territory coincides with 1
to 3 mature females' territories.
Interactions between female groups — even when those groups are shared by the same adult
male — are rare and aggressive. Even though daddy groundhog doesn't live at home, from the
breeding season through the first month of the infants' lives, he visits each of his female groups
Groundhogs are active during the day. In summer they commonly feed in the early morning and the
late afternoon, spending the rest of the day sleeping or basking in the sun. In late summer they begin
to put on weight in preparation for the move to their winter dens, often located in wooded areas.
They hibernate from October through March. While hibernating, a groundhog's body temperature
drops from 99°F to 40°F, and its heartbeat drops from 100 beats per minute to 4 beats per minute!
Groundhogs live in extensive burrows two- to six-feet deep and up to 40 feet long that contain
numerous chambers with specific functions, such as for nesting or for wastes. You can usually
spot the main entrance by an adjacent large mound of dirt, which these animals use for observation
and sun-basking. In addition, there may be as many as five other openings to the den.
Mainly vegetarians, groundhogs feed on a variety of grasses and chickweeds, clover, plantains,
and many varieties of wild and cultivated flowers. They eat blackberries, raspberries, cherries, and
other fruits, along with the bark of hickory and maple trees. Of course, to the chagrin of gardeners,
groundhogs love fresh produce, as well. They will even eat grasshoppers, June bugs, and other large
Woodchucks do not mate until their second year. The average life span for a woodchuck in the
wild is five to six years. Males and females breed in March or April, after which they have no further
contact. The female grounhog raises the chucklings alone.
Woodchucks give birth from early April to mid-May following a 32-day gestation period. One litter
contains four to six kits. The young open their eyes at four weeks and are weaned at 6 weeks, when
they’re ready to leave the burrow with their mother. In the fall the young woodchucks venture off to
seek their own territories.
Infants stick around home for only about 2 to 3 months after being born and then they disperse and
leave mom's burrow. However, a significant proportion, about 35% of females stick around longer,
leaving home just after their first birthdays, right before mom's new litter arrives.
What do groundhogs eat? Everything from flowers to vegetables. Favorite foods include alfalfa, clover,
peas, beans, lettuce, broccoli, plantain, and soybeans. Groundhogs will often devour your seedlings
before they even have time to grow. f you don’t have vegetables around, groundhogs will settle for twigs,
bark, bugs, and blossoms.
These critters may have been attracted by your garden full of tasty plants. Encourage them to go
Sprinkle blood meal, ground black pepper, dried blood, or talcum powder around the perimeter of
your garden. You can try using hair clippings as well.
Puree and strain hot peppers and garlic, mix them with water and enough liquid soap to make it stick,
and spray it liberally around the garden.
Put some harmless but strong-smelling substance just inside the burrow (such as urine-saturated
clumps of kitty litter). Loosely seal the entrance, so the smell stays inside the burrow.
Would you eat lettuce tossed with bobcat urine? Neither would a woodchuck! Fox, coyote, wolf, and
bobcat urines are among the forbidding predator scents now sold as groundhog repellents.
Keep undergrowth and grass cover low to deter groundhogs.
Groundhogs are always looking for vacant burrows. Close down their tunnel systems. Bury 3-foot
square panel of welded wire, centered over the entrance hole before an abandoned burrow is
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