Yes, groundhogs do hibernate—and they are actually among the few mammals that are considered “true” hibernators.

Quick Scoop: Do Groundhogs Hibernate?

  • Groundhogs (also called woodchucks) enter a deep hibernation to survive cold winters when food is scarce.
  • Their hibernation usually starts in late fall (around October or November) and lasts until late February, March, or even April depending on how cold the region is.
  • During this time, they stay in underground burrows below the frost line, where it’s more stable and insulated from freezing temperatures.
  • While hibernating, their body temperature, heart rate, and breathing drop dramatically, putting them into a state called torpor so they can live off stored body fat instead of eating or drinking.
  • In very mild climates, some groundhogs may hibernate for a shorter time or in rare cases not truly hibernate at all, but in most of their range they do.

How Their Hibernation Works

  • Before winter, groundhogs eat heavily through summer and fall, building up thick fat reserves that fuel their long “winter sleep.”
  • Just before hibernation, they dig or retreat to deeper chambers in their burrows, often below the frost line, then seal themselves in with soil and plant material for insulation.
  • In hibernation:
    • Heart rate can drop to just a few beats per minute.
* Body temperature falls close to the surrounding ground temperature, far below their normal warm-blooded level.

* Metabolism slows so much they can go months without eating.
  • They may briefly rouse during winter for short “check-ins” on their bodies, then return to deep sleep until spring.

When Groundhogs Hibernate and Wake Up

  • In colder northern areas (like Maine or similar latitudes), groundhogs may hibernate roughly mid–October to early or mid–April, close to 5–6 months.
  • In mid-latitudes (like Pennsylvania), they might hibernate around November to late February or early March.
  • Further south (like South Carolina and other mild regions), hibernation can be only about two months long.
  • Famous “Groundhog Day” appearances in early February usually line up with brief mid-winter arousals rather than the animal being fully active for the season.

Groundhogs in Burrows: The Winter Setup

  • Groundhogs dig complex burrow systems with multiple chambers; they use the deepest, well-insulated rooms for winter hibernation.
  • These chambers are lined with grasses, leaves, and other plant material, and then covered or plugged with soil to keep warmth in and cold air out.
  • While underground, they rely solely on fat reserves, not stored food, which is why their summer and fall foraging is so intense.

Why This Is a “Trending Topic”

  • Every year around February 2 (Groundhog Day), interest spikes in questions like “do groundhogs hibernate” and “where have they been all winter,” especially in the U.S. and Canada.
  • Wildlife, nature, and science outlets often publish seasonal explainers about groundhog hibernation around this date, tying real biology to the holiday tradition.
  • Recent articles continue to highlight groundhogs as model animals for studying hibernation—how they manage energy, survive with low body temperature, and time their emergence with changing climate patterns.

TL;DR: Groundhogs really do hibernate, and they do it in a deep, energy- saving state underground from about late fall until late winter or early spring, living off stored fat instead of eating.

Information gathered from public forums or data available on the internet and portrayed here.