When you’re out herping year-round, you start to notice the seasonal rhythms of reptiles and amphibians. In spring and summer, the woods, swamps, and rocky outcrops are alive with activity, snakes basking on trails, turtles crossing roads, frogs calling at night. But as the temperatures dip in fall, many herps seem to vanish. Where do they go? Are they hibernating like bears and bats? Not exactly. In the reptile and amphibian world, the term you’re looking for is brumation. And while it shares similarities with hibernation, there are some key differences worth understanding.

Hibernation: The Classic Cold-Weather Survival Strategy

Most people are familiar with hibernation as it relates to mammals. Bears, groundhogs, and bats are the classic examples. Hibernation is a state of prolonged dormancy in which an animal slows its metabolic rate to conserve energy through the harsh winter months.

In true hibernation, body temperature, heart rate, and breathing rate drop dramatically. The animal essentially shuts down and remains in a deep sleep until temperatures rise again and food becomes available. Mammals that hibernate typically don’t wake up for long stretches, sometimes months at a time.

Brumation: The Reptile and Amphibian Version

Reptiles and amphibians are cold-blooded (ectothermic), meaning they rely on external sources of heat to regulate their body temperature. Because of this, they don’t hibernate in the strict mammalian sense. Instead, they enter a state called brumation.

During brumation, herps slow down their metabolism just like hibernating mammals, but they don’t go into a continuous, deep sleep. Instead, they may remain sluggish and inactive for long periods, but can wake up sporadically, drink water, or even move around during brief warm spells.

For example:

• Snakes may coil up in communal dens, sometimes with dozens of individuals gathered in the same crevice or burrow.
• Turtles bury themselves in the mud at the bottom of ponds, slowing their metabolism to survive with limited oxygen.
• Frogs find leaf litter or soil to burrow into, some even producing natural antifreeze in their bodies to survive freezing temperatures.

Field herping enthusiasts often mark the brumation period as the “quiet season.” It’s that stretch of late fall through early spring when reptiles and amphibians are far less visible, waiting out the cold until conditions improve.

Key Differences Between Brumation and Hibernation:

1. Depth of Dormancy

• Hibernation: A deep, continuous sleep-like state with very limited waking.
• Brumation: A slowed-down state of dormancy, but animals may stir, drink water, or even briefly bask if a warm day occurs.

2. Species Involved

• Hibernation: Mammals such as bears, bats, and rodents.
• Brumation: Reptiles and amphibians—snakes, lizards, turtles, salamanders, and frogs.

3. Metabolic Needs

• Hibernation: Animals live off stored fat reserves and do not eat or drink.
• Brumation: Reptiles and amphibians may still drink water occasionally but typically stop eating since their slowed metabolism can’t process food efficiently.

4. Environmental Cues

• Hibernation: Triggered by cold temperatures and food scarcity.
• Brumation: Driven not only by temperature but also by changes in daylight (photoperiod), which signal the changing seasons.

Why Brumation Matters

Understanding brumation isn’t just trivia, it’s crucial for conservation and captive care. In the wild, brumation cycles help synchronize breeding. Many snakes and turtles, for example, emerge from their winter dens ready to mate. Without this natural downtime, their reproductive cycles would be disrupted.

For herpers, knowing when brumation occurs helps set expectations. Late fall through winter isn’t the ideal time for spotting snakes or lizards in the wild, but it’s a reminder of how finely tuned these animals are to their environments.

Closing Thoughts

While the terms hibernation and brumation often get used interchangeably, they’re not quite the same. Hibernation is the deep, continuous dormancy of mammals, while brumation is the cold-weather slowdown of reptiles and amphibians. Both are survival strategies, but brumation reflects the unique biology of herps and their reliance on external heat sources.

So next time you’re field herping in early spring and spot the first garter snake basking on a log or the first chorus frog calling, you’ll know: these creatures have just come out of brumation, ready to eat, breed, and kick off another season of activity.