How Bees Stay Warm in the Winter

It’s been a wild winter here in Santa Cruz, with back-to-back atmospheric storms, hail, and even snow in some areas! With each storm, I can’t help but feel a little anxious about how my bees are handling it all. But thankfully, honey bees are incredibly resilient creatures with remarkable mechanisms to keep warm and cozy inside the hive, no matter the weather outside.

 A rare snowstorm in the Santa Cruz Mountains

The Winter Cluster: A Natural Survival Strategy

To survive the cold months, a honey bee colony contracts into a tight, well-insulated cluster of bees, about the size of a basketball. This cluster acts like a living incubator, protecting the queen and any brood (developing bees) from the freezing temperatures. The bees on the outer surface of the cluster work to maintain a temperature above 50°F, which is just warm enough to keep all colony members alive and active.

Inside the cluster, bees generate heat by isometrically contracting their flight muscles—a movement that doesn’t actually involve flying but creates warmth. This allows the bees to maintain an internal cluster temperature of about 95°F, the perfect temperature for raising new bees and keeping the queen comfortable.

Honey: The Fuel for Winter Survival

So, how do bees power this incredible heat production? Honey. The bees work tirelessly during the spring and summer months to ensure they have enough honey stored away to fuel them through winter. Honey acts as both a food source and a great insulator, helping the bees retain the heat they generate inside the hive.

For beekeepers, ensuring there’s enough honey stored is critical to a colony’s winter survival. Not only should there be plenty of honey, but the honey frames should be strategically positioned around the brood nest and above it (if the hive is in two boxes) to maximize heat retention.

Checking on the Bees After a Storm

After each storm, especially with the intense rains and 80 mph winds we’ve experienced recently, I make it a priority to check on my bees. It’s always a bit nerve-wracking to see how they’ve weathered the storm, but their natural resilience and the careful preparation we’ve done throughout the year give me confidence that they’re handling it well.

If you’re a beekeeper, as you prepare your hives for winter, remember to keep an eye on honey stores and make sure the bees have enough fuel to stay warm. The placement of honey frames can make all the difference when it comes to keeping the hive toasty and thriving through the cold months.

Now, time for me to check on my bees after this week’s wild weather. Wish me luck!