This last weekend, Marg and I went up to Mount Abram to ski (Margaret is on Patrol there, I went to ski). Anyway in the morning, it was frakking cold (-11 at the top of the mountain). And I was shivering until we got to skiing. This only relates to a Bee Blog post with the question; how the heck do bees (an insect that is most likely tropical in origin) get through the winter in Maine?
Honey Bees cluster together in the winter to keep warm, they do this when the temperature of the air inside the hive drops to 57 degrees Faranheit. The temperature inside the winter cluster is kept fairly low (so the bees aren’t burning through all that honey they stored up too fast), between 57 and 85 degrees. They do this by shivering, just like I was at the top of Abram. They shiver their flight muscles which warms up their thorax and head.
Here is a great video from the BBC with an infrared camera and a queen Bumble Bee warming up for flight in the spring:
The shivering occurs as the bee disconnects it’s flight muscles from it’s wings. The mechanism is similar in Honey Bees as it is in Bumble Bees.
Here’s a good article from American Scientist that is a little more specific on individual bee scale thermoregulation (for those that are really interested):
Bees also have to take cleansing flights on warm days in the winter to evacuate their bowels, and keep things sanitary in the hive. If they get too cold they can’t fly, and they have to land to warm up their flight muscles. If they land in the snow, its all over.
Here’s a video of some bees that have died in cleansing flights:
Some of these bees probably have also died in the hive and were carried out by mortuary bees.
If you notice in the video that the hive is all black, that’s because we covered it with a weather barrier that we got from Margaret’s dad. This is mostly to keep the wind out, but also to help keep the hive warm.
Here’s some pictures of the mortal costs of the winter:
Listening to the side of the hive is reassuring, however we can still here them buzzing in there!