Winter is coming, the days are darkening, the temperature drops and the wildlife neighbours that were once in abundance slowly disappear from the landscape. The rules in nature are simple, get out and migrate, find a way to cope with the cold, or die. Despite this ultimatum, on my snow muffled walks there is usually one call that pierces through the frigid air “chicka-dee- dee-dee”, the adorably dapper black-capped chickadee. Many regard the chickadee as a sweet little songbird without ever considering its amazing ability to persevere and survive. When most birds flee to somewhere warmer these tiny neighbours tough it out. In order to survive they make changes to their body, also known as adapting, in some incredible and unusual ways.
The first, and more well-known adaptation the chickadees have is their warm and plentiful feathers. Chickadees can surprisingly squeeze through holes the size of a quarter, most of the size we see when looking at a chickadee is just feathers. These will insulate them from the cold weather, just like the down feathers in your jacket. Unlike our jackets, chickadees can puff up their feathers with their muscles trapping more air in them and increasing their insulation factor. This is why chickadees appear plumper and more round in the winter months.
Speaking of plump, chickadees can remarkably eat enough food to increase their body weight by 10% every day in winter. This is all stored as fat, which the chickadee will burn during the cold winter nights to keep their metabolism up and warm their little bodies. Imagine gaining between 10-20 lbs every day and then losing it every night while you sleep. Now if you imagine trying to find enough food to eat in the cold barren landscape of winter to gain that much weight you might be feeling a little perplexed.
Most animals can’t survive winter due to lack of food. Do chickadees have secret food stashes that the other animals don’t know about? They most certainly do. These are called food caches, where chickadees have stored food they have found earlier. Caching food is not unique to chickadees, lots of rodents do this, weasels too. What is unusual is the chickadee’s ability to remember the location of over 400 caches. I can’t even remember where I left my car keys on some days. Scientists discovered this amazing feat of memorization is due to the chickadee’s brain increasing in size in late summer. It grows more neurons in the part of the brain used for memorization and then come spring, it will lose those neurons again.
If you still aren’t impressed with these winter warriors’ ability to adapt they have one more trick up their wing. During the cold nights they drop their body temperature and go into a controlled hypothermia called torpor. This allows that fat layer they gained from eating at their food caches to be just enough heat to survive the chilly nights.
The next time you see the cute little ball of fluff known as the black-capped chickadee in winter I hope you tip your own cap at these fierce and underrated champions of winter survival.
