Have a warm puffy coat? Thank a bird for that

Like many kids growing up in Northeast Ohio, I loved the snow. It meant building igloos and snowball fights, sledding and a homemade football game we called "goal line," which basically reduced the football field to five yards as an excuse to tackle each other in the snow. I think, in a way, I always took pride in being tough — going to bitter cold Browns games, shoveling the driveway and taking care of the barn animals. It was a way of life for us, and I didn't worry much about cold weather and snow. However, now as a "responsible adult," I do worry about the cold and snow. Last year, during one cold spell, our pipes froze and broke. Last week, when trying to start the dishwasher, it broke. The small heating unit in the four-season room? Broke. My car last weekend? Broke. I lacked the courage to check the hot tub, but I did clean the ice off of it — and the snow shovel ... broke. I no longer associate the cold with a neighborhood game of "goal line." Now I just wait to see what will break, how much it will cost to fix and ask myself why I still live in Northeast Ohio. However, compared to the birds and other wildlife who endure the cold, my complaints seem pretty small. Maybe even petty. So how do birds — the brave ones that either don't migrate at all (such as our woodpeckers), those species where only some individuals migrate (like robins and great blue herons) or birds that actually migrate into our area (like snow buntings and dark-eyed juncos) — survive these harsh conditions? It's natural to worry about birds and kind to put out some extra seed or suet ... or maybe set up a heated bird bath. It certainly does help, and the birds appreciate it, especially in times of significant snow cover. However, they have evolved to handle these conditions and while they can't sit by a warm fire and sip on hot chocolate, they do have natural adaptations that help them survive. That doesn't mean it's easy for them — it's tough, they're tough — and that's another reason I have so much respect for birds and other animals. Insulating Feathers Birds have layers of feathers (especially down and contour feathers) that trap air close to the body. That trapped air acts like a blanket, slowing heat loss. Humans have copied this trick by filling our jackets and sleeping bags with down from ducks and geese (though the down industry has also raised ethical questions, and many people now choose certified or synthetic alternatives). Seasonal Metabolic Adjustments An article in Avian Research found that small passerine birds can acclimate to temperature changes through seasonal metabolic adjustments. Through complex processes, researchers found that birds can "adapt to seasonal or just temperature changes through some physiological and biochemical thermogenic adjustments, which would be beneficial to cope with natural environmental changes" and that "metabolic adjustment might be the primary means by which small birds meet the energetic challenges triggered by cold conditions." Hypothermia and Temperature Regulation In this process, birds reduce their body temperature to conserve energy. A report in the National Library of Medicine found that "birds such as parids (titmice and chickadees) can use facultative hypothermia, a process in which body temperature is actively down-regulated to a specific level, to reduce heat loss and thus save energy. During cold winter nights, these birds may decrease body temperature from the normal 42°C down to 35°C, or even lower in some species." They also reduce the temperature in their feet to near freezing. The study also found that during this state, birds are unable to move, making them more vulnerable to predators. The risk seems to be worth it, as researchers concluded that "the use of nocturnal hypothermia at night is paramount in these biomes, as it would increase winter survival for a small northern bird by 58 percent over a winter of 100 days." Countercurrent Heat Exchange Winter is a great time to see gulls, but just watching them out there on the cold lake and ice makes me wonder how these birds survive these conditions. Have you ever wondered how their feet don't freeze standing on the cold ice? The Cornell Lab of Ornithology describes the process, called countercurrent heat exchange: "Keeping an entire foot warm requires a tremendous energy cost. Instead, these birds allow the foot to approach freezing temperatures. Blood is still supplied to the foot, however, so the birds use a countercurrent heat exchange system — cool blood coming back from the foot travels through veins grouped around arteries that are sending warm blood from the body to the foot. Heat is transferred from the warm arteries to the cool veins." Fortunately, bird feet are mostly tendons and bones, with very little nerve and muscle tissue. You may also see ducks, geese gulls, and other birds standing on one leg or tucking their bills under their back feathers to keep warm. Behavioral Strategies The U.S. Fish & Wildlife Service has identified several behaviors — such as shivering, fluffing feathers, caching food, roosting and cuddling — that birds use to keep warm in winter. When you see a bird fluffing its feathers, it's not trying to look mighty — it's trying to stay warm by trapping pockets of air around its body. It's like puffing up a down jacket to make it warmer. Smaller birds, like tree swallows and kinglets, will also cuddle together in shrubs and trees to share body heat. Caching food—the process of storing food for later use, especially during cold, snow-covered days — is an excellent strategy for getting the calories they need for energy and warmth. How do they remember where they hid all their nuts and seeds? Remarkably, they can shrink and grow their brains. The Cornell Lab of Ornithology notes that chickadees change their brain size by season: "In autumn, the birds need a strong memory mechanism for re-locating their secret caches. So, the hippocampus regions of their brain add more neurons, increasing volume by about 30 percent. As winter fades, temperatures rise, and food is more abundant, the chickadee's brains shrink down again." Until Spring! Birds and other animals have evolved over millions of years to handle their environment. They use every adaptation and behavioral strategy available to survive the difficulties of winter. Personally, if I were a bird and could fly south, I'd probably choose that option — but they know what they're doing, and they've "decided" that staying here gives them the best chance of making it to spring. I suppose it's the same for us. I don't go south for the winter because my resources — my home and my job — are here. It's just something we all have to get through. Forty-two days until spring! Black River Audubon Community Showing of Ripples of Plastic The Black River Audubon, in conjunction with the Lorain County Metro Parks, is presenting a special showing of the documentary "Ripples of Plastic." Birds are often the first to show us when our environment is in trouble — and plastic pollution is no exception. This award-winning documentary explores how plastic moves through waterways and food webs, affecting wildlife and human health. Sunday, February 22, 2pm French Creek Nature Center This is a free event, but please register at blackriveraudubon.org.