From food consumption to feather adjustments and shivering, birds use a variety of techniques to stay warm during winter.
Food is the most essential element, providing birds with the energy, stamina and nutrition they need. To stay warm, birds will expend energy very quickly, some losing up to 10% of their body weight on extremely cold nights. An ample supply of high-calorie foods, such as black oil sunflower seeds, peanuts and suet can be crucial to a bird’s survival.
We can play a vital role during cold conditions. At these times, a reliable supply of food can mean the difference between life and death for a bird.
Most birds will also keep warm by adjusting their feathers to create air pockets. You will often notice the birds look fatter or ‘puffed up’ during cold weather. This is because the birds are fluffing up their feathers; the more air space, the better the insulation.
Staying warm is not all about food and feathers, though. Some birds perch on one leg at a time, drawing the free leg to their chest for warmth. Most birds will shiver to convert muscular energy into heat for the short term, but the energy must be replenished shortly thereafter.
While birds are equipped to withstand most winter weather, survival can be made easier by providing food, a heated, open source of water and protection from the elements with natural plant cover or a roosting box.