The Ruffed Grouse has both behavioral and physical strategies for dealing with the cold, snow and ice of New England winters. Three of the physical changes that take place in the fall are evident by looking closely at a grouse’s legs, feet and beak. The feathers on its legs grow thicker and further down towards its feet, to provide better insulation. Small comb-like growths of skin, called pectinations, develop along either side of each toe. These increase the surface area of a grouse’s foot, and serve as snowshoes in deep snow. They also help the grouse cling to icy branches while it quickly snips off poplar and other buds at either end of the day. And on its beak, feathers expand downward to cover its nostrils, slowing the cold air and giving it a chance to warm up before it is inhaled by the grouse.
Every fall ruffed grouse grow skin-like fringes called pectinations on either side of each toe. They serve as snowshoes, helping grouse stay on top of the snow when walking, and also help them cling to icy branches while eating the buds of poplars and other trees in the winter. In the spring grouse shed these adaptive fringes. The bird whose foot is in this photograph met its untimely death about a week ago (they frequently fly into windows, as this one did), and I was curious to see the stage of development of the pectinations at this time of year. They appear to be about half to two-thirds the size they will attain when fully developed.