While Ruffed Grouse are plentiful throughout most of New England, one has to go to northern Vermont, New Hampshire or Maine to see its cousin, the Spruce Grouse. Associated with boreal forests, this largely herbivorous bird feeds primarily on the needles of pine, spruce and fir (a small amount of animal matter is consumed in the summer as well as ground vegetation). Especially in the winter, a large volume of conifer browse is consumed in order to meet energy demands.
The grouse holds the needle between the tips of its mandibles and breaks it off by flicking its head. This action, and the fact that Spruce Grouse feed exclusively on needles in the winter, leads to the wearing off of the tip of the bird’s upper mandible by spring.
If you are searching for a Spruce Grouse, you might want to concentrate in the middle of the crowns of trees, as this is where the birds tend to forage. Theories for this preference include the fact that needles in this location have higher nutritive value, branches provide sturdy support, and grouse can see approaching avian predators while remaining partially concealed. (Birds of North America, Cornell Lab of Ornithology). (Photo: male Spruce Grouse browsing on Tamarack needles and (inset) looking for grit on the ground.)
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