May/June 2023

The circumpolar willow grouse is the most widespread of all grouse. In subarctic Fennoscandia they feed on twigs from birch bushes in winter. Only the bark is digested. A recent study showed that grouse selected short twigs with rings of thick bark and the thinner parts of twigs with smooth and thin bark. The intake of undigestible wood is thereby minimized. This male willow grouse in its spring nuptial dress with white body, brown neck, and brilliantly red eyebrows was spotted one early April morning at Håkøya outside Tromsø, Norway, by setter dog Mackie and photographed by his master, Jon Aars. Full open access paper here.

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