What Does the Rock Ptarmigan Eat?
The rock ptarmigan, known scientifically as _Lagopus muta, _has an omnivorous diet that changes depending on the time of year and location of the bird.
Between late autumn and early spring, the rock ptarmigan feeds almost solely on plants. The most common source of food for this bird is the catkins and buds from dwarf birch trees, or, in some cases, willows. Rock ptarmigans located in the Aleutian islands do not have access to birch trees, however, and they instead eat the tips off of the abundant crowberry plants that grow there.
In April, the diet of the rock ptarmigan begins to change. Overwintered berries from various plants become incorporated into their diet, alongside their usual winter diet of buds and catkins.
The biggest change in a rock ptarmigan’s diet occurs during the warm month of May. The ripe red fruit of the bearberry is a favorite of many rock ptarmigans. Some other plants they enjoy include lousewort and mountain avens. As snows begin to melt, spiders and insects begin to explore the terrain, a delicacy that is high in protein for the rock ptarmigan.
Rock ptarmigans enjoy the abundance of food in summer, but they live so far north that this summer is short-lived. The middle of August is when the rich foliage of summer begins to die off, and rock ptarmigans must change their diet once again. They eat seeds and berries until it is once again late October, when they return to feasting on the buds and catkins of dwarf birch and willow trees.
Young chicks feed almost exclusively on insects, including spiders and snails. After just a day of hatching, rock ptarmigan chicks are capable of leaving the nest, and they feed independently.
The rock ptarmigan has a foraging feeding style where it quickly pecks at nearby vegetation and uses its small, sharp beak to nip off leaves, berries, and seeds. A common winter tactic used by rock ptarmigans is to follow caribou or musk-ox herds. After the large animals have scratched away the snow, the rock ptarmigans can dig at the earth for food.
Flocks of rock ptarmigans feed together during the winter, an activity that takes up much of their time. Because rock ptarmigans need to consume roughly between one-tenth and one-fifth of their body weight every day, they spend nearly all of their day searching for food.
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