Watch as robins pick the Winterberry Holly berries in Paoli, PA. The birds have since eaten all the fruit.
The behavior in this video may be a sign that a cold winter is on its way. As temperatures cool, robins adjust their diets. They consume the berries that are available rather than protein-rich worms that they access when the ground is soft. Since the birds are less active during the winter, the carbohydrates and nutrients in the berries are enough to sustain them.
Male robins’ main task is to find and defend a territory, while females focus on laying eggs. Well-nourished females have an easier time with reproduction, so female robins are more likely than males to follow food sources south.
Soon, the robins will leave Chester County, taking the mild weather with them. We can look forward to their return in spring.