While folks in many places are still waiting for robins, others are already watching their robins. That means eating berries and crabapples instead of worms. Sometimes when the weather gets really cold, birds on territory have to retreat to their winter behaviors for a few days. Robins are common backyard birds throughout most of North America, so you'd think their migration would be easy to understand. But it's actually pretty complicated.
Male robins arrive anywhere from a few days to several weeks before females.
Males must eat enough to remain strong and reach the nesting areas early enough to declare and defend the best territories, and to attract females. Females must arrive healthy enough to lay eggs and raise the young of the next generation. Birds who head north too early may find cold weather and poor food supplies. The females are a bit paler and drabber in color, but otherwise look quite a bit like the males, so it takes some practice for us to tell them apart. A pair of robins needs several things in their environment before they'll start nesting.