Robins and Waxwings in Winter and Summer
Comparing Behaviors

Robins and Cedar Waxwings together
Photo: Christine Haines

Many observers see American robins and waxwings being very sociable to each other in winter. They don't look alike or sound alike, yet the two species are okay hanging out with each other. How are they alike and different?

A Tale of Two Species
American robins and waxwings are both flocking species in winter. That's because both eat fruit. Flocking is helpful because flocks have more eyes to discover new sources of fruit. Where they find fruit, it's abundant. Lots of fruit means flock members don't have to worry about competing.

Robins are very sociable in winter, though not quite as sociable as waxwings. Waxwings are the least territorial of all songbirds. They don't defend a nesting territory against their own species. Waxwings don't even defend a personal space. They often sit shoulder to shoulder when feeding on berries or flower petals. You can sometimes spot them passing a berry down a line of birds, each bird passing the berry to its neighbor before one bird suddenly swallows it (see more *below). Robins never pass food back and forth. Robins usually don't sit quite as close together as waxwings. Robins never sit shoulder to shoulder, even in trees.

As days grow longer and spring turns to summer, waxwings remain sociable. But robins slowly become more territorial. Some robins will start squabbling in the feeding flocks. Some robins will sing now and then. Little by little the robins' increased squabbling and singing will break up the robin flocks. In other words, the robins' switch to being territorial is what eventually breaks up their flocks.

Robins have a loud song. Their song helps warn away other robins. This is how they ensure a big territory for getting enough worms for their babies. Waxwings have a soft little snore (recordings courtesy Lang Elliot) because they don't need to warn each other away.

*A Theory on Waxwings' Berry-Passing Habit
Why do waxwings pass berries back and forth among themselves? Journey North robin expert Laura Erickson wondered until one winter when she was caring for an injured Bohemian Waxwing. A huge flock of Bohemian Waxwings were visiting her yard, feeding on mountain ash berries. Following their example, Laura fed some of these berries to her hurt bird. Ten or fifteen minutes later, out they came in the bird's poop, completely undigested! The waxy coatings of the berry were apparently too thick for the bird's stomach acids to dissolve during the short time the berries were in its stomach. So Laura picked some more berries. This time she rolled them in her fingers for a few minutes to soften them. Then she fed the softened berried to the waxwing. Voila! Now the bird could get the nutrition from the berries.

The charming food-passing habit of waxwings apparently serves two purposes: It helps to cement the bonds between these sociable flocking birds. It also helps them digest their food!

Try This! Journaling Question

  • How are robins and waxwings alike and different? Make a Venn diagram to sort out the facts you found on this page. How does each type of behavior benefit the species?

National Science Education Standards

  • An organism's behavior patterns are related to the nature of that organism's environment, including the kinds and number of other organisms present, the availability of food and resources, and the physical characteristics of the environment.
  • An organism's behavior evolves through adaptation to its environment. How a species moves, obtains food, reproduces, and responds to danger are based in the species' evolutionary history.