Question: The American Robins recently have arrived in flocks to my yard. At the same time, Cedar Waxwings also came in mass. All summer, I saw only occasional Blue Jays but their color is now interspersed with the Robins and Waxwings. Why are these birds normally seen individually or not at all and suddenly they are here at the same time? Submitted by Judy Morr

It is not uncommon to see different species of birds flocking together in the fall and winter. At this time winter birds work together to find food that is sparse compared to the abundance available during the warmer months. The more eyes, the better for locating food sources. Recently, during one of the Early Morning Bird Walks at Caw Caw we noticed Cedar Waxwings and American Robins together in trees feeding on berries.

These two species are apparently common traveling partners in the fall and winter. Dozens of birds would fly up in mass to the next tree that looked promising for a better feed. There is no competing when there is a bounty of berries. It is interesting that Cedar Waxwings are social birds year round whereas American Robins know the benefits of grouping together during the cooler months, but become territorial in the spring during nesting season. For more information check out Robins and Waxwings in Winter and Summer Comparing Behaviors. Agricultural fields, which are abundant around John’s Island, are another area that you might see mixed flocks feeding on grain and seeds remaining after the harvest.
A single bird in a flock is also safer because there are many other birds to look out for predators, such as hawks or owls, as he eats or rests. A hawk cannot easily pick off a single bird crowded with others as they perch on power lines or in trees. I’m sure most people have noticed a hawk being chased away by a swarm of smaller birds. Interestingly you may also see a couple of Blue Jays together with Robins on a lawn during winter months. Blue Jays may raid a Robin’s nest for eggs or hatchlings during nesting season, but are more interested in acorns, seeds, and insects in fall and winter and are excellent alarms for incoming predators.
Frigid nights will also bring birds together. A tight knit flock roosting in trees at night offers a greater defense from the cold winter weather. BirdNote, a wonderful short daily podcast, recently released 61 Tons of Robins! about how many American Robins were counted in Florida roosting together at night.
So, it appears that birds engage in activities that are beneficial to their survival. Large numbers of birds and even different species will flock together in fall and winter when they are more vulnerable to the elements in order to locate food, keep warm, and stave off predators.
Submitted by: Joleen Ardaiolo
Photos by: Ed Konrad