Posted by Beth Anne Quinlan, PhD Avian Sciences on 2/29/2020 to Wild Birds
Over the weekend, my husband and I were sipping our coffee on our back porch while looking into the yard and enjoying all that nature had to offer that morning. Our yard, and both of our neighbors, was filled with dozens of American robins searching for food. It reminded us of the starlings that would group in our yard in Ohio each fall. So Tim asked, “Given that we have robins year-round, why are they exhibiting migration-like behavior? Robins don’t migrate, do they?” Great question!
Migration Patterns in Birds
There are a number of avian migration patterns – continuous, periodic (such as annual migrations), and one-way (typical of juveniles). Cyclic migrations include birds living in one habitat and heading to and from feeding areas daily, those that migrate annually, and those that migrate back and forth for a change of range. To make this more complex, not all species have a complete migration—several have partial migrations (some migrate while others stay put) and others (such as Juncos) have differential migration, where some members of the population travel different distances than others (in the case of the Juncos, the females and young go farther).
Migration in Robins
So what about the robins? American robins have partial migrations. So, some stay put while others head south during the winter. Robins migrate in response to food availability rather than temperature. When wintering in cold climates, they dine on fruit and move about as food sources become depleted. As the temperature warms to above 37 F, insects and worms become available and American robins take advantage of these preferred food sources.
Is Spring Here?
My mother used to say that she knew it was spring because she saw the first robin of spring. We lived in Northern Michigan at that time, an area where robins are only seen during their breeding season. If you live in the USA and not near the Canadian border, how can you tell that spring is here and the robins you see have arrived at their breeding territory? By their song. American robins sing upon arrival at their breeding territory.
Want to enjoy birds year-round without them leaving you for a better food source? Consider adding a bird figurine or hanging bird to your home—they add the joy of birds and won’t leave you for a better food source.