Different bird behaviors explained

Many of us enjoy watching birds and their behavior. Trying to decipher which individuals and species are dominant at a feeder can provide hours of entertainment. If you watch birds, you have a very real chance of seeing something no one has ever seen before!

Behavioral observation data can be extremely valuable for scientists. As explained in this blog post, observations like these can help scientists understand what shapes species distributions and why certain species are expanding their ranges while other ranges are shrinking. Yet, unlike standard FeederWatch counts (which and how many birds were present), behavior can be interpreted differently by different observers. For instance, we might all agree that both a chickadee and a titmouse were present at a bird feeder, but we might not agree that the chickadee seemed frightened by the titmouse. To minimize differences in interpretation, we are carefully restricting the behaviors users can record to two that can be defined easily: displacement and predation. Also, in light of a number of recent questions that have come in from users, we are going to be adding some additional details here to clarify how these behaviors are different from one another.

Displacement behavior

Displacement is when one bird actively takes over the position of another bird. By actively, we mean the dominant species is interested in taking over a resource (usually food, but sometimes even a preferred perch) occupied by the subordinate bird, and it displaces that species to do so. This is distinct from an attempted predation event, when the smaller bird flies away to escape the larger. And it is distinct from a mobbing event, when the aggressive species mobs the target species for reasons unrelated to resources (for instance, when a potential prey species mobs a predator to encourage it to leave the area). For the purposes of this project, we are only interested in clear-cut examples of displacement, such as when one bird flies or hops towards another and the subordinate bird vacates its position in a clear case of deference towards the dominant bird. Sometimes birds, particularly species like Blue Jays and Red-bellied Woodpeckers, can arrive suddenly at a feeder, causing the birds there to scatter momentarily. Such instances are more difficult to interpret, so please only submit clear examples of when one bird actively displaces another. Here are some example videos of displacement behavior.

House Finch displaces Lesser Goldfinch

Tufted Titmouse displaces Black-capped Chickadee

This All About Birds blog post also discusses the behavior, with some additional example videos. Displacement includes cases where a dominant bird physically knocks a subordinate bird off a perch–some users will know this often happens between hummingbirds and other aggressive nectarivorous birds. For our purposes, displacement does not include cases where a subordinate bird acts submissive towards a dominant bird or where a subordinate bird leaves before a dominant bird arrives. While these are certainly behaviors that do happen, they are much more difficult to interpret. For now we are only interested in the most clear-cut cases—one bird actively displacing another.

Occasionally you may see an unsuccessful displacement event: when the source bird clearly attempts to aggressively chase off the target but the target holds its ground. Don’t worry—we have a category for this behavior. Enter this observation as “Displaced,” but click the Unsuccessful button next to it.

Predation behavior

Predation events between birds are rarely seen. Although they can be upsetting to see, statistically speaking, you are very lucky if you see one, and we want to know about it if it occurs in your count site during a FeederWatch count! Unsuccessful attacks, such as a Cooper’s Hawk flying at a bird feeder and coming up empty, are also very interesting and provide some indication of what the hawk is interested in eating. Due to the speed with which these events typically happen, it may not be possible to identify both species. Only record observations where you are certain about the identity of both species. If the predation attempt is unsuccessful, then click the box to indicate that when you report the event.

A note about terms: the verb predate means to come before. Therefore, we use the verb depredate to describe the behavior seen in a predation event.

Do you have a video of a predation event? Contribute to the Macaulay Library today! In the meantime, here is a link to a video on YouTube: