Field Notes Friday: Mobbing chickadees
This week Jason Berard, Vice President of Stewardship, was out in the woods when he ran into a 'mob' of chickadees! As you can hear in the video, a flock of chickadees are gathering near where Jason was standing and using their classic 'chick-a-dee-dee-dee' warning call. But this very distinctive call is way more than just an alarm call.
When a chickadee spots a bird of prey (any hawks, owls, or falcons) flying nearby, they will let out one high pitched call. But if the hawk is perched on a branch nearby, they will use a loud, wide spectrum chick-a-dee-dee-dee alarm call to recruit other chickadees, to harass the predator. As the chickadees gather, they will alter the mobbing call depending on the size and threat presented by the predator to warn other birds nearby. Most typically they change the dee dee dee note at the end of the call, sometimes adding five, 10 or 15 dees. However, there are a number of other ways chickadees alter the call that humans cannot hear.