In the column Since You Asked in every issue of BirdWatching, Contributing Editor Julie Craves answers readers’ questions about birds and bird behavior. Here are two questions from our June 2017 issue.
While I was monitoring my Purple Martin house, I observed a fledgling exit the house, flying poorly, and closely followed by an adult male. When it appeared the young bird would fall, the male sped up and was able to carry the fledgling on its back for about 20 feet, after which the chick flew off by itself. Do other swallows exhibit this behavior? — Jim McKay, Calgary, Alberta
As martin landlords know, an encouraging parent, often the male, accompanies the maiden flights of youngsters. The adult will fly near the fledgling, spurring it to stay airborne, leading it to a safe spot, and protecting it from predators or harassment. Carrying a fledgling on its back is not a typical behavior for martins or other swallows. I believe you witnessed a highly serendipitous — and likely unintended — performance.
Why do birds destroy old squirrel nests? We have seen starlings tear apart these leaf nests several times. — Val and Johann O’Brien, Ann Arbor, Michigan
Although nests in cavities are often preferred, most tree squirrels will also build multiple leaf nests in the branches of trees. The nests are also known as dreys. A main nest might be used for raising young and is typically located in part of the territory where food is plentiful. Satellite nests scattered throughout a territory can be used as shelter from predators when a squirrel is out and about or to cache extra food stores. The stashes of seeds and nuts provide a bonanza for birds that discover them. I expect that birds such as Blue Jays and starlings can quickly learn that squirrel nests may contain such a stockpile. Squirrel nests can also harbor many other food items such as spiders, moths, beetles, and other insects and invertebrates. I often see smaller birds like Carolina Wrens rummaging in squirrel nests, and I suspect it is these types of food items they are after.
About Julie Craves
Julie is supervisor of avian research at the Rouge River Bird Observatory at the University of Michigan Dearborn and a research associate at the university’s Environmental Interpretive Center. She writes about her research on the blog Net Results, and she maintains the website Coffee & Conservation, a thorough resource on where coffee comes from and its impact on wild birds.
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