IN 2002, THEN-EXECUTIVE DIRECTOR of Seattle Audubon Chris Peterson heard a short public-radio show called StarDate. “We could do that with birds,” she said to herself. In 2005 her thought became BirdNote, a two-minute, seven-day-a-week public-radio “interstitial” (as short programs are called) that—like all birds of a different feather always do—caught my ear. More recently, a lot of you commented on one of my bird stories by asking 150-plus questions, and I had an “aha” of my own: I’d ask BirdNote if they’d collaborate on answering them, in words and audio clips. The first in our series tackles the subject: How do birds make themselves at home—even in winter?
Ellen Blackstone of the BirdNote team (who describes her job there as “writes/edits/finds photos/posts to the website/sits in on recordings”—sort of like my job at A Way to Garden) was kind and patient enough to be our teacher. Remember, parts of each answer are in the 2-minute clips you can stream (all in the green links–or you can read the transcripts of each episode at those links if you prefer). Here we go:
nest, versus roost
Q. The topic of where birds prefer to live, and especially the role of the nest in their lifestyles, seemed to provoke my readers’ curiosity—and also probably some misconceptions. What’s “home” to a bird?
A. The great number of migratory species are all away from their nests–some as far as a different continent–during the nonbreeding season. Even among the residents, the majority of birds do not use their nest as a home but only a place to raise their young.
Exceptions would be some hole-nesters that roost in their cavities throughout the year, but they are a real minority. Those might be chickadees or their cousins, the titmice, or perhaps nuthatches or small woodpeckers.
There is a distinction between nesting and roosting. What most birds do at night is roost: they find a safe place to sleep, and enter it secretively so that predators don’t suspect. Individuals of some species roost alone, others do so in groups. (Listen to the difference in this BirdNote episode.)
Many birds nest in habitats different from where they spend the rest of the year…for instance:
- Great Blue Herons nest in trees! (The audio scoop on that.) (Heron photo at top of page, copyright Tom Grey.)
- Willets, a type of shorebird, breed in prairie wetlands, but spend the winter along Pacific coastal shorelines from Washington State south all the way through Central America. (Stream the short story.)
- And American Crows, territorial during nesting season, gather in huge roosts for the night, during the winter. (Listen.)
baby, it’s cold outside
Q. Speaking of the comforts of home…how do birds stay warm in winter’s cold?
A. Their keys to success are varied, some built-in and others tactical:
- Many birds roost together. (The podcast on keeping cozy that way.)
- Down helps. Even a single small bird such as a wren or sparrow may have 7,000 to 10,000 feathers. (Hear how feathers insulate.)
- Birds’ feet have a special adaptation called Rete mirabile, Latin for “wonderful net.” (Because of it, feet don’t freeze.)
Talk about cold-proofing: These chickadees wedge themselves into tiny cavities and drop their body temperature 18 degrees!
Ptarmigans burrow into powder snow. Anna’s hummingbirds may spend the winter as far north as British Columbia. When it’s especially cold, they go into a state of torpor, conserving body heat and energy.
next week’s questions, and how to get birdnote
NEXT WEEK’S ANSWERS from among the most popular of 150-plus questions you asked me recently will be about birds on the move—the miracles of hummingbird migration, and when birds fly en masse, and why.
Meantime, listen to BirdNote’s latest podcast anytime on the player below, or by visiting their website. Subscribe to the podcast or RSS, free. More than 100 public radio stations playing BirdNote are listed here; if you like what you hear, why not ask your local station why they don’t have it, too.