Birds that eat insects leave Pennsylvania for the winter but the omnivores, like this house sparrow, stay behind. Food won’t be a problem but it’s going to get cold so the house sparrows get ready in advance.
A study by Lowther and Cink in 1992 found that house sparrows (Passer domesticus) prepare for winter by molting into heavier plumage. Plumage weight increased 70% between August and September alone. Summer weight is 0.9 grams; winter weight is 1.5 grams.
In September the house sparrows put on their winter coats.
(photo from Wikimedia Commons; click on the caption to see the original. This article was inspired by page 153 of Ornithology by Frank B. Gill, 3rd edition.) )
By August in Pennsylvania, ruby-throated hummingbirds (Archilochus colubris) have finished breeding and all of them, young and old, are fattening up for their migration to Central America. Many are visiting backyard feeders.
Last week on PABIRDS Rob Blye posted a collection of interesting questions about feeding hummingbirds, including someone’s concern about sugar. Here’s a summary of the feeder discussion with embedded links to the original text.
Do young hummingbirds imprint on feeders as a preferential food source and ignore natural food sources?
No. Scott Weidensaul writes that as much as 40 percent of the hummingbirds’ diet is made up of insects and other small arthropods which they pursue while away from our feeders. There’s no need to worry that they’re getting an unbalanced diet.
Is sugar bad for hummingbirds?
Not at all. Sugar is bad for humans but fine for hummers. Scott Weidensaul writes: “Flower nectar and a white cane sugar/water mix are essentially identical sucrose fluids. Four parts water and one part white sugar neatly replicates what they’re getting from flowers. “
Can we offer a different sweetener than sugar? What about honey?
Absolutely not! Scott writes that “substitutions are dangerous. Organic/brown/turbinado sugar or molasses can pack fatally high levels of iron, to which hummers are exquisitely sensitive, while honey, once diluted, becomes a stew of dangerous bacteria and fungi.”
Is it OK to hang hummingbird feeders if you cannot clean them frequently?
No. Spoiled food is dangerous for hummingbirds and it spoils daily in 90 degree weather. Clean your feeders thoroughly and regularly. Empty, clean and refill daily when it’s 90 degrees. You can extend this to every few days when the high is 60. Click here for guidelines from Aududon.
Should we add something to the sugar-water to prevent spoilage?
No. Scott writes, “avoid new products that claim to deter spoilage. Hummingbird experts are deeply suspicious about the safety of such additives.”
How do you attract hummingbirds if you can’t clean your feeders that often?
Yesterday in Schenley Park I saw a scarlet tanager with blotches on his belly. He was starting to turn green.
Scarlet tanagers (Piranga olivacea) molt twice a year. In January through March they molt into breeding or “alternate” plumage while on their wintering grounds in South America. The females don’t change color but the males turn from green to scarlet. Young males often retain a bit of green (click here to see).
When the breeding season is over, they molt back to basic plumage in July through September. The males look blotchy at first but when they’re done they’re bright olive green with black wings as shown below. By then they’re on their way to South America.
(photo at top in August, Tim Lenz; photo below in Oct, Andy Reago & Chrissy McClarren)
I was lucky to see yesterday’s scarlet tanager because he hardly made a sound. Tanagers have stopped singing now that breeding is over. This one was singing very softly.
p.s. Did you know that female scarlet tanagers sing? According to All About Birds: “The female Scarlet Tanager sings a song similar to the male’s, but softer, shorter, and less harsh. She sings in answer to the male’s song and while she is gathering nesting material.”
This friendly, intrepid and intelligent bird is the size of an American robin — but much smarter. He won the Royal Canadian Geographical Society’s contest for National Bird but the Canadian government is reluctant to name a national bird, though they have a National Tree (the sugar maple).
More colorful than his black-capped and Carolina cousins the boreal chickadee lives only in the boreal forests of Canada and a few bordering areas of the U.S. He’s such a spruce forest specialist that he caches only spruce seeds.
Don’t expect to hear him sing. Unlike his southern cousins, he doesn’t have a whistled song. Here’s the closest he comes to it (Xeno Canto XC46492 by Andrew Spencer at Boot Cove Trail near Lubec, Maine):
The pine grosbeak lives in subarctic and boreal habitats in North America, Scandinavia and Siberia. I could have seen one in Finland last year if I’d been in the right place.
Pine grosbeaks have such a wide range that their voices vary geographically. The best Xeno Canto recordings are from Scandinavia and Alaska but Newfoundland’s sound different.
Pine grosbeaks feed their nestlings insects but otherwise eat buds, seeds and fruit. Their Latin scientific name describes them well: Pinicola (pine tree dweller) enucleator (removes the kernel (nucleus)).
The females are orange-ish instead of rosy.
(photos from Wikimedia Commons; click on the images to see the originals)
Northern cardinals (Cardinalis cardinalis) are common backyard birds that we often take for granted though their family life is interesting.
Bob Kroeger photographed cardinals nesting in his Cape Cod backyard in May and June. The slideshow lets us pause and see what they’re doing.
The male is very bright red: This is good news for the family. Studies have shown that males with bright red breasts and females with bright underwings show more parental care to their young.
He feeds his mate at the birdbath: The male’s job is to feed his mate from nest building through brooding (and perhaps beyond). This makes sense because male cardinals don’t have brood patches. The females build the nest, incubate the eggs and brood the young.
She’s eating away from the nest: It’s perfectly normal for the female to spend time away from the nest, even if there are eggs in it. During incubation, which lasts 11-13 days, the female spends 30% of daylight hours away from the nest.
Two juveniles on a branch with their father: This cardinal couple beat the odds. The majority of nests fail due to predation.
How to recognize juvenile cardinals: The juveniles resemble their mother but their beaks are dark. (Adults have orange-red beaks.) The juveniles’ beaks will turn orange-red when they are 65-80 days old.
You can’t see the food in the father’s beak: The parents feed insects to their young but they carry the food far back in their large beaks. Researchers probably find this frustrating when they have to identify what the young are eating.
How long will the young depend on their parents? Juvenile cardinals are completely dependent on their parents for about 19 days. Around that time, their mother starts to build her next nest. Dad may feed the youngsters occasionally until they are 25-56 days old.
Next week the last survey window opens for counting nightjars by the light of the moon. It’s a fun way to go birding on a moonlit night — June 20 to July 6, 2018.
Nightjars are a worldwide family of nocturnal/crepuscular birds that eat flying insects on the wing. They have long wings, short legs, short bills and very wide mouths. Two of these cryptically-colored species are found in Pennsylvania:
Common nighthawk (Chordeiles minor), in flight above, breeds in cities and open habitat, grasslands, dunes.
Nightjar surveys are easy to perform and will not take more than two hours to complete. Volunteers conduct roadside counts at night, on scheduled bright moonlit nights, by driving and stopping at 10 points along a predetermined 9-mile route. At each point, the observer counts all Nightjars seen or heard during a 6-minute period.
We don’t think of swallows as songbirds but indeed they do sing. Our largest swallow, the purple martin (Progne subis), has a unique sound that carries far. With practice, you can recognize their voices even when you can’t see them.
Purple martins nest communally so the best place to learn their song is near a purple martin colony.
In early summer near their nests, you’ll hear songs, creaky rattles and the sound of begging juveniles. (Purple martins vocalizing near their nest, including begging calls of young, from Xeno Canto XC139568 by Russ Wigh)
The throaty, gurgling chirps are unique to purple martins. When you hear it overhead, look for a nearby colony and go see the swallows sing.
This is the Biggest Week in American Birding in northwestern Ohio and I’m not going to miss it. I expect to see my favorite warbler, the Blackburnian (Setophaga fusca) above, and up to five warblers whose names are out of place in Ohio.
The birds listed below were named for the location where a scientist first described them though they were on migration at the time. The name tells you more about the ornithologist’s travel schedule than it does about the bird.
“Described by Alexander Wilson in 1811 from a migrant specimen on the banks of Tennessee’s Cumberland River, its common name belies the fact that its breeding range is restricted almost entirely to the boreal forest zone of Canada, southeastern Alaska and the extreme northern fringe of the U.S.”
Alexander Wilson first described this species in 1812 and named it after the state of Connecticut, where he collected the first specimen, a fall migrant. The common name is something of a misnomer, however, because the species does not breed in Connecticut, nor is it a common migrant there.
This week brought in five more beauties, illustrated in photos by Tony Bruno and Steve Gosser. I saw most of them at Enlow Fork (SGL 302), just 45 air miles south of Pittsburgh. I’m sure they’ll be in town this weekend.
American redstart (Setophaga ruticilla), at top. Black, white and orange, as soon as the redstarts arrive they’re easy to find because they’re hyperactive and just above eye level. We saw 10 of them at Enlow Fork yesterday, April 26.
Northern parula (Setophaga americana), below. Smaller and slower moving than a redstart, parulas are usually in the tops of the trees, especially sycamores. We were lucky to see one at eye level at Enlow Fork.
Palm warbler (Setophaga palmarum), below: This warbler is easier to identify that you’d think because he pumps his tail and is willing to walk on the ground. I found him on the grass at Frick Park.
Black-throated green warbler (Setophaga virens), below. Usually found at mid-height in the trees, he sometimes hovers like a redstart to glean insects from the leaves. Enlow Fork.
Common yellowthroat (Geothlypis trichas), below: This one like to hide in thick bushes so we heard him before we saw him — and then just caught a glimpse. “Witchity, Witchity, Witchity” at Enlow Fork.
There are plenty of opportunities to see warblers this Sunday April 29. Click the links for details: