Connecticut warbler in western PA, September 2013 (photo by Steve Gosser)
Connecticut warblers are rarely seen on migration and it's not just because they skulk in dense underbrush. A study published last May in Ecology shows they have a very unusual migration route.
McKinnon, Arturo and Love attached geolocators to 29 male Connecticut warblers in Manitoba in 2015, then recaptured four of them the following spring when they returned to breed. The data from the geolocators shows the four birds followed similar routes to their wintering grounds in South America.
After flying east to the Atlantic coast with stopovers along the way each bird launched out over the open ocean and flew two days non-stop to the Greater Antilles, probably Haiti. After refueling in the Caribbean they flew again over the ocean to South America and the Amazon basin.
To give you an idea of this feat I drew a very rough map based on my reading of the study. This map is not the real thing! Click on the image to see one of the actual maps or here for all four.
My own rough drawing of the warblers' route. CLICK on this IMAGE to see the real maps.
With two long flights over open water, no wonder we don't see many Connecticut warblers in migration.
If you're really lucky you might see one this month in Pennsylvania. Otherwise you'll have to wait until next year.
Blackpoll warbler, Sept 2012 (photo by Marcy Cunkelman)
As warblers migrate through Pennsylvania we find them feeding together in mixed flocks during the day. Does that mean they were traveling together overnight? Maybe not. Warblers often have very different breeding and wintering destinations, making it hard to coordinate their trips.
Here are two extreme examples. Blackpoll and pine warblers look similar but you can't find two more different migration strategies. Their breeding and wintering grounds are as far apart as it gets.
The blackpoll warbler, above, is a long distance champion who travels 7,000 miles from his breeding grounds in North America's boreal spruce and fir forests to wintering grounds in South America. To shorten the trip some of them fly non-stop over the Atlantic Ocean for 88 hours to reach South America's shore.
The pine warbler, below, never travels that far. His breeding and winter ranges are completely contained within North America from southern Canada to Florida and he's found year-round in the southern U.S. Pine warblers breed in parts of Pennsylvania.
Pine warbler (photo by Anthony Bruno)
The maps below -- blackpoll (left), pine warbler (right) -- tell the story in three colors: Yellow is breeding range, Blue is wintering range, Green is year-round.
Range maps for blackpoll and pine warblers (maps from Wikimedia Commons). Colors are: yellow=breeding, blue=wintering, green=year-round
As you can see, blackpolls leapfrog over the pine warbler's range.
Though I saw blackpoll and pine warblers in a mixed flock in Perry County last weekend, they probably weren't traveling together.
(photo of blackpoll warbler by Marcy Cunkelman; pine warbler by Anthony Bruno; maps from Wikimedia Commons: blackpoll and pine)
This month chimney swifts (Chaetura pelagica) are migrating to South America, leaving before the weather's too cold for the flying insects they eat on the wing.
At dusk the flocks swirl around large chimneys then dive in to roost. This video from New Glasgow, Nova Scotia shows them streaming into an old schoolhouse chimney. Wow!
Don't worry when you see smoke coming out of the chimney at the end of the video. An observer explains: "There are actually two flues in the chimney. The chimney swifts use the larger flue, while the smoke is vented from the smaller flue, so the birds are safe. In fact, they probably benefit from the bit of heat that comes from the smaller flue."
Stake out a chimney in town to enjoy the air show or monitor a wooden chimney swift tower near you.
Dickcissel singing in western PA, June 2017 (photo by Anthony Bruno)
While I was on vacation in Europe I missed the chance to report on an unusual bird in Pennsylvania this summer.
First seen in early June, dickcissels (Spiza americana) have now been reported in 14 of Pennsylvania's 67 counties, north, south, east and west.
Their sudden appearance in the middle of the nesting season is a tribute to their peripatetic lives. If nesting fails at their preferred location they'll travel a thousand miles to find a better nesting site.
Perhaps they came to Pennsylvania this year because there's a severe drought where they usually nest in the plains of North and South Dakota and Montana. Bob Mulvihill wrote about this correlation during the dickcissel invasion of 1988 (click here and scroll to page 6).
U.S. Drought Monitor map, 4 July 2017 (map from U.S. DroughtMonitor, UNL, USDA, NOAA)
Least flycatcher, near Point Pelee, Ontario (photo from Wikimedia Commons)
Bird migration continues in western Pennsylvania. Here's what's on tap this week.
Flycatchers wait until warm weather brings out the flying insects so we should expect them soon. On Wednesday it'll be 90 degrees!
Watch and listen for Empidonax flycatchers: least, acadian, willow and alder. All of them are small, drab olive birds with wing bars. They look alike but you can tell them apart by voice. Included below are summary descriptions from Cornell's All About Birds.
Pictured above is the least flycatcher (Empidonax minimus), the smallest of the four. All About Birds calls him "a small drab flycatcher of open woods." He sings, "Che-BEK"
The acadian flycatcher (Empidonax virescens) looks like the least flycatcher but he's larger and greener. Find him along streams and in deciduous forests. His voice is an explosive "PEET sah!"
The willow flycatcher (Empidonax trailii) prefers wet brushy sites and sings "fitz-bew." On Sunday I checked for willow flycatchers at one of their favorite sites, the Duck Hollow end of Frick Park's Nine Mile Run Trail. They hadn't arrived yet.
And finally, the alder flycatcher (Empidonax alnorum) is so similar to the willow flycatcher that they used to be the same species. The only way to tell them apart is by voice. All About Birds describes the alder's song as "a harsh, ripping "f-bee-oo." Good luck!
We'll also see some "eye candy" this week. Here are two warblers to watch for.
Mourning warbler, Forest County, PA, 13 May 2017 (photo by Anthony Bruno)
This mourning warbler (Geothlypis philadelphia) was already in Forest County, Pennsylvania when Tony Bruno photographed him last weekend. Mourning warblers prefer to skulk in dense vegetation so you'll hear them before you see them.
Blackpoll warbler gleaning insects from a boxelder (photo by Chuck Tague)
Blackpoll warblers (Setophaga striata) could be confused with black-and-white warblers but they have solid black caps and solid white faces. No stripes there! Blackpolls sing a high pulsing song which All About Birds calls nature's hearing test. I've included the sonogram below so you can see when it plays. Can you hear it? I can't any more. (There's a Swainson's thrush in the background of this recording.)
(photo credits:
least flycatcher from Wikimedia Commons; click on the image to see the original
mourning warbler by Anthony Bruno
blackpoll warbler by Chuck Tague)
Last weekend's rain and north winds may have slowed down migration but the birds have to get here eventually. Here are five of the many species to look for thanks to Birdcast's Upper Midwest and Northeast forecast.
A few red-eyed vireos (Vireo olivaceus) are already here but the bulk of them are arriving this week. Warbler-sized with plain olive backs and white chests, their distinguishing feature is a charcoal eye line. They do have red eyes, as shown in Shawn Collins' photo above, but it's unlikely you'll see this because vireos are usually high among the leaves. Listen for their relentless song, "Here I am. Where are you? Here I am. Where are you?"
"Red-eyed Vireo (Vireo olivaceus)" from xeno-canto by Ross Gallardy. Genre: Vireonidae.
Black-billed cuckoos (Coccyzus erythropthalmus) nest in contiguous forest but you might find one anywhere on migration. I saw one in Schenley Park last week. About the size of a robin with a very long tail, they have plain taupe backs, plain white chests and black bills that set them apart from their yellow-billed cousins. Black-billed cuckoos have red eyes, too, but you'll have to be as close as Steve Gosser's photo if you want to see them.
Black-billed cuckoo (photo by Steve Gosser)
How will you find a black-billed cuckoo? They often sit silently among the leaves but they move like no other bird. Perched in a hunched position they jump from branch to branch with awkward flapping as they search for caterpillars. If they were as large as the squirrel cuckoo of Central and South America, you'd say they move like squirrels. Here's the black-billed cuckoo's song:
"Black-billed Cuckoo (Coccyzus erythropthalmus)" from xeno-canto by Andrew Spencer. Genre: Cuculidae.
At last we'll see a shorebird that's easy to identify! Dunlin (Calidris alpina) are due here this week. Most of the time dunlin are so plain that you have to identify them by size, shape and habits but in May they stand out as the only small rusty-backed shorebird with a black patch on its belly.
Dunlin in breeding plumage (photo from Wikimedia Commons)
Watch for bay-breasted warblers (Setophaga castanea) or you'll miss them! They nest in Canada so they're only here for a few weeks in May. With dark backs, black faces, cream-colored necks and a splash of rusty-red bay on their throats and sides these birds are truly "eye candy." Their song is so high-pitched that it's almost beyond my audio range. Click here to hear.
Bay-breasted Warbler (photo by Chuck Tague)
Canada warblers (Cardellina canadensis) are arriving, too, but you'll have a longer chance to see them. As their name suggests they nest in Canada but they also breed in the forests of northern Pennsylvania and the Laurel Highlands. Look for their charcoal gray backs, yellow throats and bellies, and black necklaces. Unlike magnolia warblers they have no white accents. Their song says, "Chip chuppety, swee ditchety." Click here to hear.
Canada Warbler (photo by Cris Hamilton)
The birds will be hard to see now because the trees have so many leaves ... but leaves attract bugs and that's why the birds are here.
The Big Push of migration is here! I've already seen some gorgeous birds that are due this week and there's more to come. Here's what we can look forward to.
Scarlet tanagers (Piranga olivacea) were already at Enlow Fork in Greene County, Pennsylvania on Friday. When they get here, listen for two sounds that tell you this bird is nearby: the Chip-burr call and the male's "robin with a sore throat" song.
American redstarts (Setophaga ruticilla) were everywhere at Enlow. Their song can be hard to identify so look for the flash of the male's black, white and orange colors at mid height in the trees.
American redstart, May 2011 (photo by Steve Gosser)
Schenley Park's Panther Hollow Lake has a concrete border so I was surprised to find a solitary sandpiper (Tringa solitaria) feeding there on Saturday morning, 29 April. Look for these dark-backed sandpipers with white eye rings along the water's edge. They travel alone.
Solitary sandpiper, May 2011 (photo by Steve Gosser)
And here are two species that I haven't seen yet. According to Birdcast, they'll arrive this week.
The magnolia warbler (Setophaga magnolia) is a tiny bird with a yellow throat and belly that's accented by a black necklace. He has white splashes on his head, wings and tail that distinguish him from the Canada warbler. Here's his song.
Magnolia warbler (photo by Steve Gosser)
Swainson's thrushes (Catharus ustulatus) are probably the most numerous thrush in North America but we only see them on migration in Pittsburgh. Look for the buffy lores and eye ring and listen for their wiry upward spiraling song.
Swainson's thrush (photo by Steve Gosser)
Bird migration is in full force in western Pennsylvania. It's going to be a great week for birds!
Years ago Chuck Tague taught me that gray catbirds (Dumetella carolinensis) are a special signal during spring migration.
Catbirds spend the winter in Florida, Cuba and Central America, then return in the spring after the first tantalizing migrants (the blue-gray gnatcatchers and Louisiana waterthrushes) but before the big push of warblers, thrushes and tanagers.
Because they're the leading edge of the best part of migration, Chuck always announced his first gray catbird of the year. I'll carry on his tradition.
Yesterday was the day! On 28 April I saw my first gray catbirds of 2017 at Enlow Fork in Greene County and at home in the City of Pittsburgh.
This year the catbirds did not arrive alone. At Enlow Fork we also saw rose-breasted grosbeaks, scarlet tanagers, Baltimore orioles, wood thrushes, northern parulas, American redstarts, common yellowthroats and more.
I'm still waiting for an indigo bunting. Maybe today ... 🙂
p.s. Many of us learned a lot from Chuck Tague who passed away last June. This coming Thursday, May 4 at 7:30pm the Wissahickon Nature Club will hold an All Members Night A Tribute to Chuck Tague. Bring up to 12 slides or digital photos to share. Click here and scroll down for location and meeting information.
Chimney swifts (Chaetura pelagica) are due this week. We're likely to hear their chittering sound before we see them hawking insects overhead. Though they look like cigars with wings (above) they're actually related to hummingbirds! In the western U.S. watch for the similar Vaux's swift (Chaetura vauxi).
Two of this week's predicted migrants were in Schenley Park yesterday.
A blue headed vireo (Vireo solitarius) sang his slurred, sweet song next to Bartlett Playground (click here to hear). Bobby Greene's photo shows off this vireo's blue-gray head, white spectacles, and the yellow-green wash on his flanks that makes him hard to see among new leaves.
Warbler season is here with yellow-rumped warblers back in town and one or two sightings of black-throated green, prairie, yellow, black-and-white and a common yellowthroat in our area.
Ruby-crowned kinglets (above) are tiny hyperactive birds with a song that sounds like a carolina wren + winter wren tossed with a chatterbox. Click here to hear.
The blue-gray gnatcatcher (Polioptila caerulea) is another tiny hyperactive bird who's often heard before he's seen because of his unique "bizzy" sound. Listen for this call and watch for the small bird pictured below.
Blue-gray gnatcatcher (photo by Steve Gosser)
Northern rough-winged, tree, and barn swallows are all on the move. Click on their photos for identification tips and the calls of these species. Northern rough-winged swallows are easiest to identify by sound because they make a spitting noise.
Northern Rough-winged Swallow (photo by Chuck Tague)
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