Category Archives: Migration

Migration By Smell

Gray catbird (photo by Shawn Collins)

I have not seen a gray catbird in Pittsburgh yet but I know they’re on their way. Next month they’ll arrive from their wintering grounds in the southern U.S., the Caribbean and Central America. How do they get here?

Migratory birds are born with an innate sense of direction and distance to their goal but must learn how to get there on their first trip south. After they’ve made the trip once, they create a mental map and can use the sun, stars, earth’s magnetic field and their sense of smell to return home.

Their sense of smell? Yes! Birds do have a sense of smell and they use it.

On Throw Back Thursday, learn how gray catbirds proved they navigate by smell in: Sniffing Their Way North.

(photo by Shawn Collins)

Winter Crows Will Soon Be Gone

Crows burst off a building as they prepare to roost in Oakland, 4 Nov 2016 (photo by Kate St.John)
Crows burst off a building as they prepare to roost in Oakland, 4 Nov 2016 (photo by Kate St.John)

There’s one thing we can count on with the coming of spring. Pittsburgh’s winter crows will soon be gone.

Every year thousands of crows come to town in November, build to a crescendo by the end of the year and disperse in late February through March.

Residents near the corner of Bellefield and Bayard Avenues in Oakland can hardly wait. This winter a nightly flock of 3,000 to 4,000 crows plagued their area, roosting in trees near the Western Pennsylvania School for Blind Children. The scene in North Oakland looked a lot like this 2013 video from Minneapolis.

The video’s author, Chuck Smith, points out that the crows usually don’t spend the night in his neighborhood but when they do they leave their calling cards behind.

I like watching crows but I don’t have to live with them.

(video by Chuck Smith on YouTube)

It’s A Wonder

Painted bunting in Allegheny County, 22 Jan 2020 (photo by Steve Gosser)

On Monday morning, 20 January 2020, a sparrow-sized songbird, colored like an exotic parrot, showed up at a backyard feeder in suburban Pittsburgh. It happened to choose the backyard of Brian Shema, Operations Director at Audubon Society of Western PA. His Rare Bird Alert immediately attracted a steady stream of birders to see this gorgeous visitor. (If you want to see the bird, instructions are at the bottom of this article.)

Painted buntings (Passerina ciris) are seed-eaters that breed in the coastal Southeast and south central U.S., and spend the winter in Florida, the Caribbean and Central America. Though one occasionally shows up in eastern Pennsylvania this individual is quite out of range in the western part of the state. He’s only the third Allegheny County record.

He’s also extra special because he’s male. Female painted buntings are nice to find but their green color is not so photogenic.

To highlight the male and female difference here’s another male, photographed in Florida by Chuck Tague in 2012. (The border emphasizes that this is not the Pittsburgh bird.)

Painted bunting, Florida, 2012 (photo by Chuck Tague)

Of course we all wonder where the bunting came from and hope for his continued success. So far, so good. He’s hanging out with juncos and successfully avoiding predators, including the merlin that watched Brian’s backyard on Thursday afternoon.

If you’d like to see him, go to this location pinpointed on eBird’s map. Make sure you stay on the street, don’t walk in anyone’s yard, and park without blocking anything. The house is on a corner lot so you can see the feeders from the street. He was there all day yesterday (Friday 24 Jan). Chances are very good that you’ll find other birders looking at him when you get there.

(photos by Steve Gosser, Wikimedia Commons and Chuck Tague; click on the captions to see the originals)

Bird Migration on Merchant Ships

This 9-minute video, filmed on merchant ships by Odysseas-Froilan Papageorgiou, provides a unique perspective on migratory birds.

Terrestrial birds that migrate over the ocean will land on ships to rest and refuel, especially during bad weather. Some birds are exhausted by the time they land. The ships attract insects that are eaten by songbirds. The songbirds attract birds of prey and shrikes.

The video showcases 70 species seen during Europe voyages. Each half of the video is in taxonomic order. My favorites were the birds of prey and a colorful bird that was new to me — the black-headed bunting. Don’t miss the hobby, the peregrine and the long-eared owl.

Best Bird is saved for the end!

(video by Odysseas Froilan on YouTube)

MOTUS Peregrines On The Move

Downtown Pittsburgh juvenile peregrines. Bird on left has a MOTUS tag, 20 June 2019 (photo by Lori Maggio)

In June 2019 the Pennsylvania Game Commission fitted 10 of the state’s fledgling peregrines with MOTUS tracking devices to study where they go and how many survive their first year of life. Five months later the network has data locations for three (or maybe five) of them.

Keep in mind that only a few data points have been captured, the MOTUS data is still preliminary, and false positives sometimes occur. That said, here’s what we know so far.

Harrisburg female, Red, 46/BS (ID# 24660)

The path of the Harrisburg female peregrine (Red, 46/BS, ID#24660) looks quite promising. She flew first to Nockamixon (19 Sept), then west and south to Lamb’s Knoll (2 Oct) and Newtowne Neck near Compton, Maryland (4 Oct). The enhanced map below includes her banding location in Harrisburg. Click here for her path on the Motus website which does not include her banding location.

Map of Harrisburg Red peregrine, ID#24660, enhanced from MOTUS tracking map

Harrisburg male, White, 22/BZ (ID# 24662)

Initial data on the Harrisburg male (White, 22/BZ, ID#24662) were clouded by inaccuracies that placed him in both Reading, PA (Drasher) and Saskatchewan, Canada — 1,600 miles away — on the same day.

After removing the Saskachewan error there was still one more puzzle. The data table indicates that Harrisburg White flew 766 miles four times — from western Ontario (Harrington) to the Bay of Fundy (Gardner Creek) and back again. Would a bird have done this? And could he have made one of those trips in a single day, 24-25 August, in a head wind? Hmmm! Doubtful.

screenshot of Harrisburg White data table as of 25 Nov 2019

With those questions in mind I created the enhanced map below, adding his banding location and removing Gardner Creek (which may still be on his MOTUS map here). While his data is under review Harrisburg White is still on the move. He showed up near Aurora, Ontario on 16 November.

Map of Harrisburg White peregrine, ID#24662, enhanced from MOTUS tracking map

Nazareth, female, Red, 20/CA (ID# 24665)

Hatched on a clinker silo at Lehigh Cement in Nazareth, Pennsylvania this female (Red, 20/CA, ID#24665) logged three data points on Amherst Island in Lake Ontario: 51 seconds on 17 and 19 July and three hours on 6 August. Without other locational data MOTUS cannot generate a map so I created one below with two points while her data is under review. Click here for her data table on the MOTUS website.

Proposed map of Nazareth Red peregrine, ID#24665, constructed by Kate St. John and enhanced MOTUS tracking data

Data uncertain: Pittsburgh, female, Blue, 19/CA (ID# 24664)

Interestingly there is a single 51-second data point for the Pittsburgh female (Blue, 19/CA, ID#24664) at Nazareth Red’s location on Amherst Island on 22 July. Its validity is uncertain. I marked it in orange on Nazareth’s map above.

Data uncertain: Bethlehem, male, Yellow, 60/AP (ID# 24666)

Bethlehem Yellow has a smattering of data points at the Allan Hills tower in Saskatchewan, but like the other Saskatchewan error this is 1,700 miles away from his banding site without any intervening locations. The data is under review.

As the MOTUS system gathers more information the picture for each bird will come into better focus. Meanwhile check out the tables and maps as they look today at the links below.

(photo of Pittsburgh juvenile peregrines by Lori Maggio, enhanced maps by Kate St. John from MOTUS tracking data; click on the captions to see the originals)

Eagle-Sized Roaming Charges

Steppe eagle (photo from Wikimedia Commons)

In case you missed it …

Steppe eagles (Aquila nipalensis), pictured above, breed on the steppes of Eurasia and spend the winter in Africa, the Middle East, Pakistan, India or Southeast Asia, passing through Central Asia on their way south.

Range of steppe eagle (map from Wikimedia Commons)

Steppe eagles are endangered in Russia and Central Asia, threatened by persecution and power lines which they encounter on migration so the Russian Raptor Research and Conservation Network has fitted 13 of them with cell-enabled backpacks to track their paths. They plan to mitigate the most dangerous locations frequented by eagles.

The tracking backpacks send four text messages a day with date, time and the eagles’ GPS coordinates. If the bird is far from the cell network, the tracker stores the data until the eagle gets near a tower.

Steppe eagle in flight (photo from Wikimedia Commons)

This method worked well in 2018 because most of the eagles traveled near the Russian cell network. This year, however, an eagle named Min spent the summer far from the network in a remote part of Kazakhstan. Her backpack stored months of data that it couldn’t transmit until she flew near a cell tower in Iran (map below).

Approximate route of Min in Fall 2019, inexpertly drawn by Kate St. John on a map from Pinterest

In October the researchers were stunned to receive a cellphone invoice with eagle-sized roaming charges. They’d budgeted 15 roubles/message but roaming in Iran is 49 roubles/message. In just one texting session Min used up the entire year’s budget for all the eagles!

What to do? They set up a crowd-funding appeal that raised more than enough to cover this year’s charges (100,000 roubles) and Russia’s Megafon network offered to cover the cost, too. So the project is saved.

Learn more about the steppe eagles’ migration and roaming charges here on the BBC. Follow the steppe eagles’ saga at the Russian Raptor Research and Conservation Network.

Click on the map below to see where the eagles have migrated in the past two years.

p.s. What is 100,000 worth in U.S. dollars? About $1,560.

(photos and range map from Wikimedia Commons, Min’s hand-drawn route on map from Pinterest, steppe eagles’ migration map from Russian Raptor Research and Conservation Network. Click on the captions to see the originals)

NOTES: Steppes are prairies or scrubland similar to the Great Plains and Great Basin of North America. Steppe eagles face an additional threat: Because they eat carrion they are dying of diclofenac, just as vultures are.

Monarchs Still Migrating Through Pittsburgh

Monarch butterfly in autumn (photo from Wikimedia Commons)

Though it’s nearly mid October I saw monarch butterflies migrating through Pittsburgh on Thursday and Friday October 10 & 11. Their timing seems late, but they were given a boost by August-like weather early this month.

You can follow their progress across the U.S. on Journey North’s monarch butterfly blog where you’ll find:

Today’s rain will put a damper on monarch migration in Pittsburgh but we can watch from afar as the butterflies make their way to Mexico.

(photo from Wikimedia Commons; click on the caption to see the original)

Establishing A Bridgehead

Asian lady beetles in the Netherlands (photo from Wikimedia Commons)

Now that the weather has changed unwelcome insects will invade our homes including Asian ladybeetles (Harmonia axyridis) that resemble native ladybugs but don’t act like them. Also called “harlequin ladybirds,” they overwinter indoors, make a stink, and bite when frightened.

A hundred years ago we thought this bug was a great idea and repeatedly introduced it to the U.S. to control aphids. The introduced ladybeetles never made it in the wild until a population was found thriving near New Orleans in 1988. After that they spread like wildfire across the eastern U.S. and into Canada.

Thirteen years later they became established in South America and Europe(*). By 2004 they were in southern Africa. They hadn’t been introduced. How did they get there?

A 2010 study of their genetic markers revealed that those three continents were invaded by the eastern North America population. In a move called the bridgehead effect, Asian ladybeetles in the U.S. used our continent as a jumping off point to colonize Europe, South America and Africa.

The bridgehead effect: Worldwide invasion of Asian lady beetles (map from PLOS One and NIH.gov)

The bridgehead effect is now recognized as a method of worldwide pest invasion. The pest establishes a bridgehead — a strong position near a human transportation hub — then fans out from there. Ants, obscure mealybugs and brown marmorated stinkbugs have spread this way.

Who will be the next pest to establish a bridgehead? I hope it won’t be the spotted lanternfly.

Read more at: Bridgehead Effect in the Worldwide Invasion of the Biocontrol Harlequin Ladybird.

(photo from Wikimedia Commons; map from PLOS One article posted at nih.gov. Click on the caption to see the original)

p.s. (*) The European population of H. axyridis is mixed. Some were directly introduced from their native range but were not considered pests until the North America cohort arrived.

From Broad Wings to Red Tails

Broad-winged hawk on migration (photo from Wikimedia Commons)

15 September 2019:

You can tell what month it is at a Pennsylvania hawk watch by noticing the most abundant raptor.

If you’re seeing a lot of broad-winged hawks, it must be September. Broad-wing migration peaks right now; they’ll be gone by the end of the month.

If you’re seeing a lot of turkey vultures and red-tailed hawks it must be October. In the fall of 2018, 90% of the turkey vultures that passed the Allegheny Front Hawk Watch went by in October.

Turkey vulture in flight (photo from Wikimedia Commons)

Red-tailed hawks spread their migration over several months. Last year at the Allegheny Front roughly 25% were seen in September, 50% in October, 25% in November.

Red-tailed hawk at the Allegheny Front, 31 October 2016 (photo by Steve Gosser)

If golden eagles are at their most abundant, it must be mid-October to mid-November. It’s my favorite time of year at the Allegheny Front.

Golden eagle at the Allegheny Front, 2 Nov 2016 (photo by Steve Gosser)

Pennsylvania hawk watches are about to switch from broad-wings to red-tails. Count the raptors to find out what month it is. 😉

(Broad-winged hawk and turkey vulture photos from Wikimedia Commons; click on the caption to see the originals. Red-tailed hawk and golden eagle by Steve Gosser)

Take A Birding Break

Click here to watch the video

Would you like to take a birding break?

Spend a few minutes watching fall warblers in Central Park in a video by Quoteny, recorded August to October 2014.

Enjoy the birds’ delicate beauty or challenge yourself to identify them, listed them below in order of appearance.

Click here to watch the video.

In order of appearance:

  • Magnolia warbler
  • Black-and-white warbler
  • Black-throated blue warbler
  • Common yellowthroat
  • American redstart (female or immature)
  • Palm warbler
  • Hooded warbler (adult male)
  • Northern parula
  • Yellow-rumped warbler (notice that in this view it isn’t showing any yellow)
  • Red-eyed vireo
  • Blackpoll warbler (bathing)
  • Northern waterthrush
  • Ovenbird (mesmerized by a rat)

(photo is a screenshot from video by quoteny on YouTube)