Category Archives: Migration

Humpback Whales Love Anchovies

Humpback whales lunge-feeding on anchovies in Monterey Bay (photo by Robin Agarwal via Flickr Creative Commons license)

25 January 2023

Every autumn humpback whales (Megaptera novaeangliae) migrate past California on their way to spend the winter off the coast of Mexico. They will linger, however, if they find lots of anchovies. Humpback whales love anchovies.

The California anchovy population typically rises and falls in 10 to 30 year cycles based on ocean conditions and fishing pressure. It surged in 2013 when the New York Times made this video (click on the image below) …

Screenshot from New York Times article... Click here or on the image to see the video

… and surged again this summer. In June 2022 there were so many anchovies that people reported small fish raining down from the sky in San Francisco, probably dropped by passing seabirds. In July anchovies were trapped in oxygen-poor water and died near shore, making a smelly mess.

There were still lots of anchovies when the whales showed up this fall. Robin Agarwal took a whale watch out of Monterey Bay in early October and captured these scenes of lunge-feeding humpback whales.

The anchovies crowded close as the predators approached. The whales forced them to the surface where the tiny fish leapt out of the water to escape.

Humpback Whales lunge-feeding on Northern Anchovies (photo by Robin Agarwal on Flickr)

The whales opened their mouths and anchovies fell in.

In a surge year for anchovies, people feast too.

Anchovies at Valley Bar + Bottle Shop, Sonoma, California (photo from Wikimedia Commons)

Read more about the 2013 anchovy surge in the New York Times: With Extra Anchovies and Whale Watching.

See more of Robin Gwen Agarwal’s photos here.

(humpback whale photos in Monterey Bay by Robin Gwen Agarwal on Flickr, Creative Commons license, food photo from Wikimedia Commons; click on the captions to see the originals)

A Rare Bird at Any Time of Year

Yellow-throated warbler at suet feeder in St. John’s, Newfoundland, 9 Dec 2022 (photo by Felip1 via Flickr Creative Commons license)

16 December 2022

A yellow-throated warbler (Setophaga dominica) would not be rare in Pittsburgh in early May but to see one in Canada in December is amazing.

This bird was photographed in St. John’s, Newfoundland on 9 December by Phillip (Felip1).

It’s not a very sharp picture but enough to identify him: a Yellow-throated warbler. He showed up for some suet early this morning.

I was half-expecting him. He had been visiting a suet feeder a couple of hundred metres away from us a few days ago. And one of the flickers had chopped up lotsa suet for him from the suet holder above. Those flickers are pigs but the other birds appreciate it.

Even though it is mid-December, the weather’s been mild and there are a half-dozen warblers who have apparently decided to try their luck to spend the winter around this town, St. John’s, Newfoundland, when all their relatives decamped a couple of months ago for more southern climes.

Felip1: Late Warbler, 9 December 2022

Pennsylvania is typically the northern limit of the yellow-throated warbler’s range and it’s a short-distance migrant to Florida and the Caribbean. St. John’s, Newfoundland is not even on the map (red arrow points toward it) but Newfoundland is about as far as Florida if you’re migrating from PA in the wrong direction.

Yellow-throated warbler range map from Wikimedia Commons. red arrow points toward St. John’s, Newfoundland which is off the edge of the map

The presence of this bird, one of half a dozen warblers in St. John’s in December, might be an after effect of Hurricane Fiona … and might not.

In any case its splash of yellow is a happy sight on a dreary day.

(photo by Felip1 on Flickr, Creative Commons non-commercial License)

Robins On The Move

Robins pause in a pine, California, Feb 2019 (photo by Douglas via Flickr Creative Commons license)

2 December 2022

In mid November hundreds, perhaps thousands, of American robins (Turdus migratorius) were in the east end of Pittsburgh but left abruptly when the weather dropped below freezing on November 18th. By the 21st it was 17 degrees F and the robins were long gone.

Robins can cope with cold weather but not with frozen ground so they stay just south of the freeze line as winter approaches.

American robin, Marin County, 16 Nov 2022 (photo by Robin Agarwal via Flickr Creative Commons license)

Those that nest in Canada and Alaska may leapfrog over the local slowpokes who wait for truly awful weather.

eBird distribution maps for June-July and December-February show that robins vacate the north to populate temperate zones in winter. June-July is dark purple with robins everywhere except for the hottest southern U.S. In Dec-Feb they’re concentrated in the Pacific Northwest and the Southeast including Florida.

Robins were on the move here in November. Now they’re south of us, wrapping up.

(photos by Robin Agarwal and Douglas on Flickr via Creative Commons license; click on the captions to see the originals)

Greater and White-Fronted

Greater white-fronted geese from Crossley ID Guide to Eastern Birds (image form Wikimedia Commons)

28 November 2022

Over the Thanksgiving weekend 6 greater white-fronted geese (Anser albifrons) showed up in western Pennsylvania — four in Lawrence County and four in Armstrong County.

Though they breed in the arctic around the world, the North American population stays west of the Mississippi. These geese are rare in Pennsylvania.

Range map of greater white-fronted goose embedded from

Their “greater” and “white-fronted” adjectives don’t make much sense unless you know the species they resemble in Europe.

They are “greater” because they are larger than the lesser white-fronted goose (Anser erythropus) that occurs only in Eurasia and is now Vulnerable to extinction.

They are “white-fronted” because they have white feathers on their faces surrounding their beaks, a field mark that distinguishes them from the similar greylag goose (Anser anser), another Eurasian species.

Greater white-fronted goose (detail from the Crossley ID Guide Eastern Birds, arrow added to indicate white front)

Only a handful of greater white-fronted geese are seen in western Pennsylvania in any given year, and then only in late October through early March.

If you see a goose that resembles this one check its field marks carefully. It may be an odd domestic goose, described here:

(images from Wikimedia Commons, map embedded from

Late November Birds at Duck Hollow

Ring-billed gull and common merganser, Duck Hollow, 23 Nov 2022 (photo by Charity Kheshgi)

26 November 2022

This week Charity Kheshgi and I saw ring-billed gulls (Larus delawarensis), a common merganser (Mergus merganser) and a few pied-billed grebes (Podilymbus podiceps) at Duck Hollow. All three species visit the Monongahela River in November when freshwater freezes up north.

Pied-billed grebe in silhouette, Duck Hollow, 23 Nov 2022 (photo by Charity Kheshgi)

The common merganser gave us an opportunity to mentally compare her field marks to a similar bird. Here are some tips.

Female common and red-breasted mergansers are so similar that it takes some practice to tell them apart. Charity’s photos show the common merganser’s two unique field marks:

  • A sharp demarcation between dark head versus white breast / gray back.
  • A sharply defined white under-chin.

Notice the common merganser field marks in three photos.

Common mergansers at Duck Hollow, 16 Nov 2022 (photo by Charity Kheshgi)
Common merganser, not showing its crest, Duck Hollow, 16 Nov 2022 (photo by Charity Kheshgi)
Common mergansers — unique field marks in blue (photo by Charity Kheshgi)

Female red-breasted mergansers (Mergus serrator) lack those sharp lines. The colors blend from one to the other.

Red-breasted merganser (photo from Wikimedia Commons)

Note that the presence of a head crest is not a reliable difference between the two; both can display it.

So here’s a quiz: Which species is in the photo below? Are these common or red-breasted mergansers?

Which merganser is this? (photo from Wikimedia Commons)

p.s. Location, location, location! Of the two species, common mergansers are inland birds more likely in Pittsburgh in November. Red-breasted mergansers concentrate at the coasts and Great Lakes in winter.

(photos by Charity Kheshgi and red-breasted mergansers from Wikimedia Commons)

Watch Your Feeders For Two Rare Birds

Evening grosbeak, January 2013 (photo by Steve Gosser)

21 November 2022

In September the Finch Research Network’s Winter Finch Forecast predicted that evening grosbeaks and pine siskins would irrupt southward this winter. In the past week Pennsylvania Rare Bird Alerts reported 55 sightings of evening grosbeaks and 11 of pine siskins in the state. Some are in western Pennsylvania right now and both are seed-eaters so you might see them at your feeders. Here’s what to look for.

Evening grosbeak (Coccothraustes vespertinus)

Evening grosbeaks are big bulky finches, larger than northern cardinals, that are shaped like rose-breasted grosbeaks. The male is bright yellow with black accents and white wing patches. When you see him at your feeder you’ll fall in love.

Male evening grosbeak (photo from Wikimedia Commons)
Male evening grosbeak seen from the back (photo from Wikimedia Commons)

The females and immature males are not as striking but still beautiful. In bright light they look like enormous goldfinches with fat necks and big beaks.

Female or immature male evening grosbeak (photo from Wikimedia Commons)

On gray days the females and immatures look drab but unmistakable for their size and huge beaks.

Female/immature evening grosbeak (photo from Wikimedia Commons)

Evening grosbeaks love sunflower seeds so keep some on hand to attract any that might be flying over. Doug Gross says they also love these wild foods: Seeds of box elder, ash, elm, tulip poplar, hackberry, pine, spruce, larch. Fruits of cherries, apples, crabapples, poison ivy, hawthorn, juniper (red cedar), Russian olive.

This PA map shows where evening grosbeaks have been reported in eBird this month through 20 Nov.

Evening grosbeak sightings in Pennsylvania and surrounding areas, Nov 1-20, 2022 (map from eBird)

p.s. How rare are evening grosbeaks? Their population has declined 90% in the past 50 years! Watch this video by Wild Excellence Films called Irruption: An Opportunity For Evening Grosbeak Conservation about David Yeany’s project to tag and track evening grosbeaks and learn more about the threats they face.

Pine siskin (Spinus pinus)

Pine siskins resemble female house finches but are warm brown in color (not gray-brown) and have sharp pointy beaks with a faint touch of yellow on their wings. They often hang out with goldfinches.

Pine siskin at feeder with American goldfinch (photo by Lauri Shaffer)

They love niger at the feeder and pull seeds from alder and arborvitae cones.

Pine siskins feasting on the seeds in alder cones (photo from Wikimedia Commons)

Though petite in size, pine siskins strenuously defend their feeder perches against other birds. Here one shouts at a male house finch.

Pine siskin yells at a house finch (photo by Tom Moeller)

Keep your niger feeder filled and look hard at those goldfinches. This PA map shows where pine siskins have been reported in eBird this month through 20 Nov.

Pine siskin sightings in Pennsylvania and surrounding areas, Nov 1-20, 2022 (map from eBird)

Watch your feeders for two rare birds. You may get lucky!

(photos by Steve Gosser, Lauri Shaffer, Tom Moeller and from Wikimedia Commons, maps from eBird; click on the linked captions to see the originals)

The Juncos Are Back

Dark-eyed junco, Cape Cod, Dec 2019 (photo by Bob Kroeger)

18 November 2022

This week’s first snow on 15 November brought in the “snowbirds,” an influx of juncos from the north and higher elevations. Kathy Saunders had fifteen at her feeders while it was snowing on Tuesday afternoon.

Our slate-colored juncos look so crisp and clean: Sparrow-like with dark eyes, pink beak, no stripes, charcoal gray head and back and wings, and a white belly — the “clean little coveralls” described in William Stafford’s poem Juncos.

Even though juncos have color variations all the birds with dark eyes are the same species: dark-eyed junco (Junco hyemalis).

This vintage blog from 2015 lists some of the subspecies, shows off a yellow-eyed junco (different species!) and describes a subspecies hybrid found in Pittsburgh last February.

(photo by Bob Kroeger)

Rare in Time or Place

Greater yellowlegs, Duck Hollow, 30 Oct 2022 (photo by Lisa Kaufman)

31 October 2022

Birds are considered rare when they show up at a time or place that’s unusual for them. The rarest are the birds out of place, two of which we saw yesterday at Duck Hollow.

The surf scoter (Melanitta perspicillata) first seen at Duck Hollow by John Flannigan on 26 October was still present on the 30th. Autumn is the right time of year to find a surf scoter migrating through Pennsylvania but Pittsburgh is a rare place to find one. Surf scoters nest in Alaska and northern Canada and spend the winter at the coasts.

We saw the scoter yesterday drifting downstream beyond the Homestead Grays Bridge in a view similar to Michelle Kienholz’s photo below. This dark and distant duck with a ‘Roman nose’ and some white on its head/face was a Life Bird for many in the group. (Click here for a better photo by Justin Kolakowski.)

Surf scoter at Duck Hollow, 26 Oct 2022, 5:44pm (photo by Michelle Kienholz)

Our favorite rare bird of the day was the greater yellowlegs (Tringa melanoleuca) that we heard before we found him. Greater yellowlegs had never been recorded at Duck Hollow in autumn and rarely show up in Allegheny County even in spring. They nest in Canada and Alaska and spend the winter near the US southern coasts and in Central and South America.

When we heard his call (similar to audio below) we went down to the shore to find him.

Greater and lesser yellowlegs are similar but our bird’s vocalization, his slightly upturned beak and his behavior were diagnostic.

Generally walks with high-stepping gait; occasionally runs with neck extended. Movements rapid and jerky.

Birds of the World, Greater Yellowlegs

Lisa Kaufman took many photos of him.

The Duck Hollow outing was a success even though we saw only 21 species. Here’s our list.

Duck Hollow, Allegheny, Pennsylvania, US
Oct 30, 2022 8:30 AM – 10:30 AM
Protocol: Traveling, 1.0 mile
21 species, 9 participants.

Canada Goose (Branta canadensis) 2
Mallard (Anas platyrhynchos) 12
Surf Scoter (Melanitta perspicillata) 1 Continuing bird, drifting down stream when we saw it
Common Merganser (Mergus merganser) 5
Killdeer (Charadrius vociferus) 2
Greater Yellowlegs (Tringa melanoleuca) 1 photos by participant Lisa Kaufman
Belted Kingfisher (Megaceryle alcyon) 1
Red-bellied Woodpecker (Melanerpes carolinus) 3
Downy Woodpecker (Dryobates pubescens) 2
Blue Jay (Cyanocitta cristata) 2
American Crow (Corvus brachyrhynchos) 1
Carolina Chickadee (Poecile carolinensis) 5
Golden-crowned Kinglet (Regulus satrapa) 1
White-breasted Nuthatch (Sitta carolinensis) 1
Carolina Wren (Thryothorus ludovicianus) 5
American Robin (Turdus migratorius) 16
Cedar Waxwing (Bombycilla cedrorum) 4
White-throated Sparrow (Zonotrichia albicollis) 11
Song Sparrow (Melospiza melodia) 2
Yellow-rumped Warbler (Setophaga coronata) 4
Northern Cardinal (Cardinalis cardinalis) 5

View this checklist online at

(photos by Lisa Kaufman and Michelle Kienholz)

From Warblers to Sparrows

Third northern parula, Frick Park, 14 Oct 2022 (photo by Charity Kheshgi)

17 October 2022

In just two days the mix of songbirds at Frick Park changed from warblers to thrushes and sparrows.

On Friday 14 October Charity Kheshgi and I found three northern parulas (Setophaga americana) along Nine Mile Run at Frick Park. eBird said they were worthy of a Rare Bird Alert. Fortunately Charity got photos of all three, shown in the slideshow below with three photos of each. Two of them are very easy to tell apart because they are at the extremes of bright vs. pale colors.

  • 1. First northern parula, Frick Park, 14 Oct 2022 (photo by Charity Kheshgi)

On Saturday night migration was intense which often means that all the birds leave Pittsburgh. Instead, on chilly Sunday morning we found a new mix of songbirds including those pictured below.

Blue headed vireo, Frick Park, 16 Oct 2022 (photo by Charity Kheshgi)
Golden-crowned kinglet, Frick Park, 16 Oct 2022 (photo by Charity Kheshgi)
Hermit thrush, Frick Park, 16 Oct 2022 (photo by Charity Kheshgi)
Gray-cheeked thrush, Frick Park, 16 Oct 2022 (photo by Charity Kheshgi)

There were many more American robins [50 instead of 7] and white-thoated sparrows (Zonotrichia albicollis) [36 instead of none] and we even heard a fox sparrow (Passerella iliaca) (example below). I wish we could have seen it.

Meanwhile we’re still waiting for dark-eyed juncos but not the snow that comes with them.

(photos by Charity Kheshgi)

Birds Love Water Features

Western bluebird bathing, California (photo from Wikimedia Commons)

14 October 2022

Songbirds are attracted to water — to streams, puddles, marshes, ponds — especially on migration.

Watch a soothing video of birds enjoying the water in Richard Hall’s backyard in Athens, Georgia.

Want to set up your own water feature? Here are three resources.

(photo from Wikimedia Commons, embedded tweet by @richhallecology)