Archive for the 'Migration' Category

Sep 28 2016

Bad Flu is Not Our Fault

Flock of ducks (photo by Brian Herman)

Flock of ducks (photo by Brian Herman)

Right now it’s flu shot season, soon to be followed by flu season itself from December to March.

Wild birds have been blamed as a source of influenza but new evidence indicates they’re not the cause of bad flu.  To understand why here’s a primer on where flu comes from, how it spreads, and why flu season is in the winter.

Where does flu come from?

Other people!  It spreads best — and quickly creates new strains — where people are densely crowded.  Amazingly, the Spanish Flu Epidemic of 1918 spread quickly because of crowded camps and trenches in World War I.  A new study this month from the University of Chicago finds that “surveillance for developing new, seasonal vaccines should be focused on areas of east, south and southeast Asia where population size and community dynamics can increase transmission of endemic strains of the flu.”  Click here to read why flu does so well in that part of the world.

How does flu spreadIn the air.  We breathe it in.  Airborne transmission actually explains …

Why is flu season in the winter?

Not too long ago we were told that it’s in the winter because migratory waterfowl pass avian flu to domestic birds during fall migration.  Wrong!!

Recent studies of avian flu transmission show that it spreads in poultry factory farms (crowded conditions!) and along our poultry trade routes.  It follows our poultry, not wild birds’ migratory paths.

And the timing has nothing to do with migration.  Flu season is in the winter because the pathogen stays airborne longer in dry winter air.  It falls to the ground in summer humidity.

So why are waterfowl off the hook?

Wild birds aren’t spreading the worst strains of avian flu because they don’t have it.

After the H5 avian influenza A virus hit U.S. poultry farms in 2014-15, officials worried that avian flu would return when waterfowl migrated south again … but it didn’t.  The reason was found by researchers from St.Jude Children’s Research Hospital who “analyzed throat swabs and biological samples taken from 22,892 wild ducks and other aquatic birds collected before, during and after a 2014-15 H5 flu outbreak in poultry.”(*)  None of the birds had the highly pathogenic influenza A virus.

“Bad flu is not our fault,” say the ducks.

Read more here at: Evidence suggests migratory birds are not a reservoir for highly pathogenic flu viruses.


p.s.  Remember to get a flu shot!  However, if you’re over 65 immunologist Laura Haynes says you should get it after Halloween if you can.  Click here to read her advice on NPR.

(photo by Brian Herman)

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Sep 26 2016

Guess Who’s Coming To Visit

Published by under Migration

Red-breasted nuthatch (photo by Shawn Collins)

Red-breasted nuthatch (photo by Shawn Collins)

Guess who’s coming to visit our bird feeders this winter.

Every year Ron Pittaway analyzes the seed crop in Canada’s forest and predicts where northern finches and irruptive songbirds will spend the winter.  Last week he published his 2016 Winter Finch Forecast and the news is mixed.

Pittaway says the seed crop is poor this fall in southeastern Canada so many seed eaters will go west or north where the crop’s been good.  We won’t see crossbills this winter but three species are certain to move south: red-breasted nuthatches, blue jays and purple finches.

Red-breasted nuthatches (above) have already arrived in western Pennsylvania.  I saw one in my City neighborhood last week.

As for blue jays, we’re inundated with them in Pittsburgh especially in Schenley Park.

Blue Jay (photo by Chuck Tague)

Blue Jay (photo by Chuck Tague)


Purple finches have been reported in central Pennsylvania but I’m still waiting for my first one here in the west.

Purple finch (photo by Chuck Tague)

Purple finch (photo by Chuck Tague)

Keep your feeders filled and don’t be disappointed if you attract a lot of blue jays.  They’re visiting from Canada.  🙂


(Red-breasted nuthatch photo by Shawn Collins. Blue jay and purple finch photos by Chuck Tague)

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Sep 12 2016

Chestnut-Sided Is Yellow Capped

Published by under Migration,Songbirds

Chestnut-sided warbler, Spring and Fall (photos by Andy Reago & Chrissy McClarren via Wikimedia Commons)

Chestnut-sided warbler, Spring and Fall (photos by Andy Reago & Chrissy McClarren via Wikimedia Commons)

Finally!  Last night’s north wind generated intense bird migration from the northeastern U.S. to Texas.  Here’s the 10:30pm EDT radar mosaic.  Wow!

A good night for migration in the eastern U.S. (radar mosaic from NWS, 11 Sep 2016, 22:28 EDT)

A good night for migration in the eastern U.S. (radar mosaic from NWS, 11 Sep 2016, 22:28 EDT)

This morning we’ll find lots of new arrivals from Pittsburgh to the Gulf Coast. Among them will be chestnut-sided warblers that no longer live up to their name.

In the spring (at left above) both sexes of the chestnut-sided warbler (Setophaga pensylvanica) have brownish red “chestnut” sides with a black eye line and malar stripes.  Their undersides are clear white from throat to tail and they have wing bars, yellow wing patches, a yellow cap, and something we rarely notice — yellow backs with black stripes.

In the fall their black accents are gone and most are missing the chestnut sides. Instead they have white eye rings!  The right hand photo shows this amazing transformation.

Fall chestnut-sided warblers retain their clear white throats and bellies, yellow wing bars, and their distinguishing characteristic — the yellow on top of their heads.  The color is muted now to yellow-green and extends to the nape and back.

What happened to the chestnut sides?  Adult males have a hint of chestnut, shown in the right hand photo, but the females and juveniles are missing it.  And just to make you crazy, fall bay-breasted warblers have chestnut sides and yellowish heads — but no eye ring.

So don’t expect to find a chestnut-sided warbler today.  Watch for the yellowish cap.


(chestnut-sided warbler comparison photos by Andy Reago & Chrissy McClarren via Wikimedia Commons. Click on these links to see the original photos in spring and fall)



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Sep 10 2016

Avoiding Bad Weather

Published by under Migration

NOAA Doppler radar, national mosaic, 7 Sept 2016, 5:18am EDT (image from

NOAA Doppler radar, national mosaic, 7 Sept 2016, 5:18am EDT (image from

While traveling in Maine I kept in touch with home by reading the bird sightings on PABIRDS.  It was torture.  All the good warblers were in Pennsylvania, none in Maine.

Though Tropical Storm Hermine never made it to the Gulf of Maine it affected the weather from afar.  While Hermine spun itself out off the coast of New Jersey migrating birds avoided the northeast.

In the Doppler radar mosaic before dawn on Wednesday morning, Sept 7, you can see migrating birds as swaths of pale blue traveling through Illinois, Indiana and Kentucky to the coast of Georgia. The entire northeast is blank.

Now that I’m heading home the wind is about to change in Maine and birding will be good again.

Alas. The birds avoided bad weather but I could not.


(radar mosaic map from

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Sep 01 2016

A Tip on Confusing Fall Warblers

Female yellow warbler (photo by Chuck Tague)

Female yellow warbler (photo by Chuck Tague)

On Throw Back Thursday:

It’s warbler time again as these tiny birds migrate south through western Pennsylvania.  They’re not as much fun as they were in the spring.

In May they were dressed in their colorful best.  This month a lot of them are wearing camouflage.  Who are these confusing fall warblers?

Back in 2009 it dawned on me that I could identify immature fall warblers because I had looked hard at their parents in the spring.  Read how it works here:

Confusing Fall Warblers


(photo by Chuck Tague)

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Aug 31 2016

It’s Time To Watch Chimneys

Across North America chimney swifts (Chaetura pelagica) and their look-alike western cousins, Vaux’s swifts (Chaetura vauxi), are migrating south for the winter.


Chimney swift trio (photo by Jeff Davis)

Chimney swift trio (photo by Jeff Davis)

Swifts eat flying insects so they migrate during the day when the insects are out.  On hot days they circle high, coursing back and forth in the clouds of bugs.  It doesn’t look like organized migration but they’re tending ever southward while they eat.

At dusk the swifts gather at big chimneys, circle in a vortex, then pop into the chimneys to roost, as shown in the video.  On cold rainy days they roost during the day to conserve energy when the bugs don’t fly.

Vaux’s swifts are on their way to Central America but the chimney swifts will go much further, crossing the Gulf of Mexico to spend the winter in Columbia, Peru, Ecuador and western Brazil. I wonder if their over-water migration gave them the species name “pelagica.”

For the next several weeks, watch chimneys at dusk to see the swifts.  Click here for suggested sites in Pittsburgh.


(video from Cornell Lab of Ornithology on YouTube, swifts photo by Jeff Davis)

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Aug 25 2016

On Their Way to Veracruz

Published by under Migration

Pair of Prothonotary Warblers courting (photo by Kim Steininger)

Pair of Prothonotary Warblers courting (photo by Kim Steininger)

On Throw Back Thursday:

It’s still summer but North America’s warblers are already on migration to their winter homes.

Beginning in August, prothonotary warblers (Protonotaria citrea) spend three months in transit. Read more about where they go and how they spend their time in this article from August 2009.

Leaving Now for Veracruz


(photo by Kim Steininger)

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Aug 24 2016

Which One of You Is Least?

Two "peeps" (photo by Mike Baird, Morro Bay, CA via Wikimedia Commons)

Two “peeps” (photo by Mike Baird via Wikimedia Commons)

Which one of you is a least sandpiper?  That’s the question I ask all the “peeps” when I see them in the field.

This month I’ve been using the tips I wrote in Shorebird Practice on August 12 to find the answers. Here’s how:

  • Which small shorebirds are possible here and now? In western Pennsylvania in August the likely suspects are least sandpipers, semipalmated sandpipers, and at sandy shores, sanderlings.  At muddy locations you might encounter the relatively rare Baird’s sandpiper.  He’s longer-winged than the other three.
  • Are you at a sandy beach?  If not, rule out sanderlings.  If yes, examine behavior and size. Sanderlings walk on sand, they chase the waves, and they’re noticeably bigger than least and semipalmated.  Sanderlings also look whiter than the other two.
  • Size: Least and semipalmated are smaller than all the other species.
  • Legs:  If you can see colors and the birds legs aren’t muddy you’ve hit the jackpot.  Least sandpipers are the only peeps with yellow or greenish legs.   If you cannot see leg color then …
  • Posture while feeding:  Imagine a person knee-bending (least) versus extended out to reach something (semipalmated).
    • Least sandpipers crouch with bent legs and peck near their toes.  They look hunched.
    • Semipalmated sandpipers reach out with their bills to find food. They look stretched out and their tails may be cocked higher.
    • (Western and semipalmated postures are similar. Fortunately, there are no westerns here and now.)
  • Bills:  All are black.
    • Least sandpiper bills taper to a fine point with slight droop at the tip.
    • Semipalmated bills are shorter and straight, sometimes slightly blunt at the tip.
  • Micro-habitat: According to Pete Dunne’s Essential Field Guide Companion:  “Any lone peep in marginal habitat is likely to be a Least (baked mud or tight watery leads flanked by rank tiny puddles).”  They say that leasts like edges.

So which one of the birds above is a least sandpiper?  It’s a trick question.  Both are.  And yet they’re standing up to their bellies in water to confound the “leasts liked edges” statement.  Notice their yellow legs.


p.s. Here are two extensive resources on identifying peeps:  ABA’s in-depth identification of peeps and Peep identification at The Nutty Birder website.

(photo by Mike Baird from Wikimedia Commons. Click on the image to see the original.)

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Jul 19 2016

Lesser or Greater?

Lesser yellowlegs and Greater yellowlegs (photos by Bobby Greene)

Lesser yellowlegs and Greater yellowlegs (photos by Bobby Greene)

Robins and song sparrows are still nesting but shorebird migration has already begun.  Lesser yellowlegs (Tringa flavipes) have already arrived in western Pennsylvania and will be followed soon by their look-alike cousins, the greater yellowlegs (Tringa melanoleuca).

How do you identify these similar birds?

First, they’re different from other shorebirds.  Though their plumage may confuse you, these are tall long-billed birds with uniquely bright long yellow legs.  Both of them will wade and swim in deep water.  (The solitary sandpiper, also a Tringa, is shorter with greenish legs.)

And they’re different from each other.  If a lesser and greater yellowlegs are in the same pond they’re easy to distinguish by size — greater is bigger than lesser — but you’re not usually that lucky. Here are some additional clues:

Character Lesser Greater
Bills The bill is only as long as its head. Measure the underside from the chin. Bill is longer than its head front-to-back.
Call Tu …or… Tu-Tu (1 or 2 Tu’s) Tu-Tu-Tu (3 or 4 Tu’s in a row) This bird is noisy! Will give a single Tu over and over when agitated. The way to remember greater vs lesser: 3 Tus are greater than 1.
Body size Dainty, slender, weighs 2.8 oz Substantial, a bit bulky, weighs 6 oz
Behavior Dainty. Picks at surface or under water. Runs sometimes. When feeding appears angry, aggressive(*). Runs with long strides. Chases fish. Almost like a reddish egret but without the wing-dance steps.
Solo? Hangs out with other birds Tends to be solo or with other waders

(*) descriptions from Pete Dunne’s Essential Field Guide Companion.



Using the information above can you tell who’s who in the video?  Behavior is a good clue even when there’s only one bird.


You’ll find these birds at wetlands, ponds, quiet rivers and lakes.

If you’re not sure who’s who you can always call them “yellowlegs.”


(photos by Robert “Bobby” Greene, Jr. video by Mark Vance on YouTube)

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May 14 2016

It’s Bird Day!

Spotted sandpiper in breeding plumage (photo by Bobby Greene)

Spotted sandpiper in breeding plumage (photo by Bobby Greene)

Today is International Migratory Bird Day in the U.S. and Canada.

Though birds migrate during many months of the year their biggest push in North America is in early May.  That’s why we celebrate their arrival and promote their conservation on this second Saturday.

In May migrating birds pass overhead at night and stop to eat in unlikely places where they don’t intend to stay.  Yesterday I saw a spotted sandpiper (pictured above) at Schenley Park’s Panther Hollow Lake.  Shorebirds and wading birds are rare visitors to the lake because the concrete edge provides no food.  The sandpiper paused for a snack at the cat-tails and creek outflow … and then he was on his way to breed at a stream bank, lake or river.

Lake Erie’s southern shore is a great place to find migratory birds this month.  Last week I went birding from Erie, Pennsylvania to Maumee Bay, Ohio.  Here are two of my favorite species seen at Magee Marsh, Ohio — one very large species and one small.

American white pelicans flying over Chase Lake NWR, North Dakota (photo from USFW via Wikimedia Commons)

American white pelicans flying over Chase Lake NWR, North Dakota (photo from US Fish & Wildlife via Wikimedia Commons)

Canada Warbler (photo by Cris Hamilton)

Canada Warbler (photo by Cris Hamilton)

American white pelicans and Canada warblers don’t breed at Magee Marsh but they’re there this month.

Don’t miss the migration on International Migratory Bird Day.  Get outdoors in May!


(photo credits: Spotted sandpiper by Bobby Greene,
American white pelicans by US Fish & Wildlife via Wikimedia Commons.
Canada warbler by Cris Hamilton

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