Archive for the 'Migration' Category

May 04 2015

Coming To Lake Erie’s Shore

Published by under Migration

In early May millions of birds fly north in the night, then stop where they find good food, bad weather, or natural barriers that give them pause. By next weekend they’ll pile up at Lake Erie’s southern shore.

The best warbler “rest stops” are at Magee Marsh /Ottawa National Wildlife Refuge in Ohio and Presque Isle State Park, Pennsylvania.  The birds’ timing is so predictable that the second Saturday in May is always International Migratory Bird Day and the date of many bird festivals.

Warbler-viewing is excellent at the Magee Marsh Boardwalk but it’s very crowded as you can see in the video.  Ohio’s DNR expects 10,000 people along the Western Lake Erie Marshes birding loop  during the Biggest Week in American Birding.

If the crowds are too much for you, Presque Isle offers a calmer experience.  It’s also the site of Presque Isle Audubon’s Festival of the Birds.

Despite the crowds, I don’t want to miss my “warbler fix” in early May so I, too, will be flocking to Lake Erie’s shore.

 

p.s. So many Pittsburgh and Ohio birders visit Magee Marsh that you might recognize someone in the video. I did!

 

(YouTube “location preview” filmed at Magee Marsh Boardwalk in May 2013)

p.s. New arrivals at Schenley Park on May 4:  Scarlet tanager, least flycatcher, Blackburnian warbler, cerulean warbler.  There are so many Baltimore orioles that, though they only arrived last week, they are boring.

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Mar 24 2015

The Scouts Are Coming

Adult male purple martin (photo by Cajay on Wikimedia Commons)

You know Spring has sprung when the swallows return.  Tree swallows arrive first (seen in Allegheny County already!) but soon the bravest purple martins return from Brazil.  Though they rely on flying insects for food, adult males are so anxious to begin breeding that they fly home as soon as they can.

Purple martins (Progne subis) are cavity nesters with a long term relationship to humans.  Native Americans first provided nesting gourds and European immigrants followed suit so that now, for more than 100 years, all the purple martins in eastern North America nest in human provided housing.

Purple Martin house, Cape May Point, NJ (photo from Wikimedia Commons)

Last Thursday at Wissahickon Nature Club Bob Allnock, a purple martin landlord from Butler County, taught us about the housing and habits of these amazing birds.  We learned that the same purple martins return year after year to their successful nest sites.   The earliest males get the best condos so they hurry to get home.  The landlords call them “scouts.”

Scouts are always adult males who’ve bred before and know exactly where they’re going.  Adult females return later and then, weeks later, the subadult males and females arrive.  They’re in their first year of breeding and haven’t found a home yet.  If you’re trying to establish a new purple martin colony, these are the birds you wait for.

Right now purple martin landlords in western Pennsylvania are anxiously awaiting their first scouts.  As soon as one arrives the landlord updates the Purple Martin Conservation Association (PCMA) website with the date and location.  They also update when they see the first subadults so that landlords of unoccupied colonies can be on the lookout to attract these new birds.

How far north has Spring advanced? Where are they scouts right now?  Click here on the PCMA website for the Scout Report.

 

(photos from Wikimedia Commons. Click on the images to see the originals)

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Mar 16 2015

This Many!

Snow Geese take off from Middle Creek (photo by Kim Steininger)

How many snow geese are in this picture?  Imagine if it was your job to count them!

Snow goose migration got off to a slow start this spring because the lakes remained frozen in Pennsylvania.  In warm winters they start to arrive at Middle Creek Wildlife Management Area on the Lebanon-Lancaster County border in late February.  But that was out of the question this year.  The narrow north end of Chesapeake Bay was frozen in mid-February and there were 10-12 inches of ice on Middle Creek lake.  The geese stayed south.

The situation changed rapidly, though.  A week ago there were 100 snow geese at Middle Creek.  On Thursday March 12 there were suddenly 20,000.  On Friday there were 75,000 with more arriving throughout the day.  The count this morning is anyone’s guess.

Actually, the number of snow geese at Middle Creek is Jim Binder’s very educated estimate.  Jim has been the manager of Middle Creek WMA since 1997 and has decades of experience counting these birds.

The trick to counting is that snow geese always rest on the lake’s open water at night.  Jim comes out before dawn and counts them at first light before they leave for the day.  He knows the lake well and the numbers it can hold.  He’s so good at counting that he can tell the number by their sound.  The record is 180,000!

But Jim has to work fast. The flock wakes up and stretches its wings. Small groups leave in a leisurely fashion to feed in nearby fields but if something scares them — an airplane, a helicopter, or a bald eagle — the entire flock goes airborne at once with a roar.

When I want to see this spectacle I read Jim Binder’s snow goose count and arrive at Willow Point before dawn.  Kim Steininger took this photo on a day when there were 80,000 to 100,000 snow geese at Middle Creek.

How many snow geese do I hope for?  This many!

 

Note: Because the ice melted so late this year, snow goose migration is likely to be intense and over quickly.  The geese are running out of time to get home.

(photo by Kim Steininger)

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Feb 23 2015

Across The Sahara

Eleanora falcon with satellite tracking backpack (photo by Pacual López/ SINC via Science Daily)

When you know a bird’s winter and summer homes, can you guess the route it takes on migration?  Not necessarily.

Eleonora’s falcon (Falco eleonorae) spends the summer on islands in the Mediterranean and winters at Madagascar.  How does it travel from Europe to that big island east of Africa?  For decades ornithologists assumed it followed the coast — the Mediterranean Sea to the Red Sea to the Indian Ocean.

The assumption makes sense because in Europe Eleonora’s falcons eat small birds that they capture in the air over the sea.  Of course this falcon would take a water route … until a 2009 tracking study proved it wrong.

From 2007 to 2009, researchers from the Universities of Valencia and Alicante satellite tagged and tracked 16 Eleanora falcons on the Balearic and Columbretes Islands off the coast of Spain.  The data showed the falcons indeed spent the winter on Madagascar but they didn’t take the long, dog-leg coastal route to get there.

If you draw a straight line from the western Mediterranean to Madagascar it crosses 6,000 miles (more than 9,500 km) of the African continent.  That’s what the falcons did.  Flying both day and night they even crossed the Sahara.

Perhaps they were eating insects as they flew.  That’s what they do in Madagascar.

Read more here at EurekAlert.

 

(photo of satellite tagged Eleonor’as falcon by Pacual López/ SINC via EurekAlert)

 

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Jan 28 2015

Incredible Site Fidelity

Published by under Migration,Travel

Whimbrel ready for release in migration tracking study (photo by Barry Truitt, courtesy Center for Conservation Biology via William&Mary news)

Whimbrel ready about to be released for migration tracking study (photo by Barry Truitt, courtesy the Center for Conservation Biology)

The U.S. Virgin Islands are so beautiful it’s no wonder people come here every winter, year after year.  Some birds do too, and they show incredible site fidelity even in their choice of rest stops along the way.

Whimbrels are large shorebirds with long decurved bills who breed on the marshy tundra of Alaska, Northwest Canada and Hudson Bay.(*)  Their breeding season is short so they make 14,000 mile annual migrations to spend most of the year in Brazil or the Caribbean.  On migration they often use the same favored stopovers on the U.S. coast.  That’s how one particular whimbrel nicknamed Hope encountered biologists from William & Mary’s Center for Conservation Biology (CCB) in May 2009.

Since 2007 CCB had been tracking shorebird migration by fitting whimbrels with satellite backpacks at their staging areas on the Delmarva peninsula.  The satellite data, mapped by CCB and The Nature Conservancy, provided astonishing results.  For instance, from 2009 to 2011 Hope traveled faithfully from the Mackenzie River Delta to Great Pond at St.Croix, nearly always stopping at Delmarva along the way.

Migration journeys of Hope the Whimbrel, 2009 to 2011 (map from Center for Conservation Biology and The Nature Conservancy, courtesy Center for Conservation Biology)

Migration journeys of Hope the Whimbrel, 2009 to 2011 (map courtesy of the Center for Conservation Biology)

Her amazing migration made news at Audubon Magazine and EarthSky.org, and became a conservation story in the U.S. Virgin Islands.

In 2012 shortly after returning to St. Croix, Hope’s satellite antenna broke, rendering the tracking unit useless.  Rather than replace the unit, CCB decided to remove it and put colorful tags on her legs so that local birders could recognize her.  Here, Fletcher Smith holds her one last time before releasing her at Great Pond.

Fletcher Smith about to release Hope in St. Croix after removing her damaged satellite backpack, 2012 (photo courtesy the Center for Conservation Biology)

Fletcher Smith about to release Hope in St. Croix after removing her damaged satellite backpack, 2012 (photo courtesy of the Center for Conservation Biology)

 

Hope retired from the tracking program but she didn’t stop her normal life.  True to her habits, she still makes her faithful journey. In August 2013 she was photographed at St. Croix having completed her first round trip to Canada without the backpack.  Here she is sporting her yellow and green leg tags at Great Pond.  She’s there this winter, too.

Hope returns to Great Pond at St. Croix, U.S. Virgin Islands, August 2013 (photo from the Center for Conservation Biology)

Hope returns to Great Pond at St. Croix, August 2013 (photo courtesy of the Center for Conservation Biology)

We humans may visit the same places every year but for truly incredible site fidelity follow a whimbrel.

Read more about CCB’s Center for Conservation Biology shorebird tracking program and watch cool videos of the Mackenzie Delta and a whimbrel with chick here at the Center for Conservation Biology.

 

(photos and map courtesy of the Center for Conservation Biology)

And … two more messages:

1. Though I visited St. John, U.S. Virgin Islands I did not go to St. Croix to see “Hope.”  St. Croix is 43 miles south of St. John and there is no longer any ferry service. Like a whimbrel, you have to fly.

2. (*) These breeding and migration ranges refer to the Atlantic-migration whimbrels of North America.  Whimbrels have a worldwide distribution.

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Nov 15 2014

Swans On The Move

Tundra swan flock in migration (photo by Steve Gosser)

Tundra swans are migrating now over western Pennsylvania.  They’re traveling 3,600 miles from Canada’s Northwest Territory and Alaska’s North Slope to Chesapeake Bay and eastern North Carolina.

Steve Gosser photographed this flock on November 12.  I saw 60 at Moraine State Park on November 13.

The flocks are composed of families: mother, father and one or two youngsters.  In the fall their trip takes about 12 weeks, a slower pace than their springtime return because their “kids” are young and need to rest longer.

Sometimes they’re hard to see.  On an overcast day they’re white birds in a white sky so listen for their voices and look up.

Do you know their call?  Click here to hear.  Start the player at the 6:00 minute mark to hear a flock approach and land at Pungo Lake, North Carolina.

Tundra swans are on the move.

 

(photo by Steve Gosser)

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Nov 03 2014

Siskin Surge

Published by under Migration,Songbirds

Pine sisken (photo by Shawn Collins)

Ron Pittaway’s Winter Finch Forecast predicted pine siskins would move south this winter but no one expected the numbers seen in eastern Pennsylvania in the third week of October.

Hawk Mountain Sanctuary counted about 3,000 per day for several days, including 3,147 on October 23.  Andy Markel and Bill Oyler counted 739 heading southwest in Horse Valley, Franklin County on October 25.

Numbers were lower in western Pennsylvania where the largest count mentioned on PABIRDS was 50 on October 20 in Allegheny County.

Interestingly, Pittaway’s forecast accounts for this.  In his assessment of northern tree seed crops (i.e. finch food) he wrote:  “Spruce cone crops are variable in Ontario … East of Ontario cone crops are generally poor in the Atlantic Provinces, New York State, New Hampshire and other northern New England States.”  That means that pine siskins northeast of the Appalachians would certainly move through Pennsylvania while those directly north of Pittsburgh might find a good seed crop and not bother to fly this far south.

Though they’re still being reported in Pennsylvania the numbers are more normal now in random flocks of 15 to 20 — at least on PABIRDS.

Where will that surge of siskins end up?  West Virginia?  The Great Smoky Mountains (where it snowed already)?  It’s probably too soon to tell.

 

(photo by Shawn Collins, Crawford County, 2 November 2014)

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Oct 18 2014

Lots Of Robins

Published by under Migration

Flock of American rovins on the grass (photo by Marcy Cunkelman)

Have you tried counting robins lately?  This week it’s been a challenge.

Though it may seem pointless I usually count birds when I’m outdoors.  The reward comes later when I look back at the numbers.

Based on my counts I know that a first wave of migrating American robins came through Pittsburgh in September.  Their numbers dropped, but a second wave arrived last week to feast on the fruit in the city’s trees and bushes.

Unfortunately these birds are camouflaged by the autumn foliage.  Rust-and-brown robins match rust-and-brown leaves.  On walks in Brookline, Oakland and Squirrel Hill I counted 20, 50, 100 robins.  Why the round numbers?  I don’t know exactly how many there were.

All I know for sure is:  There are lots of robins right now.

 

(photo by Marcy Cunkleman)

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Oct 15 2014

Hybrid Migration

Swainson's Thrush (photo by Matt Reinbold, Bismarck ND, from Wikimedia Commons)

If you’re a Swainson’s thrush of mixed parentage you’ll probably pick a bad migration route.  It’s in your genes.

In eastern North America we see only one subspecies of Swainson’s thrush, the olive-backed (above), but in British Columbia there are two.  The russet-backed subspecies breeds along the Pacific coast and follows the coast to spend the winter in Mexico and Costa Rica.  The olive-backed subspecies breeds in the interior and migrates across the continent and the Gulf of Mexico to winter in South America.

Where their breeding ranges meet the thrushes pair up without regard to these distinctions.  Their hybrid offspring inherit a mixture from their parents, including mixed coloration.

Kira Delmore at the University of British Columbia wondered if the hybridization extended to their migration routes so she tagged hybrid Swainson’s thrushes with light-level geolocators to track their routes.

The data proved that their migration routes are inherited and that those of mixed parentage inherit a blend.  While each parent would have followed the Pacific coast or a safe route across the continent, the hybrids chose novel and dangerous compromises between the two paths.

“Instead of taking well-trodden paths through fertile areas, these birds choose to scale mountains and cross deserts,” said Delmore.

The dangerous routes probably cause more hybrids to die on migration than their pure counterparts, thus keeping the subspecies distinct.  Says Delmore, “The self-destructive behavior of hybrids could be helping to maintain the great diversity of songbirds we enjoy.”

Read more about this study here at Science Daily.

 

(photo by Matt Reinbold from Wikimedia Commons. Click on the image to see the original)

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Oct 01 2014

The Blue Jay Forecast

Published by under Migration,Songbirds

Blue Jay (photo by Steve Gosser)

When folks wonder why blue jays are scarce they turn to the Internet and find my 2012 blog post “Have You Seen Any Blue Jays Lately?”   In the past two+ years 116 readers have commented on the status of blue jays where they live.

The most recent comments are on the absence of jays:  Where have they gone?  Why did they leave?  When will they come back … if at all?

Over the winter blue jays eat acorns, beechnuts, hazelnuts, hickory nuts and other mast (nuts).  Their range map looks as if they never migrate but they will leave if nuts are scarce.

How can we know if the blue jays will leave? Check the Blue Jay Forecast.

Every fall Ron Pittaway produces a Winter Finch Forecast for Canada based on the abundance of tree seeds in Canada’s forests.  The finches in his report eat a wide variety of seeds including spruce, fir, birch and mountain ash.  If food is abundant the birds stay home all winter.  In poor mast years they irrupt southward.  Here in Pennsylvania we wait for Pittaway’s forecast to tell us which species will visit us in coming months.

Blue jays depend on tree nuts too and they often move when the finches do, so Pittaway includes them in his forecast.  This year he says “Expect a good to heavy flight (many more than last year) moving westward along the north shorelines of Lakes Ontario and Erie because the acorn, beechnut, hazelnut and soft mast crops averaged low in northeastern, central and eastern Ontario.”

If you live in Ontario, don’t expect to see a lot of blue jays this winter.  Lots of them are in Pittsburgh — at least right now.  Guess where they came from.   😉

Click here for Ron Pittaway’s Winter Finch Forecast.   Scroll down to read about blue jays.

 

(photo by Steve Gosser)

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