Outside My Window

Yesterday a mourning dove arrived at my feeder with a clenched foot, probably suffering from frostbite.  The temperature was 9^oF when I saw him.  It had been 2^o at dawn.

Even in severe cold weather we rarely see birds with frostbitten feet so we tend to forget that it’s possible.  Gulls and Canada geese stand on ice, cardinals and chickadees hop on snow, and we take for granted that their bare feet won’t be hurt as ours would be. 

For most birds this is because of a very special adaption that allows their feet to be cold in comfort.  Birds’ feet have fewer nerves and blood vessels and a unique circulatory system.  The veins and arteries in their legs are intertwined so that cold blood leaving their feet is warmed by the arteries delivering warm blood.  As Dr. Tony Bledsoe pointed out, “This operates as a counter-current exchange system, so that nearly all of the warmth in the descending blood is transferred to the ascending blood.”  

For some reason this system isn’t as effective in mourning doves and their feet are prone to freezing.  Since they’re a game bird (did you know they’re hunted in 38 states?) they’ve been studied extensively.  In one study, mourning doves with frostbitten feet were rescued.  They recovered from their injuries in six weeks but their damaged toes fell off.  They survived to a normal life span with fewer toes, but life is short for a mourning dove anyway.  Their average adult life expectancy is only one year. 

I felt bad for the bird at my feeder but I know that if he has enough to eat he’ll survive.  The real killer right now is lack of food and since mourning doves eat from the ground their food is repeatedly covered by snowfall. 

I’ll keep my feeders filled and hope for the best.

(photo by Marcy Cunkelman)

Today is one of the heaviest travel days in the U.S. so I thought it an appropriate time to tell you that the roads may be congested overhead as well.  That’s because birds sometimes use them for navigation.

This is not a new discovery.  People who race pigeons had noticed that their birds seemed to follow roads – big roads – when racing home.  It wasn’t possible to prove this however until 2004 when GPS tracking technology got small enough to put on the back of a racing pigeon.

They tested the theory near Rome where they released racing pigeons 20-80 km from their lofts.  Researchers found that the experienced birds tended to follow roads and railroad tracks until they were relatively close to home.  If a bird had flown the route before it was much more likely to use a road as a guide.  Some birds even went out of their way to stay on the road and turn only at intersections.

Why do they do this?  Perhaps because it frees up their minds for focusing on other things.

And why do we prefer expressways?  Perhaps for the same reason … except that our minds are very busy today because the traffic is so bad.

For more information click here for the online article.

(photo by Alan D. Wilson www.naturespicsonline.com, in the public domain under the Creative Commons Attribution ShareAlike 2.5 license at Wikimedia)

This wild turkey is smart.  She lives where people feed her instead of where she feeds people. 

She’s the biological ancestor of the domestic turkeys we’re eating today but she has nothing to worry about.  Way back when, the Aztecs domesticated turkeys for a ready supply of eggs and meat.  Since then turkeys have been bred to match our tastes, and our tastes have changed so much that most people don’t like the game-y meat of the wild bird.

Having turkey for dinner today?  “Don’t look at me,” she says.

(photo by Sam Leinhardt of a wild turkey who nested behind his backyard.)

I am happy to report that this bird, the lowly pigeon, is faster than the Internet.  Yes, faster than broadband. 

An I.T. company proved it recently when users of South Africa’s largest Internet provider, Telkom, complained their ADSL broadband speeds were so slow it would be faster to deliver the information via carrier pigeon. 

Always up for a challenge the pigeons responded, “Bring it on!”   They deputized a carrier pigeon named Winston to fly a 4GB memory stick 60 miles from Howick to Durban.

As Winston’s owner released him on his journey, staff at Unlimited IT clicked on the download button to start transferring the same 4GB over the Internet from their Howick to Durban offices.

Winston made the trip in 1 hour 8 minutes.  Broadband delivered the data in nearly twice the time: 2 hours 6 minutes.

So if you want to deliver a lot of data quickly, hire a pigeon.

For the BBC video of this amazing feat, click here. 

(photo by Chuck Tague)

Until quite recently, pigeons had a noble reputation.  Their homing instincts made them critical message carriers especially in times of war.

Pigeons changed the course of history from the time of the ancient Greeks until the mid 20th century.  Armies on the move carried cages full of pigeons ready to send news to headquarters.  To deliver a message they tied a capsule to a pigeon and released the bird.  The pigeon immediately flew home.  Ta dah!

This was a great advantage for the first army to use pigeons, but it didn’t take long for both sides to figure out they could kill the birds and intercept the messages.

Pigeons were critical in the Franco-Prussian War and the seige of Paris when microphotography allowed one bird to carry up to 30,000 messages.  The birds were used extensively in World War I.  A pigeon even saved an American battalion that was trapped behind enemy lines and bombarded by friendly fire.  The soldiers released several birds but all were killed except Cher Ami.  Though seriously wounded, Cher Ami continued his 25-mile mission, delivered the message and stopped the shelling.  After he recovered, though missing an eye, he was awarded the French “Croix de Guerre.”

Pigeons continued to carry messages during World War II, especially for spying and situations that required radio silence.  They even carried cameras that took pictures behind enemy lines, a pre-satellite form of aerial surveillance.  Pigeons were considered so important that both the British and the Germans used peregrines to kill the enemy’s messengers.  This wasn’t totally successful because the peregrines didn’t ask whose side the pigeon was on before killing it.

The age of electronic communication put pigeons out of a job.  The last military use(*) of pigeons was in the 1970s when the U.S. Coast Guard discovered the birds recognize shapes and are much better than humans at finding people and equipment lost at sea.  This program never made it beyond the testing phase, though.  It ended during budget cuts.

Since then the pigeon’s reputation has gone sour.  Few people remember the glory days (I don’t) and most have little respect when they see large flocks pecking seed on the sidewalk.

But there’s a glimmer in this dark cloud.  Pigeons continue to help people through scientific research – from bird navigation to power napping.  If a pigeon helps find the cure for cancer, we’ll all be grateful.  Maybe then the glory days will return.

(photo by Chuck Tague)

(*) p.s. I take that back!  The U.S. military used pigeons as gas detectors in the early days of the Iraq War.

p.s. #2.   Just found a Dec 27th blog on this subject with additional information on the pigeons of war.

This wild turkey is glad to be strutting his stuff while you’re eating domestically raised turkey today.  Even if you’re eating a wild bird he’s grateful that people like to hunt turkeys. 

As you can imagine, this makes for a complicated story.

When Europeans came to America, hunting was unregulated and turkeys were very popular food.  By the late 1800s, hunting and deforestation had taken its toll.  Only a few thousand turkeys remained in all of Pennsylvania. 

At that point the newly formed PA Game Commission began studying the turkey population and regulating the hunting season.  There were so few turkeys that hunting was banned for a few years.  The Game Commission even stocked turkeys bought from Mexico.  Then in 1929 they acquired land and began to raise turkeys for release into the wild.

Propagation programs, habitat restoration and hunting regulations turned the tide.  Today Pennsylvania’s wild turkey population is thriving.  They are easy to find just about everywhere, even in Pittsburgh’s city parks: Frick, Schenley, Riverview and Highland.  My favorite flock of turkeys used to hang out at the “French fry sculpture” on Bigelow Boulevard.

So on Thanksgiving Day, Tom Turkey is grateful to the PA Game Commission for making his comeback possible.  He is also thankful that Americans prefer to eat domestic turkeys.

(PGC photo of a male Wild Turkey in full display, courtesy of the PA Game Commission’s Photo Gallery)

More baby pictures!

Tim Vechter sent me this one of a wild turkey chick he found with mother and siblings in a field near Latrobe.

As you can see, this baby bird is well camouflaged.  Wild turkeys lay 10-14 eggs in a nest on the ground.  As soon as the chicks hatch they’re ready to go.  Their mother calls and they walk off the nest and disappear in the tall grass.

The last time I saw wild turkey chicks I literally stumbled on them.  I was at Ohiopyle State Park when I saw the weeds move and a baby turkey darted across the trail.  Then another.  Mom called and they all ran back.  If I hadn’t had my wits about me I would have stepped on one.

Fortunately I knew not to mess with baby turkeys.  They may look cute and defenseless but their mother is formidable, willing to march right up to danger and attack it.

Dad, on the other hand, has a hands off attitude toward family life.  Turkeys are polygamous so he has a territory and up to five hens to maintain.  He spends breeding season cruising around making sure he’s in charge.  To him, everything takes care of itself.  His wives raise the kids and the kids find food on their own.

What more could he want?

(photo by Tim Vechter)

…but two pigeons in the Pitt peregrines’ nest box!

Based on the time stamp on this photo, the pigeons showed up in Dorothy and E2′s nest only 20 minutes after I posted my blog about pigeon overpopulation yesterday. 

Do they have ESP?  Did they read my blog and decide to make a point?  Did they get the feeling they ought to put in a defiant appearance?

Obviously the peregrines weren’t paying attention.  They’ve been napping a lot because they’re molting.  

Yesterday at lunch my friend Karen and I saw Dorothy and E2 perched in nooks on the edge of the 32nd floor, facing the wall, their backs to the world.  I guess if you’re at the top of the food chain you can turn your back to the world with confidence.

No need to worry the peregrines will go hungry.  They can have breakfast in bed if they want!

(photo from the National Aviary falconcam at University of Pittsburgh)

Being a peregrine fanatic I’m kind of fond of pigeons – at least from the prey point of view – so when I was in downtown Pittsburgh on Sunday I stopped by Mellon Square to check out the scene.

Even for a peregrine falcon the number of pigeons at Mellon Square is way too much of a good thing.  I counted more than 150 and I couldn’t see all of them.  The pigeons outnumbered people more than 30 to 1.

This explains why peregrines hang out on the Oliver Building window sills.  It’s like visiting an all-you-can-eat restaurant.  The food may not be that great but there’s so much of it!

This kind of pigeon over-population repulses most people and they want a quick fix, the quickest being poison.  But if you poison a pigeon, you’ll poison a peregrine.  After a culling episode pigeons reproduce fast to fill the void – in fact lethal control actually increases the flock - but the peregrines take years to recover.  And peregrines are endangered in Pennsylvania.  It’s bad, bad, bad to poison an endangered species.

So what to do?

Pigeons need two things to reach the numbers found at Mellon Square:  lots of food and places to nest.  They reproduce in direct proportion to their food supply.  If food is scarce some won’t nest at all.  If food is plentiful they lay the next clutch of eggs before the first set has hatched, producing more than 12 chicks per year. 

The food problem is obvious.  Sidewalks at Mellon Square are coated with bird seed.  Control the food source (the people who feed them) and you’ve got most of the problem licked.   To make a really dramatic difference, control the nest sites as well. 

City pigeons nest on buildings and bridges.  They also nest in buildings.   Find the buildings involved and spend the time and money to block the access holes.  Last summer the University of Pittsburgh cleaned the Cathedral of Learning and blocked off the pigeon nest holes as part of the cleaning job.  One year later there are far fewer pigeons at Schenley Plaza. 

And finally, there’s a foolproof solution that makes both the pigeon-feeders and the pigeon-haters happy.  Many European cities have solved their pigeon problem permanently by building dovecotes and pigeon lofts.  Yes, they built nest sites.  They control the population at the dovecotes by substituting dummy eggs and they control the food level by giving pigeon lovers an approved place to feed and interact with the birds.  

This keeps the pigeons and the birdseed off the street.  An elegant solution. 

(photo by Chuck Tague)

Pigeons are the peregrines’ favorite food so this snapshot from the Pitt peregrine webcam made me laugh out loud.  What the heck is this pigeon doing in the nest of his mortal enemies?

Pigeons nest on cliffs just like peregrines so they’re used to having predators nearby but this is way too close.  I’ve never seen a live pigeon in the peregrines’ nest, so what’s up?  

I have a theory.

Last year the University of Pittsburgh cleaned the Cathedral of Learning and found pigeon nests in every nook and cranny.  When the cleaning was finished they pigeon-proofed the building with netting and spikes.  This spring the pigeons have far fewer places to nest so this pair is desperate enough to try the beautiful nest ledge provided for the peregrines. 

If you click on the pigeon picture you’ll see a slideshow of the pigeon and his lady checking out the area.  They leave abruptly when…    Well, you just have to see the slideshow.