Archive for the 'Bird Behavior' Category

May 20 2016

The Blue Jay’s Courtship Sounds

Blue jays are making interesting sounds and gestures lately but what do they mean?

In the spring I often hear blue jays say “tweedle” and, on rare occasions, I see one bounce and gurgle.

Tweedle? Gurgle?  Lesley the Bird Nerd explains it all in this 4-minute video.

 

(video by Lesley the Bird Nerd on YouTube)

 

 

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May 18 2016

More Robins, Fewer White-throated Sparrows

American robin, white-throated sparrow (photos by Marcy Cunkelman)

American robin, white-throated sparrow (photos by Marcy Cunkelman)

We humans are starting to respond to climate change. The birds already have.

In a study on two continents — North America and Europe — data from 1980 to 2010 shows that populations of our common birds have been affected by climate change and the gap is growing.  Bird species expected to do well due to climate change have substantially outperformed those expected to do badly over the 30 year period.  It’s the first real demonstration that climate is having a similar, large-scale influence on the abundance of common birds in widely separated parts of the world.(*)

Here are two examples from North America:

American robins are an adaptable species whose range has expanded as the climate warms.  Robins don’t have to go as far south in the winter and now they breed in Alaska!

White-throated sparrows are a common winter species in the Lower 48 but when it comes time to breed they’ll be in trouble.  As they move north the forest they require for breeding gives way to treeless landscapes.  It takes decades to grow a forest and climate is changing faster than the plants can catch up.  White-throated sparrows are losing ground.  Click here to see their changing map.

More robins, fewer white-throated sparrows.  The populations of common birds are affected by climate change.

Read more about the study here in Science Daily(*).  See Audubon’s climate website for details on North American birds.

 

(photos by Marcy Cunkelman)

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May 17 2016

Peregrine Sounds: What Do They Mean?

Peregrine shouting in flight (photo by Chad+Chris Saladin)

Peregrine shouting in flight (photo by Chad+Chris Saladin)

When you hear peregrine sounds on the nestcam, what do they mean?

Click here for a new Peregrine FAQ that explains peregrine vocalizations.

 

(photo by Chad+Chris Saladin)

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May 05 2016

Stuck In The Mirror

Published by under Bird Behavior

Robin fighting his reflection (photo by Charlie Hickey)

Robin fighting his reflection (photo by Charlie Hickey)

On Throw Back Thursday:

This is the time of year when birds go mad and fight with car mirrors and windows. They don’t realize that the angry bird who won’t back down is a reflection of themselves.

Though some birds become obsessed with particular locations it’s a temporary problem while they’re establishing their territory.  Unfortunately the obsession could last for weeks!

If you’ve got a problem bird, cover the reflection for a few days so the bird can’t see itself.  Your car will look funny with plastic grocery bags on the side mirrors but the bird will give up.  Massachusetts Audubon has some helpful tips.

In 2013, this robin wasted a lot of time fighting his “challenger” on Charlie Hickey’s front door in: Tapping At My Chamber Door.

 

(photos by Charlie Hickey)

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Apr 27 2016

Don’t Play It Again, Sam

Black and white warbler, singing (photo by Chuck Tague)

Black and white warbler, singing (photo by Chuck Tague)

Spring migration is ramping up. Every day there are new birds to see and hear in western Pennsylvania.

What if you hear a really good bird and can’t see it?  Should you playback its song on your smartphone to lure it in? Please restrain yourself. Here’s why.

Although birders debate the use of playback, the Code of Birding Ethics is clear:

To avoid stressing birds or exposing them to danger, exercise restraint and caution during observation, photography, sound recording, or filming.

Limit the use of recordings and other methods of attracting birds, and never use such methods in heavily birded areas, or for attracting any species that is Threatened, Endangered, or of Special Concern, or is rare in your local area.    —  American Birding Association Code of Ethics

In other words, our first priority should be the birds’ welfare.

Song playback is like this to a bird:  Imagine you’re at home having dinner and someone knocks on your front door.  You drop what you’re doing and go answer it.  There’s no one there, yet you keep hearing them knock over and over again.  Of course this is upsetting.  (People stop “answering the door” much sooner than birds do.)

David Sibley, whose app makes playback very easy, compares the proper use of playback to fishing.  The most successful technique barely plays the song at all.  Read how to do it here.

I once witnessed a clear example of what we should never do.

Prothonotary warbler (photo by Chuck Tague)

Prothonotary warbler, singing (photo by Chuck Tague)

In May 2010 I was thrilled to see a beautiful male prothonotary warbler at Magee Marsh boardwalk in Oak Harbor, Ohio.  The bird was there all day, every day.  He was on territory.  He had a nest hole.

One afternoon I stopped for my second view of the warbler and I saw a photographer set his iPod on the boardwalk railing. Then I heard the prothonotary sing four times.  Several birders looked around. It took us a while to realize the song came from the iPod.

The crowd at the boardwalk was huge and there were many iPods and smartphones in that crowd.  How many times that day! that weekend!  that week!  was the prothonotary warbler challenged on his own territory by a recorded song?

I wish I’d been brave enough to speak to that photographer. I regret it to this day.

Don’t play it again, Sam!

 

(photos by Chuck Tague)

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Apr 26 2016

Did You Know That I Sing?

Female northern cardinal (photo by Steve Gosser)

Female northern cardinal (photo by Steve Gosser)

Now every morning we awake to birdsong.  All the singers are male, right?  Well … not really.

When I took a class on birdsong years ago I learned that female birds don’t sing. This information came from centuries of bird observations made in Europe and North America. Charles Darwin even used it to describe how song evolved in male birds to attract mates and compete for territory.

But in 2014 that “fact” was turned upside down.  71% of female songbirds do sing.  It’s just that most of them are tropical species.  No one had studied birdsong worldwide until a team lead by Karan Odom of University of Maryland, Baltimore County published their findings in Nature Communications in March 2014.

It’s true that almost all the singing birds in North America are male, but there are some exceptions.

Did you know that female northern cardinals (Cardinalis cardinalis) sing and they’re just as good at it as the males?

I was reminded of this last week when a female flew into a tree just over my head and sang a long sustained vibrato even faster than this:

Cardinal couples countersing to synchronize their pair bond.  Yesterday in Schenley Park I saw a female sing a phrase several times, then her mate matched it.

So when you hear a cardinal singing, take the time to find the singer.  It may be a lady!

 

p.s. Female rose-breasted grosbeaks (Pheucticus ludovicianus) and black-headed grosbeaks (Pheucticus melanocephalus) sing, too.  They’re in the Cardinal Family.

(photo by Steve Gosser)

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Apr 15 2016

Raven Solves A Problem

 

Common ravens (Corvus corax) are known for their intelligence and problem solving abilities.

This one solved his own problem, though he created trouble for humans and dogs in the process.  😉

 

(video from The Raven Diaries on YouTube)

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Apr 12 2016

Pigeons Have A Favorite Foot

Rock pigeon hopping down a step (photo by Pimthida via Flickr, Creative Commons license)

Rock pigeon hopping down a step (photo by Pimthida via Flickr, Creative Commons license)

 

Most of us have a dominant hand that’s our favorite choice for everything that requires skill.  About 90% of us are right-handed.

Did you know that pigeons (Columba livia) have a favorite foot?  And that most of them are right-footed?

This was discovered by Harvey I. Fisher at Southern Illinois University in the mid 1950’s while he was looking for something else.  In 1954-1955 he was studying the landing force that pigeons exert on a perch, so he recorded the actions of 11 pigeons landing a total of 4,000 times.

That’s when he noticed that most of them extended one foot and landed on it first, and that they had a favorite foot for doing this.  He ran more experiments, tallying 7,259 landings.

Seven of the 11 pigeons were right-footed, three were left-footed and one didn’t have a favorite.  That’s about 63% right-footedness.  Read more here in his 1957 article: Footedness in Domestic Pigeons.

I found out this interesting factlet at the Urban Wildlife Guide’s Right-footed Pigeons, and was so intrigued that I bought the book: Field Guide to Urban Wildlife by Julie Feinstein. (I highly recommend it by the way.)

So what do you think?  Is this pigeon left-footed?  Or is he just tucking his right foot so it doesn’t hit the step?

 

(photo by Pimthida via Flickr, CC BY-NC-ND 2.0 license. Click on the image to see the original)

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Apr 08 2016

Juvenile Female Makes Brief Intrusion at Pitt Nest

Juvenile female bows to Terzo at Pitt peregrine nest, 8 April 2016, 3:13pm (photo from National Aviary falconcam at Univ of Pittsburgh)

Juvenile female bows to Terzo at Pitt peregrine nest, 8 April 2016, 3:13pm (photo from National Aviary falconcam at Univ of Pittsburgh)

This afternoon webcam viewers were surprised to see a brown-colored falcon arrive at the Pitt peregrine nest and then bow and e-chup at Terzo as he was incubating.

Terzo was surprised, too.  He got up off the eggs and flew away leaving this juvenile, unbanded female to pause for a heartbeat … and then fly away as well.

Click here for the archived footage: Juvenile female visits the nest.

Juvenile unbanded female at Pitt peregrine nest, pausing before she leaves (photo from National Aviary falconcam at Univ of Pittsburgh)

Juvenile unbanded female at Pitt peregrine nest, pausing before she leaves (photo from National Aviary falconcam at Univ of Pittsburgh)

4 minutes later Terzo returned to the eggs.

40 minutes later Hope returned to incubate.

I’ve not had time to review all the footage but so far the archives show no sights or sounds of a fight with Hope.  Apparently Hope chased off this juvenile intruder.

For now, all is calm.

 

p.s. Thanks to Zack and sheba50 for pointing out this brief intrusion.  It was so brief that at first I couldn’t find any evidence of it.  I had to review a lot of footage to find it!

(photos from the National Aviary falconcam at Univ of Pittsburgh)

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Mar 19 2016

Based On Behavior

Hope sitting on eggs, 19 March 2016, 7:43am, temperature 34 degrees F (photo from the National Aviary falconcam at Univ of Pittsburgh)

Hope sitting on eggs, 19 March 2016, 7:43am, temperature 34 degrees F (photo from the National Aviary falconcam at Univ of Pittsburgh)

We humans have been speculating about the peregrine falcons at the Cathedral of Learning — about E2’s death and Hope’s future — but the only way to figure out what’s really going on is to watch the birds’ behavior and write down the facts without speculation.

Using the facts, we can match what we see to typical species behavior and arrive at a general answer.  Long-time observers may also match facts to years of observing the individual birds, providing a specific answer based on the individual’s “personality.”  However, additional data may contradict our conclusions.  We must remain open to changing our minds. That’s how we learn.

Today I’ll tell you what I’ve seen at the Cathedral of Learning and will do some matching based on 15 years of watching the peregrines at Pitt and 8.5 years of knowing E2 as an individual.  Keep in mind that conclusions are always speculation, even though educated by long experience.

FACTS:

  • E2’s death and activities surrounding it:
    • E2’s last appearance on camera was at 12:37pm on Tuesday March 15.
    • Hope laid her second egg at 5:08pm on Tuesday March 15.
    • E2 always visited each egg as it was laid.  He did not visit Hope’s second egg.
    • E2 always brought food to his mates at dawn.  He has not been present at dawn since Tuesday March 15.
    • E2’s body was found on Wednesday March 16, perhaps at 4:00pm–5:00pm.  It was retrieved around 6:00pm.
    • E2’s body has a broken right wing and broken right leg and blood in mouth.  Blood in mouth indicates internal injuries.
    • When E2’s body was retrieved his wings could be opened, therefore no rigor mortis. Rigor mortis is temporary.  I am awaiting further data but the Backyard Chickens website says it sets in half an hour to 4 hours after death and ends 24-48 hours after death.  (Thank you, Donna Memon, for this link.)
  • Hope’s activities since E2 disappeared:
    • She has stayed close to the nest and laid a third egg.
    • This morning’s temperature dropped to 34 degrees F.  Under these circumstances peregrines cover their eggs to keep them from getting too cold.
    • Hope covered the eggs last night.
    • Yesterday afternoon when Hope was not on camera she was not at the Cathedral of Learning.  (I did not see her fly.)
  • Is Hope alone? Is there a new male present?
    • A second peregrine has not been seen on camera since E2’s last appearance.  An intruder male would begin courting immediately. There has been no courting at all.
    • Yesterday afternoon I observed off and on for 90 minutes from the ground at the Cathedral of Learning.  I never saw two birds — only Hope.
    • Hope and E2 were loud when they were near each other, lots of ee-chupping and calling.  I have not reviewed all of the audio archives but from what I have heard… there has been no peregrine noise since E2 disappeared.  (This may need to be corrected if additional data contradicts it.)

CONCLUSIONS (SPECULATION!) ABOUT WHAT HAS HAPPENED:

  • Time of E2’s death: My conclusion, based on knowing him as an individual, is that he died on Tuesday afternoon before 5:00pm.
  • Cause of E2’s death: Based on description of his injuries, my conclusion is that he was hit broadside by something much larger than him.  These massive injuries cannot be inflicted by another bird.
  • Underlying cause of E2’s death: This is speculation on top of speculation!   My guess is that he was hit by a vehicle while swooping low over the road.  (I once saw him swoop low over Forbes Avenue. This 1 observation in 8.5 years merely means he was willing to swoop low over a road at one point.)
  • Did an intruder force E2 into a fight?  No. If an intruder had been involved, that intruder would be at the Cathedral of Learning and courting with Hope by now.
  • Is Hope incubating?  I don’t know Hope’s ways like I knew Dorothy’s so I don’t know.  I would have answered that question based on her continuous time on the eggs but Hope cannot incubate continuously because she must hunt for herself.
  • Is Hope hunting for her own food?  I don’t know.  I have not observed long enough on the ground.
  • Is there a new male at the site yet?   Not that we know of.

As I said above, conclusions are always speculation.

Keep watching and learning.

 

(photo from the National Aviary falconcam at Univ. of Pittsburgh)

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