We see a lot of wild birds around Carnegie Mellon.  If I am allowed to stay outside and watch birds all day, I am happy to do it.  (Similarly, if I am told I can stay outside an airport and watch airplanes all day, I am happy to do it, too.)

One of the birds that I like the best among them is Blue Jay.  One of the reasons is, I suppose, the color scheme of this bird is similar to Mitsubishi T-2 Blue Impulse, which was used by the aerobatic team of Japanese Air Self-Defense force until they changed the airplane to Kawasaki T-4.

Blue Jay.  Blue, light blue, white, and black combination.

T-2 Blue Impulse.  Blue, light blue, white, and black combination, with red Japanese symbol.

Blue Jays are tough birds.  When a hawk flies into the territory, a squad of Blue Jays swoops in and mobs a hawk until it retreats.  The way they attack the hawk is impressive.  It dives down, flies less than half an inch back of the hawk (maybe it kicks the hawk in the fly-by), then makes a half-cuban eight to reverse the course, pecks the hawk, and then flies back to a tree branch, a street light, or an electric line.  Even after the hawk takes off, Blue Jays chase the hawk until it really gets out of the territory.  So, a Blue Jay is really a fighter-bomber.  It dominates the sky and is also good at ground attack.

Blue Jays sometimes makes a pre-emptive strike at other birds' nest.  I have witnessed once when a Blue Jay was attacking a nest of a Robin.  But, that time two nests were too close, and they apparently had some dispute.  I also saw a Robin kicking out the Blue Jay a few days before the Blue Jay's raid.  The Robin ended up with losing the battle then.

So, some say a Blue Jay is a mean bird.  Maybe.  But, they are living in a wild life.  They are doing what they need to do to live.  I like Blue Jays' stern and uncompromising attitude of living.  That's the way a wild bird should live.

The population of Blue Jay is nothing threatened.  They adapted to live with humans.  Some say we should stop feeding wild birds because they will forget to live wild if they are used to getting food from human.  I disagree.  They adapted to live with humans.  If humans are gone, they will re-adapt to the human-less environment.  Don't underestimate the strength of the wild birds.

So, Blue Jays are not a special bird at all.  They rather are common backyard birds.  Nonetheless, the population is much smaller than Robins, pigeons, and sparrows.  From my observation, the number of Blue Jays seems to be slightly lower than Cardinals around Carnegie Mellon University and Schenley park.  Of course it is just my impression and nothing scientific.

I was lucky to see a family of Blue Jays growing kids in Flagstaff Hill in 2007.  I was able to watch them until they leave the nest.  It's already four years ago.  In 2008, I saw a pair of Blue Jays building a nest in Flagstaff Hill, but they were not able to hatch their eggs.  Last year, in 2010, I found a nest just outside Scaife Hall.  But the family was struck by a tragedy.  All three baby Blue Jays died for an unknow reason.  I saw dead bodies a day after a severe storm.  The storm might have been the reason.  But, the baby Blue Jays already had a good feather.  It didn't seem to me that the baby died from hypothermia.  They may have died from disease or from some pesticide sprayed over the trees.

This year, I found a nest in Flagstaff Hill.  There was a twist on the day after the young Blue Jays finally left the perimeter of Flagstaff hill.  I really thought one of them was eaten by a hawk.  But, luckily, that was my mistake.  I believe they are now training to be a good flier (as of June 9, 2011).

Below is what I saw over 1.5 months of watching.

4/27

Found a nest.  I saw a Blue Jay when I was walking in Flagstaff Hill, and I followed it to the nest.  This time tree leaves were not so much grown and I was able to see the nest from the distance like 10ft away.  Since I didn't want to scare the birds away, I stayed at least 10ft this time.  My guess was the Blue Jays built a nest while I couldn't walk to CMU due to bad weather in April.  We had so many rainy days in April.  If the nest was built one or two weeks ago, eggs was going to hatch in 10 days or so.

Found a nest.  Horizontal stabilizer of a parent bird is visible.

5/2

The parent bird is patiently brooding the eggs.  The leaves were growing and making difficult to watch the nest from distance away.

An eye of the parent bird is visible.  Can you see?

5/11

Tree leaves finally blocked the horizontal line of sight.  I had to walk in to the bush and look up to see the nest.  The parent bird sometimes looked at me, but didn't seem to care much.

This picture was from 5/10.

5/23

I was able to confirm through the tele-photo lens that at least two baby Blue Jays were born.  But, due to the cloudy weather, I didn't have adequate lighting.  I couldn't take a meaningful picture this time.

5/24

A hurricane-force wind blew through the Pittsburgh last night.  I was worried about the nest, but the parent bird protected their babies well.

Although it is blur, two baby Blue Jays are visible.

A parent bird that brought some food to the babies.  It presumably was a male bird.

Must be the same bird as the above.
This guy may have taken a bath in a water before bringing some food.

5/29

I tried to bend a low branch that was blocking the line of sight, and the parent bird didn't like it and complained me.  I didn't mean that.  Sorry.

I could see only one baby bird in the nest.

I could see only one baby bird in the nest.  I suspected the other one died.  And then...

The other one was on the ground!
One small step for bird!

The other one ones on the ground!  In 2007, it took 12 days after babies are born before they left the nest.  I confirmed the baby birds just a week ago.  It was such an early departure.  In fact, I suspect that the baby bird was already a few days old when I saw them for the first time.  I had to look up from the bush, and couldn't see when the baby bird was smaller.

Tiny horizontal stabilizer of the remaining baby bird is visible.

The one on the ground already had blue wings, which is a signature of Blue Jays.  But, since it was still a baby bird, it was sleepy all the time.  As I was watching, it fell asleep among the fallen leaves.  Well, due to the vivid blue wings, it was clearly visible.  I could see it.  It should have been visible to predators.  I wondered if it was ok for a wild bird.

The baby bird sleeping on the ground, not dead.

5/30

The other baby Blue Jay also left the nest.  The nest was empty.  One of them was sitting on a low branch.  I supposed it was the one left the nest yesterday.  The other one was at the root of a tree.  I guess he (she?) was thinking he was hiding well, although I was able to find him easily.

One of the babies was on the low branch.

A parent bird.

The other one was sleeping at the root of a tree.
This guy may have been thinking he was hiding well.
Actually he was pretty visible...

The one sitting at the tree root often raised its hip when it had to poop.  Even an adult bird does something similar.  It raises a tail a little.  But, this behavior is more visible for a baby bird.  When the baby bird is still in the nest, a parent bird often taps the hip of the baby bird when it raises the hip.  I don't know exactly why the parent do this.  I guess that the baby bird poops easier if the parent taps on the hip.  And, I also saw a baby bird tapping on the hip of the parent bird.  The baby bird may just be mimicking what the parent bird does to the baby bird.  Once I also saw a baby bird tapping on the hip of a parent bird, then raised the hip to poop.  Maybe it was asking the parent to tap on the hip.  It is an interesting behavior of Blue Jays.

A Red-Tailed Hawk landed near the nest later in the afternoon.  It captured a squirrel for dinner.  The joint force of parent Blue Jays and other Robins mobbed it to kick out of the proximity of their nests.  The following picture was a parent Blue Jay ready to attack the hawk.  If you look closely at its bill, it has some insects to be fed to its babies.  So, it was carrying food and mobbing the hawk simultaneously.  As I wrote upfront, the maneuver of the Blue Jay was acrobatic.  In one pass, it dived down to the hawk passed close behind it, then made a half-cuban eight to reverse the course, attacked again, and then returned to the station.  The hawk didn't seem to care though.  It finished eating and then took off to fly away from Flagstaff Hill.

It was mobbing the hawk while carrying some insects for the baby birds.

5/31

One of the baby Blue Jays was sleeping on a branch about 3ft high.  The other one was under a bench.  I guess this guy found that the bench was a good hiding place.  I left my office about 5pm, then saw both two baby birds coming to the same bench.  I saw parent birds coming to the bench over and over again to feed the babies.

A baby Blue Jay sleeping on a branch
dreaming of the sky to conquer

The other one stretching a main wing.

A baby Blue Jay walking on the grass.
It was so visible that I was worried about a predator spotting it.

Both two baby birds climbed up to the same bench.

From a different angle.
It was a rare chance of seeing wild birds sleeping.

A parent and two kids.

6/1

One of the baby birds was sleeping on a branch in the bush.  The other one was under a different bench.  This guy seemed to like a bench.  Through my tele-photo lens, I saw it clutching and opening one of its feet continuously.  Maybe its feet were not strong enough, and this guy was not feeling comfortable.  It was sleeping though.  A person came to and was sitting on the bench several minutes, but the baby Blue Jay didn't seem to care.  I hope it will become friendly to human even after grown up.

A baby Blue Jay almost falling asleep under the bench.

The other one sleeping in the bush.

It stood up, but fell asleep again.

Then there came a lawn mower!  If the baby Blue Jay under the bench hopped into the path, it will become a ground meat!  The biggest threat since its departure from the nest!  But, as long as it was staying under the bench, it was going to ok, I thought.  The baby Blue Jay didn't think that way.  It came out of the bench and started hopping on the grass!  It was trying to jump long distance per hop by flattering the wings.  But, the wings didn't appear to be very effective yet.  Looked like it was trying to get to the bench it was staying yesterday.

But,... before reaching the goal, it got tired and fell asleep in the middle of the field!  Oh!  No!  It's going to be a ground Blue Jay when the lawn mower runs over it.  I really thought about snatching the bird to bring it to a safer place.  But, when I tried to snatch it, this bird refused.  So, I left it there.  It was very difficult to leave it there.  I knew I was going to regret if I later found the bird be ground.  But, I had to go to my office.  I left Flagstaff hill, leaving the baby Blue Jay there sleeping.

There came a lawn mower!

Little Blue Jay on the Prairie

You are not supposed to sleep there!
Wake up!

Two parent birds were flirting.

I was relieved when I found both two baby birds alive.  One of them was staying in the same bush, and the other was sort of hiding on a tree root under leaves.  This guy was not ground by the lawn mower.  The one in the bush was trying to go up to higher branches.  Ambitious bird!  I guessed it was going up to higher branches by tomorrow and would be difficult for me to spot again.

This guy was not ground.

This one was hiding in the bush.

A parent Blue Jay taking a rest.

6/2

Both two baby Blue Jays were sleeping in the same bush.  They were still not too high.  I often saw one of the parent birds were flattering wings just like a baby bird begging for food to the other parent bird.  I didn't know if it was playing or was doing it on purpose.

Two siblings sleeping in the bush.

A baby Robin also just left a nearby nest.

In the later afternoon, I witnessed one of the baby birds successfully jumped from one branch to another.  Parent birds seemed to be encouraging the baby birds to practice jumping across branches.  A parent often came to a higher branch but didn't come down to where the baby birds were.  So, the baby birds had to climb up to the parent's location to get food.

Horizontal stabilizer was growing.

Two baby birds staying close to each other.

6/3

One of the two baby birds, presumably elder one, climbed up to a higher branch.  It was like 10ft high.  The other one didn't seem to be able to go up that high, and was sleeping on a lower branch, like 3ft high.

Presumably younger one.

A parent bird threatening a Robin that came close to the baby Blue Jays.
I guess Robin also just wanted to bring food to its baby bird since it was also close.

The parent Blue Jays were really encouraging baby birds to climb up to higher branches and didn't come down often.  The younger sibling was trying hard, and in the process of climbing up, it passed next to a baby Robin.  It was a rare combination of Blue Jay and Robin babies side by side.

Blue Jay and Robin babies side by side.

Blue Jay came a little higher.

The younger sibling tried to jump up once again, but the attempt was not successful.  It dropped to the ground and had to start over.

Starting over.

The younger sibling may have got frustrated.  It hopped out of the bush toward the grass.  It was not good.  I said to it not to come too far out.  I don't know if it understood what I said, but it decided to jump back to the bush.  This time it was able to jump like 6ft by flattering its wings.  The wings were much more effective than yesterday.

I came back around lunch time, and the younger sibling was also sitting on a branch roughly 6ft high.  They are getting more and more difficult to spot.

Later afternoon, I was able to spot them by tracking a parent bird.  Two young Blue Jays were sitting on a branch roughly 60ft high.  When I spotted them, they were slightly apart.  But, later one of them came to next to the other and they were staying side by side.

They were able to climb up to about 60ft high.

Jump!

It succeeded in jumping to close to the parent.

All family in one picture.  One of the parents is partially hidden by leaves.

I expected that the young Blue Jays would be able to flatter the wings stronger by tomorrow and would climb up to even higher branches.  Then it would have been the last chance to see the baby birds until they come out of the bush for flight training, I thought.

These two Blue Jays were very lucky in terms of weather.  No single rain drop fell to the ground to this day since the departure from the nest.

6/4

I didn't expect to be able to have a visual contact with the young Blue Jays.  Nonetheless I went to Flagstaff Hill in the late afternoon anyway.  To my surprise, I could hear the voice of young Blue Jays from high in a tree.  I looked up and was able to find one.  The other one was on a nearby branch, but it jumped to another branch that was hidden by leaves.  It was good to confirm two young birds was growing.  The forecast for the night was predicting scattered thunderstorm.  The young Blue Jays will be soaked for the first time without being covered by a parent bird.  But, they must have grown enough feather to avoid hypothermia by now.  Rather, I was worried if they are not blown away by strong wind.

A parent Blue Jay was cracking a nut for the young birds.

One of the siblings in sight.

The other one was on a nearby branch.

6/5

I was supposed to fly to Reading (KRDG) airport to see an air show with my pilot friends.  The weather at Pittsburgh was good.  But, Johnstown (KJST) was reporting IMC (Instrument Meteorological Condition=low visibility and/or low cloud).  And, the airplane we were going to use was not qualified to fly into instrument condition.  We had to cancel the flight.  Instead, I walked to Flagstaff hill around noon.  I was hoping to confirm that two young Blue Jays survived the storm in the last night.  But, I also was expecting that the two young birds must be even higher and more difficult to spot.

As I expected, I couldn't find them although I could hear voice of the young birds asking for food.  They were somewhere on a high branch.  I tried to follow a parent bird and finally found two young Blue Jays sitting on a branch side by side.  They must be ready to start flight training.  They are comfortable staying high and they are able to jump one branch to another.  Next step is flying longer distance.

They are climbing higher and higher day by day.

The timeline of this Blue Jay family was so much different from the one I watched four years ago.  In 2007, all baby birds left the nest on 6/5.  I could see one bird hopping on the grass 6/7, but all of the baby birds climbed up to the high branch in the afternoon of the same day.  This year, two baby birds was staying close to the ground for four days, double the amount.  I can only imagine what made this difference, but maybe because the family of year 2007 built their nest slightly away from the road, and they didn't feel immediate threat that made parents decide to let the baby birds leave the nest early.  I was lucky this year because I could see baby Blue Jays closely for four days.

6/6

I spent about 30 minutes in Flagstaff hill to write a paper.  I saw a parent Blue Jay flying toward the bush behind Scaife Hall.  But, I couldn't spot young Blue Jays.  When I closed my laptop and walked to my office, I found them.  I heard the voice of young Blue Jays from a tree next to Scaife Hall.  The young Blue Jays for the first time left the perimeter of Flagstaff Hill.  I looked up and saw two parents and two young Blue Jays.  They are close family.

Blue Jay seems to care about the family tie.  I have seen many time two adult Blue Jays flying with two to four young Blue Jays in a flock.  I was wondering if they were a family or just an unrelated Blue Jays that happened to be in a flock.  But, according to Wikipedia, a Blue Jay mates with a same partner for the life, and the parent birds typically stays together with the child birds until early fall.  I wished the four birds stay together until the young Blue Jays are independent.

The young Blue Jays gone beyond Flagstaff hill.

I came back to the same tree in the late afternoon after work.  But, they were no longer there.  I suppose they moved into the bush.  The distance that the two young birds moved for the last 24 hours was a lot longer than before.  Now they are capable of moving long distance.  I was looking forward to seeing two parent Blue Jays with two young birds flying together around Carnegie Mellon.

The article on Wikipedia also suggests that Blue Jay can mimic human voice.  I should have tried to teach some words to the baby birds when I could come close.

6/7 Grim discovery

The story of the Blue Jay family should have ended there.  I was thinking the baby Blue Jays were most vulnerable while they were not able to go up to high branches.  When they were capable of climbing up to high branch and jump from tree to tree, I thought they were safe.  But, the nature's law was not on their side.

I came to CMU around 8:30 for a meeting, and found feathers scattered around.  A bird must have been eaten by a hawk.  Initial thought was a pigeon was caught by a hawk.  But, as I looked at the feathers closer, it had a signature of a Blue Jay.  The feather had white tip, and a black band was separating a blue-gray part near the root.  The young bird must have started flight training and was flying after the parents.  But, the hawk didn't miss a young Blue Jay that was not agile as an adult bird.

When I found the crime scene, everything was over.  My prime suspect is a Red Tailed Hawk, but there was no way of concluding.  Also I couldn't tell if it was really from the young bird or a parent bird that tried to save the child.  But, it is so unlikely that an adult Blue Jay is caught by a hawk.  And, I couldn't find a long tail feather with black stripes.  If the feathers were from an adult Blue Jay, I should see at least one or two of such feathers.  Some feathers were long like an adult bird, but from the pictures, main wing of the young Blue Jays must have grown like an adult by then.  What they didn't have were long horizontal stabilizer (I mean, tail wing.)  Also, the scattered feathers didn't show clear black stripes.  According to the following web site,

http://www.wbu.com/chipperwoods/index.htm

Black stripes become clearer with age.  An adult bird has clearer stripes than a young bird.  From these observation, I concluded that one of the young birds were eaten by a hawk.

Why Blue Jay?  There were so many pigeons, robins, and squirrels.  Why this hawk chose to pick a young Blue Jay?  I wanted to see a family of four flying close together over Flagstaff hill.  They were close family.  It made me so sad to see one missing from the family.

It looked like one of the baby Blue Jays in the pictures was no longer with us.  I prayed repose of the lost Blue Jay.  That bird was almost ready to take to the sky.  I wished the bird's short life was a happy one.

6/8 Or, was the victim really a Blue Jay?

One day after the apparent loss of a young Blue Jay.  I couldn't find young birds any more.  Actually, there were too many Robins and European Starlings.  Their voice were overwhelming and I couldn't here voice of Blue Jays there.

But, I had a serious doubt about whether the victim of the bird murder yesterday was really a Blue Jay.  I knew the vivid blue color of the Blue Jay is from light refraction.  The wing material itself is not blue.  If I crush the wing, it loses the color.  I knew that.  But, the feather from the yesterday's crime scene (Don't get me wrong.  I like hawks, too) didn't appear blue enough no matter what angle I hold against a light source.  A hawk doesn't crush the wing while it eats a victim.  The wing should preserve the structure that makes signature blue of a Blue Jay if it was really from a Blue Jay.

Also, the white tip was too large to be a Blue Jay's.  The left two feathers in the following picture is really from a Blue Jay.  A bird dropped them when it flew away.  I believe these two were from different Blue Jays.  Most likely the one far left was of a main wing, and the second from the left was of a horizontal stabilizer (again I mean tail wing.)  The right three feathers are from the crime scene.  The left most feather, of a Blue Jay, has a white tip, but it is covers only tiny length, like 1/8 of the feather.  The middle one and the right most one, has a long white tip.  It covers like 1/3 to 1/4 of the length of the wing.  Also, the boundary between the white tip and the rest part is straight in the Blue Jay's feather, and curved in the feathers from the crime scene.

If you look at the left two feathers closely, you can see black stripes.  Although the stripes of a young bird may not be clear, from some pictures, the young birds already had some black stripes.  But, the feathers from the crime scene had absolutely no stripe.  Only a black band.  I also checked some more pictures of the crime scene that I took with my iPod touch, but none had black stripes.

And, the clear-ness of the black part is also different.  The black stripes of a Blue Jay feathers are visible, but not so clear.  But, the black part of the crime-scene feathers are clear and lying between the white tip and blue-gray part.

The shape of the feathers are also different.  The Blue Jay's feather from a main wing is a tapered shape with narrow root and wider tip.  But, the feathers from the crime scene is wider root and narrower tip.

The left two are of a Blue Jay, and the rest from the crime scene.

Other crime-scene photos.
Can anyone identify the victim's identity?

This photo confirms that a young Blue Jay already had a black stripes.

From these observations, I concluded that the victim was not really a Blue Jay.  The new question is what it was.  The reason why I initially thought the feathers were of a Blue Jay was because I don't see any other bird around Carnegie Mellon that has blue-gray root and white tip separated by a black band.  I flipped through the book "Birds of Pennsylvania" from the first page to the last page, but I didn't find any bird that matches this pattern.  Pigeon? Maybe.  Pigeons are hawk's favorite nutrition source.  But, I don't remember any pigeon with this beautiful feather with white tip.  Now the victim's identity is a mystery.

I was nearly depressed when I thought one of the Blue Jays were gone.  But, the conclusion from my crime-scene investigation lightened myself.

6/9

Two young Blue Jays seemed to be ok.  I followed a parent Blue Jay, and heard one voice of a young bird asking for food from a high branch and the other voice from near the ground.  I couldn't have visual confirmation, but I guess they were well and growing.