Monthly Archives: July 2011

Swarms


Have you ever had a cloud of bugs fly around your head, yet when you wave them away they’re back in an instant?  The bugs aren’t biting but they will not leave.  What’s going on?

It’s a mating ritual.

In some insect species the winged adults congregate in a swarm to meet each other.  It’s the bug version of the bar scene.

Each bug flies around in the crowd, looking for a member of the opposite sex.  The individuals break away to go off and mate yet the cloud stays put.  To do this they use a tall object as a reference point — a swarm marker — to maintain their position.  We see this in the fall with flying ants at hawk watches.  The mountain is their marker.

Anything can be a swarm marker.  In early June, thousands of mayflies swarm at Lake Erie in Cleveland using buildings, people and trees as their markers.  They look scary but they’re harmless — and messy when they leave the swarm to mate on windows, walls, cars … everything!

So it’s not that the bugs love you.  It’s just that they’re using your head as a swarm marker.  Walk under a tree with low branches and they’ll leave your head to use the tree.  Good luck leaving them behind when you walk away.

Of course, this doesn’t work with mosquitoes.  Mosquitoes do love you!

(photo by Anton Gvozdikov/Shutterstock.com)

p.s. For more information about midge swarms, see page 9 of this document from Nature.org.

Does Half a Degree Matter?

10 July 2011

On July 1 NOAA’s National Climatic Data Center released the new U.S. Climate Normals based on 1981-2010 data.

“Normals” are a 30-year average of daily and monthly temperatures, precipitation, snowfall, snow depth, and heating and cooling degree days.  We hear them every day when the weather forecast is compared to normal and they’re used to forecast energy loads, crop planting times and construction schedules, to name a few.

Every ten years NOAA recalculates the normals using an international protocol that drops the oldest decade and incorporates the most recent.   On July 1, the 1970s were dropped and the 2000s included.

The result shows that the average U.S. temperature increased half a degree.   2001-2010 was the hottest decade on record  — 1.5oF hotter than the 1970s — but the normals are a three-decade average so it comes to 0.5oF.   Surprisingly, most of the temperature gain was through warmer nights, not hotter days.  January minimum temperatures rose 5 degrees in the most northern U.S. states.

Does that half a degree matter?

Indeed it does.   Warmer nights mean that killing frosts start later in the fall and end earlier in the spring.  Wherever you live, the growing season is a little bit longer.

You can see this on the NOAA map above where each colored stripe represents the change in a plant hardiness zone.  Pittsburgh is squarely inside Zone 6 so we aren’t in a colored stripe — yet — but northwestern Pennsylvania and the Allegheny Plateau have warmed enough to move from Zone 5 into 6.   Michigan changed a lot!

You might think this is great news but there are bad side effects.  If you rely on plants at the southern edge of their range, those plants are stressed because it’s too hot for them.  Even if you hate winter, you’ve got to admit it’s a great pest control system. Deep freezing nights protect our plants by killing many insect pests.  Sadly, pine bark beetles now thrive in Colorado and Canada because their winters are no longer cold enough to kill them.

If you’ve been gardening or farming for the past 30 years you’ve noticed the shift in temperature and you’ll be glad to know that USDA is revising their 1990 Plant Hardiness Map based on the new data.

When the new map comes out, keep it handy — but expect to need a new one in only 10 years.  According to NOAA’s Climate Center, plant zones will shift dramatically by 2041.  By then Pittsburgh will feel like Tennessee.  We’ll be in Zone 7.

Click on the map above to read Plants (and Pests) Respond to Warmer Nights and to see larger versions of the range maps.

(The image above is NOAA Climate Services‘ map of plant zone changes based on 1981-2010 U.S. Climate Normals.  Click on the map to see the original.)

Subtle Beauty


Sparrows are stripey, brown, boring little birds … right?

Not when you look closely.

Last weekend I saw Henslow’s sparrows at Piney Tract and because they were Life Birds I spent time looking carefully at each one.

At first they were confusing brown birds whose only distinguishing feature were their flat-topped heads and “Roman nose” beaks.  But then one paused on top of a bush with the light just right. 

His head and neck were washed in olive.  His wings were pale chestnut.  In that moment he was incredibly colorful.

Sparrows have a subtle beauty.  It just takes time to see.

(Henslow’s sparrow photo taken at Piney Tract last Saturday by Steve Gosser)

Attitude

Bull elk, Benezette, PA, July 2011 (photo by Paul Staniszewski)

8 July 2011

Is this massive bull elk curious?  Challenging?  Or is he just saying, “Welcome to Benezette?”

When European settlers came to North America, elk (also called wapiti) ranged in the eastern U.S. from northern New York to central Georgia but we cleared the forest and hunted the elk, reducing their habitat and numbers until Pennsylvania’s last native herd died out by 1877.

In 1913 the Game Commission reintroduced elk from the Rocky Mountains to their last known location in north central Pennsylvania.  The herd, now centered in Benezette, Elk County, remained small until the late 20th century.  Since then they’ve expanded in Cameron, Clearfield, Clinton and Centre counties as well.

Elk prefer forest edges and open meadows.  In summer they eat grass and flowering plants; in winter, leaves, bark and twigs.

These animals are huge.  The males are 25% larger than the females and can weigh up to 1,100 pounds.  They stand 50-60 inches tall at the shoulder and their antlers can span five feet.  This headgear is heavy, up to 25 pounds.

Bulls grow new antlers every year.  They shed them in February and March and begin to regrow them immediately up to an inch per day.  To give you a sense of this rapid growth, these antlers are only four to five months old.  Wow!

Right now the elk herd is dispersed.  The cows went off alone in June to give birth to their single calves.  The males, meanwhile, are wandering and grazing.  The herd will meet up in the fall for the breeding season, called the rut.

If you want to see Pennsylvania’s elk herd, plan a trip to Benezette in September or October when the bulls will be bellowing and jousting to see who can claim the most and best cows.

Will you see this particular bull when you go?  If you do, don’t get this close!   He’s going to be in a fractious mood.

Paul Staniszewski, who took this photo, saw him only two days ago in Benezette.  Paul has years of experience photographing elk and even he was surprised by this close approach.  As he says, “I have been trying to photograph an elusive bull elk known locally as “Attitude” and I finally got an opportunity yesterday [July 6].  I was about 20 feet away when I snapped this photo and he continued to walk toward me to about 5 feet away.  I could have touched him… Scary stuff… “

As Paul said, “You can see in his face why they call him “Attitude.”

(photo by Paul Staniszewski)

Theories

One incident is unfortunate.  Two is a pattern. 

After one young peregrine died on Monday in this hall of mirrors and a second was injured yesterday, my brain has been working overtime trying to make sense of it all. 

Why were there no peregrine deaths in Oakland during the first five years of nesting but at least one per year since then?   What caused this?  What changed?

From the start of Pitt peregrine nesting in 2002 through the spring of 2007, only one youngster had an accident in Oakland and it didn’t kill him.  Crash hit a window on the Cathedral of Learning, fell into an architectural nook where he was trapped overnight, and was found in the street the next evening with a broken collar bone.  He went to rehab and was released successfully the following February.  (He actually released himself.)

Since 2008 the news has been bad.  Every year at least one juvenile peregrine has died near Fifth Avenue and Craig Street.  In 2008 Sky hit the windows of the Rand Building.  In 2009 a juvenile died in the Webster Hall chimney but wasn’t discovered until October.  In 2010 one juvenile died and another was injured in that same chimney (which was covered immediately).  This year Yellow Girl died and Red was injured hitting the Software Engineering Institute’s windows on Henry Street. 

What is going on?  Why do the juveniles spend time where it’s so deadly? 

My friend Karen Lang has an answer. 

In the spring and summer of 2007 the University of Pittsburgh cleaned the Cathedral of Learning.  Up to that point the building was a pigeon palace with nests in every nook and cranny.  At the end of the cleaning project the building was pigeon-proofed with netting to cover the access points.  With few pigeons at home our juvenile peregrines learn to hunt at the next nearest flock which happens to be at Fifth & Craig.  That area is a much more dangerous zone than the Cathedral of Learning because of its now-covered chimney and two mirror-glass buildings.  

Slowly, we humans are figuring this out.  The chimney was easy to fix.  The windows are harder.  

It would help if the pigeon flock moved to a safer location.

(photo of the Software Engineering Institute hall of mirrors on Henry Street by Kate St. John)

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Update on Red’s condition:  This morning I saw “Red” eating breakfast on Heinz Chapel steeple while both of his parents watched him.  Like all parents they could tell he wasn’t well and needed some extra attention.  Over at St. Paul’s Cathedral steeple, one of his remaining sisters whined.  She seems fine.  I hope she stays away from those windows!

Oh No! Red Hit Those Windows Too!


At 9:30am I got a phone call from Bill Powers that he’d heard a peregrine had fallen on Henry Street, another victim of the Software Engineering Institute windows.

I couldn’t believe it!  Was this an old report about Yellow?   Could a second young peregrine have crashed in the same place so soon?

After several phone calls we determined this was a new accident so I ran to Henry Street with my bird-rescue towel, calling the PA Game Commission’s Beth Fife as I ran.

Fortunately by the time I got there, Red had flown.  Eyewitnesses say he was standing stunned on Henry Street behind SEI where the mirrored office building and mirrored garage are connected by a mirrored second floor walkway.  His imprint was on the walkway glass.  Pigeons circled overhead, reflecting in the glass a thousand ways.

I called Beth again to let her know the bird had flown.  She said he was probably perched somewhere gathering his wits.  I walked back to work, looking for Red on the ground and on low buildings.  Eventually I found him perched on a building three blocks from the scene.

Beth assured me this is good news.  He can fly.  He can see well enough to navigate.  He can perch.  He just needs some quiet time to recover.

Oh, how I hope he recovers completely and stays away from Henry Street!

Meanwhile, let’s work with CMU to correct that hall of mirrors at SEI.  It’s a prime opportunity for bird-friendly redesign.

(photo of Red from about a month ago, taken in early June by Nancy Weixel)

 

p.s. This incident earned “Red” a real name.  Karen Lang named him Henry because his accident happened on Henry Street.

Milkweed of the Woods


We think of milkweeds as sun-loving plants so it was surprising to find this species deep in the woods in the Laurel Highlands.

Poke Milkweed (Asclepias exaltata) would not have caught my attention that day if it hadn’t been in bloom.  The flowers are a pale version of Common Milkweed with fewer flowers per cluster on long drooping stems.  In deep shade they look like lazy, ghostly starbursts. 

The species name exaltata means the plant is tall.  My specimen was over three feet high though they can grow as tall as six feet.

You’ll find this sweet-smelling flower in woods and at woodland edges from Ontario to Mississippi. 

(photo by Dianne Machesney)

Sad News

Kathy Borland was doing rounds today (July 4) as a security guard for CMU when she heard there was a dead hawk on Henry Street behind the Software Engineering Institute.  When she got there she found it was a peregrine, one of Dorothy and E2’s brood who hatched this spring at the Cathedral of Learning.

Kathy got in touch with me, I got in touch with the PA Game Commission’s Beth Fife and then I went to see the bird.

It was “Yellow Girl,” the one we saw so close on Heinz Chapel on June 6

“Yellow Girl” apparently hit a window on SEI around 1:15pm with so much force that it completely broke her neck.  Kathy found her face down on Henry Street with her wings spread.  She probably died instantly.

Poor Yellow didn’t know what hit her.  She may have been chasing pigeons and thought the window was the sky.  Alas.  There was nothing we could do. 

As I said before, if you want to save birds do something about windows!  

Windows kill.

(photo of deceased juvenile peregrine “Yellow,” black/green, 72/AE, by Kate St. John)

A Good Time to be a Bald Eagle


Just in time for the Fourth of July, the Game Commission reports that our national bird is doing quite well in Pennsylvania. 

There are now 203 nesting pairs in the state including, for the first time, a successful nest in Allegheny County.   That eaglet is predicted to fledge this weekend from his home near Dashields Dam.

This is great news since the time 30 years ago when eagles were endangered due to DDT.  

If you want to see eagles today you have a lot more places to choose from.  You can always see them at Pymantuning and now they breed along the Allegheny and Clarion Rivers.  (Here’s a county-by-county nesting map.)

Take a lawn chair or a kayak, maybe do some fishing to pass the time.  If you’re in good eagle habitat, both you and the eagle will catch a fish.

Happy Fourth!

(photo by Kim Steininger)

Feed Your Nestcam Addiction


The peregrines have flown and the eagles have fledged.  Most of the raptors are gone from the webcams but you don’t have to go through withdrawal.  You can still watch wild birds online.

Cornell Lab of Ornithology’s Nestcams website has many live webcams to choose from.  There are barn owls, bluebirds, wood ducks and even seabirds.  They also have archives from prior years.

Right now the chimney swifts in Glenham, New York are particularly busy.  They just hatched three fluffy white chicks on June 30. 

Click on the screenshot above to watch them.  Be patient.  It takes a while for the black square to become a video.  (I had better luck with Internet Explorer than with Firefox.)

When it’s hot outdoors, stay inside and feed your nestcam addiction.

(screenshot of chimney swifts from Cornell Lab of Ornithology NestCams)