Archive for the 'Musings & News' Category

Nov 13 2013

Give Back, Get Back

Chidham Point, West Sussex, UK (photo from Wikimedia Commons)

Breach an earthwork like the one above, give back land to the sea, and you’ll get fewer floods.

After Hurricanes Katrina and Sandy, U.S. emergency managers and town planners are discussing giving back land to the ocean as a way to protect still-viable coastal communities.  It’s a concept called “managed retreat,” a name that conjures loss and sometimes sparks defiance in those who live at the ocean’s door.

In the U.K. they’ve recently returned more than 450 acres to the sea by breaching an earthwork just five miles from this one at Chidham Point.  The locals are excited about it.  They expect the resulting salt marsh to increase tourism.  Here’s how:

At Medmerry on the south coast of England, shingle(*) sea walls were supposed to protect towns and undeveloped land but in recent years have proved inadequate.  Stronger storms and higher tides frequently flooded the low-lying communities, especially the caravan (campers) vacation parks.  Some sections of Selsey and Bracklesham Bay are below sea level.  It wasn’t working.

In 2011 the U.K.’s Environment Agency began a managed retreat project in West Sussex.  They built four miles of new sea walls up to a mile inland around the developed areas.  They also built drainage ditches and ponds, two parking lots for visitors, and 10km of bicycle paths and horse trails.  Then they breached the earthworks and gave land back to the sea.  The resulting salt marsh buffers the ocean’s rage.

It’s also great for wildlife.  Even while construction was underway migrating water birds stopped by to visit the growing new salt marsh.  Bird watching improved immediately and is expected to get even better in the months and years ahead.  The new salt marsh will be a birding tourist destination.

Give back to the sea and get back safety and tourism.  Compromise with Mother Nature is good.

Read more about this project and see a video here at the BBC News.

 

(photo of dike at Chidham Point, West Sussex, UK, located about 5 miles from Medmerry)

(*) The British word “shingle” means the sand, pebbles, cobbles and shell-pieces that make up the beach.

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Oct 14 2013

Before Columbus’ Day

Statue of Christopher Columbus by Frank Vittor, Schenley Park, Pittsburgh PA (photo by Piotrus via Wikimedia Commons)

When I learned American history in grade school, Christopher Columbus’ arrival on October 12, 1492 was Day One.  So little was said of the people and habitat that preceded his landing that it seemed nothing happened until he got here.  I learned that North America was an empty wilderness, barely inhabited.  By the time the English settlers arrived it was indeed empty, but it wasn’t like that before the first Columbus Day.

My perception of the western hemisphere changed forever when I read 1491: New Revelations of the Americas Before Columbus by Charles C. Mann (Knopf, 2005).  Examining scientific, historical and archaeological evidence, Mann describes what the continents were like before European infectious disease unwittingly changed everything in less than 200 years.  For example…

In 1491 the human population in the Americas was greater than that of Europe, the Central Mexican Plateau the most densely populated place on earth.  Unfortunately American Indians had no immunity to European diseases. Once the flame was lit their contact with each other and with escaped pigs from the Spanish expeditions fanned the plagues across the continents over and over again.  In the 150 years between First Contact (the first Columbus Day) and the first English settlers, 95% of the American Indian population died.

This emptied the hemisphere of its keystone species — humans.  Without the agricultural and hunting pressure of 100 million people the forest grew and other species took over.  For instance, Mann explains that passenger pigeons and bison were not numerous when American Indians ruled the continent but their populations exploded in the sudden the absence of humans.  Wow!

Sometimes while hiking I find a trace in the forest of a former homestead — a row of stones that bordered a field, an apple tree engulfed by weeds, a Norway spruce alone in the woods.  Nature took over the site but I can see the past because someone told me what to look for.  The settlers who arrived in the 1600′s found the continental equivalent of old field succession but no one was there to explain it.

Mann’s book gave me a window on the world before Columbus Day.  If you haven’t read 1491 I highly recommend it.

 

(statue of Christopher Columbus by Frank Vittor, erected by the Sons of Columbus in Schenley Park, Pittsburgh, in 1958. Photo from Wikimedia Commons. Click on the image to see the original)

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Oct 07 2013

On Caffeine

Spider webs with and without the spide on caffeine (photo from Wikipedia)

This blog is made possible by caffeine…  administered every morning in a 16 oz mug of coffee at 5:00am.  Boing!  I’m awake!   It works.  And it makes me happy.

Apparently it is not good for everyone.

According to Wikipedia, Swiss pharmacologist Peter Witt began testing different drugs on European garden spiders in 1948 because a zoologist friend of his, H. M. Peters, was annoyed that the spiders always wove their webs between 2:00am and 5:00am.  Dr. Peters wanted to study web building when he was awake, not when the spiders were.

Naturally it made sense to try caffeine.  Perhaps it would keep the spiders awake longer so that they’d “sleep in” and start weaving after dawn.

Not so!  Instead of time-shifting their web construction, caffeine made the spiders build whacky dysfunctional webs.

In 1995 NASA conducted a similar study and took photographs of the spider webs both before and after caffeine (above).

So much for Dr. Peters’ brilliant idea.  He was forced to study his subjects in the dark.  I’m sure he had to be on caffeine to do it.

Happy Monday.

(photos from Wikipedia. Click on the image to see the original)

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Oct 01 2013

Starling Story Problem

European starlings (photo by Bobby Greene)

When I was in grade school I hated Story Problems in math class — those word problems without formulas, just a bunch of facts to solve.

But life is full of stories.  I overcame my disgust, learned how to turn word problems into formulas, and became a math major.  Thus when I wrote about starling flocks last Friday I began to wonder…

How did the starling population increase from 100 birds released in Central Park in 1891 to 200 million (or more) in 2013?

Using information on their breeding habits and survival rate, I did some crude mathematics and came up with an answer.  First, the facts:

  • Starlings north of the 48th parallel produce only one brood per year, the rest produce two.  (To give you an idea of this location, the western U.S.-Canada border is at the 49th parallel.)
  • Female starlings typically lay 5 eggs per nest.
  • 50% – 80% of the eggs survive to the fledgling stage.
  • 20% of the fledglings survive to adulthood.
  • 60% of the adults survive each year.

(Warning!  If math makes your head spin, now’s the time to skip to the end.)

If we started with 100 starlings in Pittsburgh this spring, how many starlings would we have next spring?   To make it simple I made some big assumptions and did a lot of rounding.

  • 100 starlings = 50 nesting pairs
  • 50 pairs * 2 nests per year * 5 eggs per nest = 500 eggs this year
  • 50% to 80% of the eggs will fledge.  I used 65% * 500 eggs = 325 juvenile starlings in August.  I rounded this down to 300.
  • 100 adults + 300 juveniles = 400 starlings in August.   This is why we see so many starlings in the fall — and this doesn’t even include the migrants.
  • 60% of the adults survive to the next spring = 60% * 100 = 60 adults in March
  • 20% of the juvies survive the winter = 20% * 300 = 60 former juveniles in March
  • 60 adults + 60 of last year’s juveniles = 120 starlings in March

If I’m right (but I’m not) our starling population increases 400% in August, then winter trims it to an annual increase of 20% by March.

But 20% is too high.  Sixteen pairs survived from the 100 birds released in Central Park in 1891.  If their increase had been uniform it would resemble compound interest over 120 years (1891 to 2011) of about 14%.

(If you skipped the math, join me here.)

Interestingly, scientists estimated that the starling population boom in the western U.S. in the 1970′s was 16% per year, so I got close.

Fortunately the starling population seems to have stabilized so their annual increase is now — perhaps — zero.

How’s that for a story problem?

 

(photo by Bobby Greene)

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Sep 12 2013

No Food, No Water

Mount Desert Rock (photo by krzdweasel, Creative Commons license)

Twenty miles off the coast of Mount Desert Island is a tiny granite outcrop called Mount Desert Rock.  On a clear day you can see it with binoculars from the mountains of Acadia National Park. It looks like an improbable ship, taller than it is long.

Only 3.5 acres in size, Mount Desert Rock holds three buildings and a lighthouse just 17 feet above sea level. During winter storms and hurricanes the ocean washes over the island and punishes the buildings. The boathouse was swept away during Hurricane Bill in 2009. Isolated and exposed the Rock stands alone. Click here to see how small it is.

Map showing location of Mount Desert Rock (image from Wikimedia Commons)

Whale watching tours from Bar Harbor sometimes circle the Rock.  That’s how I’ve come close but never landed.  The Rock has no harbor so even those authorized to land can only do so when the sea is calm.

Lighthouse keepers and their families used to live year-round on the island, sheltering in the lighthouse during storms.  Since 1998 the College of the Atlantic has had whale and seal study crews posted there on temporary assignment, but they leave before a storm.

No matter who is stationed there, they must survive on food and water shipped from the mainland.  Rainwater is collected in a cistern under the keepers’ house but it’s undrinkable.  Nothing can grow there because the ocean washes away the topsoil in every storm.  And there is noise: The foghorn blares every 30 seconds.

When the weather is right, songbirds take a shortcut across the Gulf of Maine during fall migration from Nova Scotia to Maine.  From the whale watch boat I’ve seen ruby-throated hummingbirds and robins pumping their way past the Rock to Mt. Desert Island 20 miles away.  It’s scary to think they are over open water, sometimes fighting the wind, spending themselves to make landfall on the shores of Acadia — or else they will die.

Fly safe, little birds.  The Rock is no place to rest.  No food.  No water.

(photo by “krzdweasel” via Flickr, Creative Commons license.  Click on the image to see the original. Map from Wikipedia.)

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Aug 27 2013

This Makes It 2,000

Published by under Musings & News

Fireworks (photo by Jon Sullivan via Wikimedia Commons)

Riffing on the number 2,000… yesterday I wrote about a hummingbird drawing 2,000 years old.  Today…  Ta dah!  This is my 2,000th blog post!

Almost six years ago I began blogging every other day.  By now I write daily posts and more when there’s breaking peregrine news.  My husband notes that this sustained effort is roughly equivalent in length to War and Peace.

That’s a heck of a lot of writing, so for today I’m going to take a break and encourage you to do two things using the panel on the left:

1.  Try the search box.  Find something interesting in my other 1,999 entries.  Search for anything — a noun, a verb, an adjective.  Below you can see that I searched for the word “intriguing.”  Scroll down to read older posts you may have missed.

2.  Donate to the blog.  My blog is hosted at WQED Pittsburgh, where I work as Director of Information Technology for both TV and radio.  Like all public broadcasting stations we rely on donations to keep us going.  If you like this blog, make a donation of any size to show your support.  Click on the hummingbird graphic.

Thanks!

p.s. The screenshot below shows you what to do.

Screenshot from Outsdie My Window: How to celebrate the 2000th

 

(photo of fireworks in the public domain from pdphoto.org via Wikimedia Commons. Click on the image to see the original)

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Aug 26 2013

2000-Year-Old Drawing of…

Published by under Musings & News

Retouched photo of Nazca hummingbird (photo from Wikimedia Commons)

Here’s a 2000-year-old drawing of a very cool bird.  Can you tell which one it is?  (For a better view, click on the image to see the larger original.)

While researching hummingbirds I learned about this geoglyph, one of the many Nazca lines found on the dry landscape of southwestern Peru near the towns of Nazca and Palpa.  From the air the land looks like a giant sketchpad with hundreds of geometric figures, humans and animals.  There are even erasures and newer drawings superimposed on top of old ones.

The Nazca people created these lines when their culture thrived here between 200 BC and 600 AD.  The figures were community projects created by removing the top layer of dark reddish pebbles to reveal the light-colored soil beneath.   This desert is one of the driest places on earth and so stable — no wind, rain or vegetation — that the lines have endured to this day. They were protected as a UNESCO World Heritage Site in 1994.

The geoglyphs are as large as 660 feet across, some drawn on hillsides like murals, others in the valley.  The hummingbird is 310 feet long and is a single line that can be walked without crossing itself.  Archaeologists believe these walks were ceremonial, possibly done as a group or community.

I’m impressed that people can create a shape on this scale.  The artist has to spatially translate a small drawing into landscape size.  I can do this for easy things such as “walk in a circle in the living room” but nothing like this!   (In Pittsburgh we’ve done this like flash mobs that spell Google or make the shape of a Pitt Panther.)

Line-making in the Peruvian desert ended after 800 years because of local climate change.  The Nazcas’ only water came from horizontal wells and intermittent rivers fed by rain on the western slopes of the Andes.  When that rain ceased to fall, the wells and rivers went dry and that was that.

See more of the drawings in this six minute slideshow.

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

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Aug 21 2013

Rescued!

Great egret trapped in high-strength fishing line (photo by John Beatty)

When fishermen and trappers abandon their lines in the water, they hurt unintended victims.  One careless individual nearly killed a great egret in York County, Pennsylvania.

Thanks to John Beatty, Ann Pettigrew, TriState Bird Rescue and a whole host of caring volunteers the bird was saved.  Here’s the story in John Beatty’s words:

On August 8th 2013 at William Kain Park I noticed an Egret was trailing behind some high-strength fishing line with a hook attached inside of the corner of its mouth. It was later discovered that this line was left behind by someone attempting to catch Snapping Turtles in the lake. I called the Fish & Game Commission and they dispatched out an officer but before he arrived a couple of local York County Parks employees happened to stop by as well. With a coordinated effort they were able to corral this bird into the woods, capture and retrieve it. By another coincidence there happened to be a veterinarian (Ann Pettigrew) of the Leader Heights Animal Hospital out taking photographs and she offered her help to bring the bird back to her office. The hook was removed from the bird’s throat and after being treated and nursed back to health it was released on August 18th. It was very nice that they invited me to come and take photos at the release of the bird.

Above, the egret struggles to remove the line but the hook is lodged in his throat.  In fact it has gone through and is protruding from his neck.

Below, county park naturalists Fran Velazquez and Kelsey Frey slogged through mud, water and thorns to catch the bird.  Wrapped in a towel, they are holding its beak (through the towel).  You can see its black feet near Kelsey’s gloved left hand.

GREG_rescue_9464685065_c040a60d68_c_rsz_johnbeattyGreat egret captured to rescue it from fishing line (photo by John Beatty)

 

At Leader Heights Animal Hospital, Dr. Ann Pettigrew removed the hook and heavy-duty string and treated the bird. Then she took it to Tri-State Bird Rescue for rehab.  In only ten days it was healthy and ready for release.

On August 18 everyone turned out to see the bird fly free.  Here Teresa Deckard of Bird Refuge of York County opens the box.

Great egret released (photo by John Beatty)

That’s one happy egret!

Thanks to all the good people who made this happy ending possible.

Don’t miss John Beatty’s beautiful photos of this egret’s rescue and release.  Click here or on any of the photos to see the entire story.

(all photos by John Beatty)

 

p.s. In the Comments I have transcribed Ann Pettigrew’s PABIRDS report of this egret’s rescue on August 8.

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Aug 16 2013

No Birds Here

Downtown Pittsburgh from the Ft Pitt Bridge (photo from Wikimedia Commons)

Which place has fewer birds:  a city?  or a cornfield?

When birders visit cities they often think, “There are no birds here.”  This isn’t accurate, but I think so too until I realize there’s a very high quantity of birds but low quality — lots of pigeons, starlings and house sparrows.  It’s the lack of diversity that prompts the comment.

Bird diversity is highest where the habitat provides a wide variety of food, cover and nesting sites.  A 20-year study of abandoned fields on Long Island found that bird diversity increased with the foliage height.  Since there’s not much foliage in cities the birds we find here are those who nest on or in buildings and eat human refuse or handouts — and the birds who prey on them.  (Peregrines!)

Most songbirds eat insects and invertebrates which are hard to come by in the asphalt jungle. Even hummingbirds who sip nectar feed insects to their young.  If you want birds you must have insects.

Places without insects are biological wastelands because they’re also missing everything that depends on insects, all the way up the food chain.  Here’s a picture of a wasteland.  There are no birds here.Cornfield in Penn Yan (photo by Jamie Lantzy via Wikimedia Commons)

I bet you’re thinking, “That’s not possible. There are plants in that cornfield. There have got to be insects and birds there too.”

Nope.  Today in the U.S. we use more pesticides than we did when Rachel Carson warned us about them in Silent Spring.(1)

90% of the corn we grow is genetically engineered to survive the assaults of herbicides, fungicides and insecticides.  This allows cornfields to be sprayed frequently(2) without hurting the corn.   Seed is also pre-treated with insecticide.

There are no insects in cornfields, no birds, and no plants except corn.  I was amazed when I found out about this at Cornstalks Everywhere But Nothing Else, Not even a Bee.

Not even a bee.  Hmmmm…

 

(credits: photo of Pittsburgh from the Fort Pitt Bridge and a cornfield, both from Wikimedia Commons.  Click on the images to see the originals.  Today’s Tenth Page is inspired by page 620 of Ornithology by Frank B. Gill.)

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Aug 06 2013

I Will Sing With You

Nightingale singing in Berlin ()photo by J. Dietrich via Wikimedia Commons

Yesterday while on my way to somewhere else , I discovered a blog called Goldbird Variations that began when the author started playing music for birds.

Years ago Lisa Rest of Chicago took up the piano again and often played with her window open.  One day a mourning dove flew to the windowsill and sang along.  She didn’t understand what it was doing until later, wanting to share her music with an audience, she rediscovered that the birds were listening outside her window and singing as she played.

Soon she began intentionally playing music for birds, recording their duets and writing about her encounters.  Now she’s hooked on birds and blogging.  I know how that is!

Lisa has perfect pitch and can tell that the birds do too.  Listen to a cardinal sing with her in this post that explains why birds are attracted to music.

Which leads to the nightingale above…

Lisa points out she’s not the only one to play music for birds.   In May 1927 the BBC recorded Beatrice Harrison playing Londonderry Air on her cello in her garden in Surrey as a nightingale sang along.  The bird waits for her phrases and blends in at appropriate times.  Amazing!  Click here to download and play the mp3 recording from the Music And Nature radio program.

I have neither perfect pitch nor musical skill but I’ve encountered birds’ interest in music when I whistle while I hike.  I’m particularly fond of Bach and Beethoven and since I don’t sing well I whistle my favorite tunes.

Their favorite of my repertoire seems to be the second movement of Beethoven’s 6th Symphony, Szene am Bach (Scene at the brook) from his Pastoral Symphony.

Of course the birds like that one!

 

(photo of a nightingale singing in Berlin.  Click on the image to see the original on Wikimedia Commons.  This post was inspired by the Goldbird Variations)

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