Monthly Archives: February 2011

Scratching

Bird Anatomy, Bird Behavior

11 February 2011

Itchy?  Actually, she’s probably preening.

Preening is very important to a bird’s health and well-being.  If her feathers aren’t in top condition she’ll lose warmth and perhaps some flight ability.

Birds spend hours every day methodically preening their feathers, using their bills to spread oil from their preen glands, align the feathers and remove parasites.

Many tiny parasites have evolved to eat feathers.  Chewing lice eat the down and barbules, leaving the vane and barb structure.  This gives damaged feathers a thin, almost see-through appearance.

Since their bills can’t reach their head and neck feathers, birds use their feet to vigorously scratch away the parasites.  This works so well that the reverse it true.  Those who are crippled or have lost a foot carry a heavy parasite load.

If you look closely at this female goldfinch you’ll see that the feathers on her scratching side look thick and normal but those on her non-scratching side look thin.  I wonder if this is feather damage.  Poor dear.

Scratching is good.

(photo by Chuck Tague)

Famous?

Mammals


Last week groundhogs had their day.  This week possums are vying for the spotlight.

Possums have come up five times in the last seven days and the more I’ve looked into them, the more intrigued I’ve become.  Did you know that….?

  • Virginia opossums (Didelphis virginiana) are North America’s only marsupial.
  • Their ancestors were from South America but they split from them during the Cretaceous (age of the dinosaurs) and started moving north.  They are still moving north and have now reached southern Canada.
  • Possums are the size of a large housecat with a pointed snout, shaggy fur and a naked prehensile (grasping) tail.  This one looks so cute because his ugliest features are not accentuated in his portrait.  It helps that he didn’t smile for the camera.
  • Possums have 50 teeth in their little mouths and look especially grisly when they smile.  (Adult humans have 32 teeth.)
  • They often smile when they’re afraid and always smile when they “play possum” in which they pretend to be dead by rolling over, drolling with an ugly smile, tongue hanging out, eyes closed and a slowed heartbeat.  They can be catatonic like this for four to six hours!
  • Playing possum — looking dead when threatened — is not under their control.  It’s involuntary, like fainting.
  • Possums will eat just about anything and become ill if they don’t have an extremely diverse diet.
  • They are prolific.  The female’s pouch has 13 nipples for up to 13 live young.  This makes up for their survival disadvantages which are…
  • Possums have very low intelligence, poor eyesight (nearsighted), poor hearing and a slow bumbling gait.  Any possum who decides to eat roadkill easily becomes roadkill himself.
  • Possums are normally nocturnal but in times of short food supply you may see them foraging during the day.  That’s when Cris Hamilton found this one on her deck eating fallen bird seed.
  • Their thin ears and naked tail are especially prone to frostbite.  Joan Silagy saw a frostbitten possum at Blue Marsh last week.
  • Possums can live well in the city.  Last Saturday night I saw a one on my city street just after hearing how possums invaded someone’s home (inside the walls!) in New Orleans after Hurricane Katrina.  That double-whammy started my possum streak.
  • Virginia opossums live only about two years in the wild because they face so many predators and the challenge of winter.  The ARL Wildlife Rehabilitation Center has a possum missing an ear and half its tail because a dog attacked it.  (See his thank-you card here which you receive after sponsoring him here.)
  • The possum’s enemies expanded his range.  Southerners who liked possum stew took them to California for food during the Great Depression.

I could go on and on about possums but I’ll leave you with this Possum Celebrity Moment:  A cross-eyed possum at the Leipzig Zoo has so captured the hearts of the German public that the zoo has had to improve her display so that more people can see her — and she’s not even on display yet!

(photo by Cris Hamilton)

Swamp Thistle in Winter

Winter Weeds & Trees


Swamp Thistle is showy when it blooms and has large, dried flower heads when it dies. 

A native biennial in the Cirsium genus, swamp thistle stands five to ten feet tall and produces 1″ long purple flowers on hollow, spineless stems.  When the plant flowers in mid to late summer it’s in its second year, so by the time you find its dried flower heads in winter the plant is dead.

Look for swamp thistle in swamps, wet woods and thickets.  On the ground nearby you’ll see its first year plants overwintering as flat rosettes of prickly leaves.

My Weeds in Winter book says you can easily find these rosettes if you walk barefoot in the vicinity of the flowering plant.

Yow!  Not a good idea!

(photo by Dianne Machesney)

Moving Day

Birds of Prey, Nesting & Courtship

Sometimes a bird picks a dangerous place to nest.

In Tampa Bay, Florida a male osprey began building a nest to attract a mate but he chose a railroad signal tower as his ideal location.  It looked good to him, but it was a big problem for the railroad.

Fortunately volunteers from the Audubon Society of Clearwater Florida had a better idea.  Watch the video to see how they worked with CSX to move the osprey’s nest.

Would the osprey accept the new location?  You bet!   Moving Day was a success.  Here he is perched at his new home.

Now all he has to do is unpack the sticks.  😉

Thanks to Bob O’Malley for sending me this happy news.

(video and photo by Bob O’Malley)

Quiz: What plant is this?

Quiz


I can usually identify this plant in a heartbeat, but I was stumped when I saw this photograph.  Maybe you will be too, so I’ve made it a quiz. 

Here are some clues:

  • The plant is a perennial native of Asia.
  • It’s invasive in North America wherever it’s found.
  • The stems are hollow and stand over 10 feet tall, persisting through the winter.
  • The plant spreads by wind-borne seeds and rhizomes. 
  • The rhizomes are particularly difficult to eradicate and result in dense stands of this plant.
  • It was originally brought here as an ornamental because it’s flowers are arranged in pretty cream-colored sprays above the stems.  (This is the flower stalk in winter.)
  • The young stems are edible and taste like rhubarb but Americans don’t like it well enough it to reduce its population by harvesting.

Do you know what it is?  Leave a comment with your answer.

(photo by Dianne Machesney)

Beyond Bounds: White-tailed Kite

Beyond Bounds, Birds of Prey


I have been mesmerized by this photo since the moment I first saw it.

I’m drawn in by the bird’s ghostly white color, by the warning look on its face, by its intense, red eye.

This is a white-tailed kite, a hawk that hunts rodents in open scrubland by hovering kite-like in the air.  As scary as this bird looks to us, it rarely eats birds so most flocks ignore it. 

The majority of white-tailed kites live in Central and South America but their range extends into western California, western Oregon, southeastern Texas and southern Florida.  They are not plentiful in North America but they can travel widely. 

Cris Hamilton photographed this one at Bosque del Apache, New Mexico last November.

(photo by Cris Hamilton)

Invasive Thaw

Insects

Freeze. Thaw. Freeze. Thaw.  Pittsburgh’s weather has been a yo-yo while we hear with horror of blizzards and nor’easters 400 miles away.

While Chicago shut down we had rain.  Lots of it.

We also had a resurgence of brown marmorated stink bugs.

It was so warm on Wednesday that they emerged from their secret hiding places to see if spring had come.  That night the temperature fell to 20o and they were driven indoors, moving in slow motion, all their energy spent in that brief moment of false spring.

Coincidentally I received an email from a fellow Pittsburgher, Jim Valimont, who’s travelling out west right now. 

He said, “One of the things that I’ve noticed since we’ve been in Arizona and California is that stink bugs are waking up and coming out of our van.  I’ve seen seven, killed six, but one got away.  Think of all of the other snowbirds releasing stink bugs in the south and west this winter.  They’re going to be everywhere in a few years.”

So now we know there’s more than one way to thaw a stink bug.

Watch out, California!

(photo of a brown marmorated stink bug from Wikimedia Commons.  Click on the photo to see the original — an enormous close-up — if you dare.  It’s probably more than you want to see.)

Anatomy: He Has a Beard

Bird Anatomy, Doves & Chickens


Even though this turkey’s chin is scruffy, that’s not where his beard is. 

The “beard” on a wild turkey is that cluster of long hairlike feathers sticking out of the center of his chest.  They average nine inches long. 

Generally only male turkeys have beards but 10 to 20 percent of female turkeys grow them as well.  This poses a problem for those ladies during Spring Gobbler hunting season when only bearded (i.e. male) turkeys can be hunted. 

Don’t worry about this turkey, though.  He’s probably safe all year long because he’s a regular in Cris Hamilton’s back yard.

(photo by Cris Hamilton)

Another sighting

Peregrines


How about that!  Just this morning I mentioned that peregrines will be courting in February and they proved me right. 

Here’s E2 visiting the nest box at the University of Pittsburgh at 11:39am.  He’s looking up to see if Dorothy will come down to bow with him.  (She didn’t.)

(photo from the National Aviary snapshot camera at University of Pittsburgh)

Peregrine Sightings

Peregrines

In the gloomiest days of winter I remind myself that I will like February.

It’s a great month to be a peregrine fan.

This is when peregrine falcons in the mid-latitudes (Pennsylvania, Ohio, etc.) begin their breeding cycle.  They claim their territory and advertise for mates.  If they already have a mate, they court and renew their pair bond.  The male brings food for his lady, they fly together and bow at the nest. 

All of this activity is big and brash.  They want everyone — especially other peregrines — to know they’re there.

In late January peregrine sightings increased.  Here’s news from around the area:

  • At the University of Pittsburgh, Karen Lang and I have seen E2 and Dorothy perching near each other and E2 bringing breakfast to Dorothy.
  • At the Gulf Tower downtown, Barb Becker, Sean Brady and Sharon Leadbitter have all seen Louie and Dori warming up to the breeding season.  Louie is very vocal.  He’s hard to miss when he has something to say!
  • On January 28 in Rochester, PA, Mark Vass saw a pair of peregrines attack a bald eagle and force him down to the ice of the Ohio River.  This was probably the Monaca Bridge pair defending their territory. 
  • Several birders have seen a peregrine near Brunot’s Island probably one of the pair who nests at the McKees Rocks Bridge.  That bridge is huge and these birds are hard to find.
  • On Tuesday, Steve Gosser took this photo of a peregrine at the Tarentum Bridge. 
  • And here’s an intriguing sighting by Shannon Thompson on January 9, seen from Presque Isle State Park in Erie, PA:  “Peregrine Falcon, 2 together on stacks near East Bay Boat Ramp.”   Wow!!  A pair perched together is definitely courting.  I haven’t heard that peregrines nest in Erie.  Is anyone monitoring this pair? 

As you can see, it’s going to be a great month to be a peregrine fan. 

Keep looking up.

(photo by Steve Gosser)