Monthly Archives: July 2011

This is Not a Honeybee


But it sure looks like one.

On Wednesday I blogged about Sundrops and included a photo of a flower with a honeybee on it — or so I thought.  Fortunately Monica Miller pointed out my mistake (which I corrected) and I learned something new.

This bug is a honeybee mimic who looks so similar he’s often mistaken for one.  He’s the same size as a honeybee and has a dark brown body with orange-yellow patches covered in short hairs.  He hovers like a bee and he feeds on nectar. 

But he’s a drone fly, a member of the family Syrphidae also known as hover flies.  This one is in the genus Eristalis and is probably the most common species, Eristalis tenax, but drone flies are so hard to tell apart that it’s beyond the capabilities of someone like me who only just learned they aren’t bees!

How do you tell the difference between a drone fly and a honeybee?  The drone fly is a “true fly” so he has:

  • only one pair of wings
  • large eyes (which happen to have a row of upright hairs on them)
  • no waistline (honeybees have a narrow waist)
  • inconspicuous antennae
  • and no sting!

In the larval stage you’ll never mistaken a drone fly for a honeybee.  Drone fly larvae live in stagnant water and feed on decaying organic material.  The water they prefer is so low in oxygen that they have tubes on their rear ends that they raise to the surface to breathe.  This gives them the nickname rat-tailed maggots.  Eeeeeew!  They like manure pits. 

Drone fly adults are good pollinators so perhaps that’s why they were introduced into North America around 1875. 

I don’t know how they got here, but I do know I prefer to meet them as adults.

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

Not To Worry

Last week the Pittsburgh Tribune-Review reported that Phipps Conservatory is working through the approval process to install a modern 40-foot vertical-axis wind turbine at their upcoming Center for Sustainable Landscapes.

Since then Tony Bledsoe and I have received inquiries from folks who are worried that this windmill will hurt local birds, especially the peregrines, so I thought I’d discuss it today.  Please keep in mind that these are truly comments, not a news story.  I don’t know anything more than the media reported last week but I do know something about Schenley Park, birds, windmills, and our peregrines.

I’ll address the issues point by point:

  • Approval process:  Phipps is going through an approval process not because the windmill is dangerous but because Phipps Conservatory and Schenley Park are historic landmarks.  The wind turbine needs zoning approval because it’s 40 feet tall (four stories) in a historic setting.
  • It “looks more like a revolving door than a windmill”:   Though I don’t know what model is planned for Phipps, chances are it will look similar to the one pictured here in Rogiet, Wales.  It’s a spinning cylinder less than 10 feet wide.  Click here to see what this model looks like when the wind blows.
  • Will this windmill be a danger to birds?  Not likely.  The danger to birds depends on the location where the windmills are installed, the models used, and the number of windmills at the wind farm.  Altamont Pass Wind Farm, home of the famous killing-windmills, is one of the earliest, largest U.S. wind farms.  It houses nearly 5,000 small windmills on fretwork towers in ground-squirrel (prey) habitat in a migration corridor.  (See what it looks like here.)  The location attracts raptors who perch on the struts to hunt ground squirrels and die when they fly off the towers to capture prey.  Altamont has taught the wind energy industry what not to do.  To drive home that message Audubon won a lawsuit against Altamont’s owners, forcing them to replace the deadliest windmills.  Just to emphasize:  There’s a world of difference between a single 10-ft-wide revolving-door wind turbine in a city setting and 5,000 spinning-blade windmills in California’s migratory raptor habitat.
  • Will it hurt our peregrines?  Nope.  I’m not worried by it at all.  Peregrines are masters at avoiding moving things including waving flags and Life Flight helicopters (which you hear frequently on the Cathedral falconcam).  It’s what they don’t see that kills them.  Windows, not windmills, are the biggest killer of birds.  Birds see the sky’s reflections on windows, not the windows as walls, so they try to fly through them.  Up to 2.7 million birds per day are killed by windows in the U.S.   In 2008 one of Pitt’s young peregrines died by smashing into a window.   If you want to save birds, make windows safe.  Click here to read more from New York City Audubon.

Meanwhile, if you want to see a vertical-axis wind turbine I hear there’s one at the Eat’N’Park at Waterworks Mall near Fox Chapel.  Sounds like a good idea for a field trip:  sightseeing, shopping and eating.

(photo of a vertical axis wind turbine at Rogiet primary school in Wales by Andy Dingley.  Click on the photo to see the original on Wikimedia Commons.)