[va-richmond-general] a neat article from the NY Times

From Kathy Kreutzer, Chesterfield, VA

August 26, 2008
Friend or Foe? Crows Never Forget a Face, It Seems 
By MICHELLE NIJHUIS

Crows and their relatives ? among them ravens, magpies and jays ? are
renowned for their intelligence and for their ability to flourish in
human-dominated landscapes. That ability may have to do with cross-species
social skills. In the Seattle area, where rapid suburban growth has
attracted a thriving crow population, researchers have found that the birds
can recognize individual human faces.

John M. Marzluff, a wildlife biologist at the University of Washington, has
studied crows and ravens for more than 20 years and has long wondered if the
birds could identify individual researchers. Previously trapped birds seemed
more wary of particular scientists, and often were harder to catch. ?I
thought, ?Well, it?s an annoyance, but it?s not really hampering our
work,? ? Dr. Marzluff said. ?But then I thought we should test it directly.?
To test the birds? recognition of faces separately from that of clothing,
gait and other individual human characteristics, Dr. Marzluff and two
students wore rubber masks. He designated a caveman mask as ?dangerous? and,
in a deliberate gesture of civic generosity, a Dick Cheney mask as
?neutral.? Researchers in the dangerous mask then trapped and banded seven
crows on the university?s campus in Seattle. 

In the months that followed, the researchers and volunteers donned the masks
on campus, this time walking prescribed routes and not bothering crows.
The crows had not forgotten. They scolded people in the dangerous mask
significantly more than they did before they were trapped, even when the
mask was disguised with a hat or worn upside down. The neutral mask provoked
little reaction. The effect has not only persisted, but also multiplied over
the past two years. Wearing the dangerous mask on one recent walk through
campus, Dr. Marzluff said, he was scolded by 47 of the 53 crows he
encountered, many more than had experienced or witnessed the initial
trapping. The researchers hypothesize that crows learn to recognize
threatening humans from both parents and others in their flock.

After their experiments on campus, Dr. Marzluff and his students tested the
effect with more realistic masks. Using a half-dozen students as models,
they enlisted a professional mask maker, then wore the new masks while
trapping crows at several sites in and around Seattle. The researchers then
gave a mix of neutral and dangerous masks to volunteer observers who,
unaware of the masks? histories, wore them at the trapping sites and
recorded the crows? responses.

The reaction to one of the dangerous masks was ?quite spectacular,? said one
volunteer, Bill Pochmerski, a retired telephone company manager who lives
near Snohomish, Wash. ?The birds were really raucous, screaming
persistently,? he said, ?and it was clear they weren?t upset about something
in general. They were upset with me.?
Again, crows were significantly more likely to scold observers who wore a
dangerous mask, and when confronted simultaneously by observers in dangerous
and neutral masks, the birds almost unerringly chose to persecute the
dangerous face. In downtown Seattle, where most passersby ignore crows,
angry birds nearly touched their human foes. In rural areas, where crows are
more likely to be viewed as noisy ?flying rats? and shot, the birds
expressed their displeasure from a distance.

Though Dr. Marzluff?s is the first formal study of human face recognition in
wild birds, his preliminary findings confirm the suspicions of many other
researchers who have observed similar abilities in crows, ravens, gulls and
other species. The pioneering animal behaviorist Konrad Lorenz was so
convinced of the perceptive capacities of crows and their relatives that he
wore a devil costume when handling jackdaws. Stacia Backensto, a master?s
student at the University of Alaska Fairbanks who studies ravens in the oil
fields on Alaska?s North Slope, has assembled an elaborate costume ?
including a fake beard and a potbelly made of pillows ? because she believes
her face and body are familiar to previously captured birds.

Kevin J. McGowan, an ornithologist at the Cornell Laboratory of Ornithology
who has trapped and banded crows in upstate New York for 20 years, said he
was regularly followed by birds who have benefited from his handouts of
peanuts ? and harassed by others he has trapped in the past.
Why crows and similar species are so closely attuned to humans is a matter
of debate. Bernd Heinrich, a professor emeritus at the University of Vermont
known for his books on raven behavior, suggested that crows? apparent
ability to distinguish among human faces is a ?byproduct of their acuity,?
an outgrowth of their unusually keen ability to recognize one another, even
after many months of separation.

Dr. McGowan and Dr. Marzluff believe that this ability gives crows and their
brethren an evolutionary edge. ?If you can learn who to avoid and who to
seek out, that?s a lot easier than continually getting hurt,? Dr. Marzluff
said. ?I think it allows these animals to survive with us ? and take
advantage of us ? in a much safer, more effective way.?

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