You know how embarrassing it is to
introduce yourself to someone at a party, and realize too late that you’ve
already met? Just imagine if that person was a bear.
To prevent moments like this, San
Diego Zoo conservation researcher Russell Van Horn and his
colleagues asked people to try identifying bears by their faces.
Actually, their motivation had nothing to do with awkward party moments. It had
more to do with citizen science. Can volunteers be trusted to look at photos
from a camera trap, say, and report how many different animals have walked
past? What about scientists? If someone thinks she’s seen
ten different animals when she’s only seen five, the population
count for an area could end up artificially high. What looks like a
healthy population could really be a lonely few animals who are hard to
recognize in different lighting.
The researchers gathered photos of
Andean bears (Tremarctos ornatus, also called spectacled bears) from
zoos and research sites around the world. Individuals of this species have
markings on their faces that make this task a little easier than it might
be otherwise. The pictures showed bears of known identity and age at different
times. Sometimes the pictures were at bad angles or hard to make out, as they
would be in research.
In an online test, 120 participants
viewed pairs of photos and answered one question: Is this the same animal?
People were only OK at this. They answered
correctly more than half the time, whether the pictures showed a cub
and an adult or two adult bears. But when cubs’ markings changed with age
(sometimes facial markings fade, and elderly bears often
“grizzle” like dogs), people did even worse than if they’d been
guessing. It didn’t help if participants had worked with bears or animal
identification before—which many of them had, since the researchers recruited
some people they knew. A second experiment showed that a training session
didn’t dramatically improve people’s results.
But it wasn’t all dire news. A
handful of subjects (five of them in the online test) got every bear
identification right. And while training didn’t help much, motivated
people who viewed a lot of bear photos did improve.
This shows that local citizen
scientists can help out with bear identification studies, Van Horn writes. They
just need some practice first. And no one—citizens or researchers—should rely
on a single person’s identification of a bear.
Ready to try?
The bears numbered 1 through 6 below
are younger bears from the study, some cubs and some adults. The
pictures marked A through F are the same bears later in life. Match
each number with a letter.
Cubs and younger bears
Adults and older bears
Answers are below.
Did you ace the quiz?
Congratulations—you’ll be more than prepared for your next cocktail party! If
you talk to people you haven’t seen in a while, be sure to comment on
their grizzling.
Images: from Van Horn et al.
Horn,
R., Zug, B., LaCombe, C., Velez-Liendo, X., & Paisley, S. (2014). Human
visual identification of individual Andean bears. Wildlife Biology, 20
(5), 291-299 DOI: 10.2981/wlb.00023
Answers: 1B, 2D, 3C, 4A, 5F, 6E.
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