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Photo of Bernd Heinrich Bernd Heinrich as seen on
Animal Einsteins: Figure That One Out

Click on Bernd's photo to read a brief bio.

q What's the most remarkable thing you've ever seen a raven do? Julia

A The most remarkable thing I've ever seen a raven do is rather than pecking little chips out of a big hunk of suet, as most birds do, this bird "sliced" off a big hunk that he could fly off with; he carved out a groove with dozens of pecks all aligned till he got the big chunk. That's planning, and postponing immediate gratification to achieve greater gratification later.

q I'm curious about how crows have earned their "A-plus" reputation for intelligence and are generally considered the smartest bird. Any insights? Sam R.

A I don't know how crows got the A plus rating, except maybe that subjectively they just seem aware.

q Alan Alda said that different ravens came up with different solutions to your meat on a string test. What were some of the other ways that ravens got the meat? Tegan in Mrs. Greene's science class

A The different solutions of getting meat on string:
  1. Flying at it and just trying to rip it off. Works a little with soft meat.
  2. Some do it by trying to rip the string off, break it, or tear it. No success!
  3. Pulling it straight up.
  4. Pulling it up along the branch, rather than up in loops.

q What are ravens communicating when they caw, and are there different types of caws signifying different messages? Steven

A Ravens have many calls besides caws. Different calls do have different meanings, but we know very little about them. However, most indicate mood, and meaning is then found in context where used. Some calls keep others away, others attract. Calls indicate also the bird's status, sex and intent, aside from mood.

q In the experiment in which you put the meat on the string and had the raven get the meat, could you do that with another bird or does it have to be a raven? John

A I tried the string-pulling test with two crows (not an adequate sample) and both acted clueless. Earlier this century there had been tests with finches and parids (chickadee-like birds) that were negative, unless the birds were trained extensively first. I suspect some parrots could do it, but I know of no published results.

q What other experiments have you designed to test the intelligence of crows? Justin

A I describe numerous observations and tests that relate to ravens' intelligence in a new book coming out in March, titled "Mind of the Raven".

q How long have you been working with ravens, and how did you first decide to study this particular bird? (asked by many viewers)

A I've had pet corrids since I was about 8 years old. I started working with ravens 15 years ago, when I made an observation that greatly puzzled me (I wrote a book about it called "Ravens in Winter").

Bernd Heinrich is also featured in Cool Careers in Science. Check it out!


Scientific American Frontiers
Fall 1990 to Spring 2000
Sponsored by GTE Corporation,
now a part of Verizon Communications Inc.