The Cornell Lab Bird Academy › Discussion Groups › Anything but Common: The Hidden Life of the American Crow › Crow Research Techniques
-
in the hand
-
That they take the babies so young to mark and study. Also that the markings stay on for such a long time. That crows live to be 19 years old
-
Getting up to those tall nests! AND blue-eyed young. I learned that in ornithology, but had forgotten.
-
I knew most of it as I have been corvid crazy since the cradle and have followed Dr. MacGowan's work for a very long time. I guess the fact that the team could so closely follow individuals and identify their relationship with other other birds within the different flocks/families.
-
That they can climb up into those high trees to tag babies in the nests and that it doesn't disturb the mother's interest in her nest. Also the multiple banding method and that sexing the crows comes by taking blood.
-
I didn't know that sex was determined by taking blood and DNA testing. If crows live up to 19 years in the wild, how long would they live if they are in captivity/in a park/non-releasable facility?
-
The way they identify them with three different ids.
-
The multiple banding method and the ability to track crows for 18 years. I did not know they lived this long. This is the kind of meticulous work that reminds me of Jane Goodall tracking primates. Fascinating to know there are such personalities in crows. Admirable work. Great to finally understand why they hang out in cemeteries.
-
I really appreciated that little bit about cemeteries, too!
-
-
1)length of life 2) no down on babies 3) at least in NY, maintain same nests
-
1) that mom and babies tolerate banding, blood samples so well.
-
The longevity of a crow is mind blowing!
-
`my reaction is a repeat of most all comments below. I love that they become individually known over time. I tend to be amazed that they tolerate all that "stuff" on them - bands, and tags, and radio thingies, and that those things do not alter their behavior in some way. Wee comment, if photographers are willing to give up their credits occasionally, it was hard for me not to peek at the credit ... which was often a dead giveaway as to which the crow was). HOWEVER, I still paid attention to the difference and learned something so it was fascinating - though I would count myself fortunate indeed to see a (non-stranded) baby in the field!
-
I'd agree with Ben. I'm amazed at the nest to grave study !! And on a highly individualized level ! Bird by bird, year after year. I'm also amazed to learn of their longevity. I'd have thought crows lived somewhere around five to six years. Eighteen or nineteen !!! Wow !!
-
I thought that crows would have lived way longer than 13 years.
-
I was surprised by their longevity.
-
most interesting was the nest to grave approach. the amount of data that studying individuals that way must generate is kind of mind blowing! also, kudos to you brave souls for scaling such heights to collect data.
-
I liked that they studied the birds as individuals and tracked how they were related to other crows.
-
I was surprised not only by the fact that they took babies but by the blood sampling.
-
I was surprised that researchers took baby crows from their nests.
-
Me too! And that it didn’t disrupt their family life when they put them back again!
-
-
I like how the team can track individuals and find out how long they live and who they hang out with. To get to know the crows as individuals would be so rewarding, like having an old friend. It is so miraculous to see how the little ones look so helpless and how they change over time. It was so interesting how they are born with blue eyes! Neat to see the bird's eye view from their nests. It makes me wonder how you would tell a squirrel nest from a crow nest.
-
I found the details about tagging and how long some of them live very interesting.
-
I learned so many interesting things but most surprising was how long they lived. Also interesting was the blood sample to tell sex of the crow.
-
That the nestlings are tagged three different ways. I have not heard of tagging the wings before. It was neat to learn that the birds can be followed for much of their lives, up to 18/19 years. I was really happy to learn that they are studied as individuals.
-
Putting tags on wings is not uncommon, especially for bigger birds. Wing tags have been used to identify California Condors in the wild for years, especially for those who were captive-bred and then released into the wild. It is much easier to see a large wing tag than any leg bands on a bird that spends much of its time soaring/flying.
-
-
By tagging the birds you were able to find out how their community is structured and how it changes over time.
-
So interesting how you have these study methods . . Two questions: I imagine you have to use the gear that tree trimmers do to get to the tallest part of the tallest tree where the nest and babies are, and handle the babies and put tags and bands that are strange to them. Why does that not spook the parents and make them leave the nest? You always hear that birds and animals will abandon young ones if you scare them or make too much of a ruckus near their nests. If humans need to use a blood test to tell the gender of the birds, how do the birds know who is male and female? I have often wondered this because I have parakeets at home, one type (budgie) I have a male and female you can sort of tell by the color of their nose but the other (parrotlet) you are supposed to give them a dna test to tell. Two of them squabble and the other one so I assume it's the boys arguing over the girl.
-
Erin asked: <
I imagine you have to use the gear that tree trimmers do to get to the tallest part of the tallest tree where the nest and babies are, and handle the babies and put tags and bands that are strange to them. Why does that not spook the parents and make them leave the nest? You always hear that birds and animals will abandon young ones if you scare them or make too much of a ruckus near their nests.>>
Erin asked < < If humans need to use a blood test to tell the gender of the birds, how do the birds know who is male and female? >>
There are some differences between male and female that a crow would be better able to access than a human or researcher. We are not aware of any studies that have been done to determine how the crows themselves know male vs. female. The male does have a slightly lower voice than the female and while that is difficult for humans to easily use for "sexing" a bird the crows themselves might be better at using voice to tell male from female. There are probably other differences they pick up on such as slight differences in bill size or shape. Even trained researchers have a difficult time with any visual differences and that is why to be 100% sure researchers go by DNA tests. There are probably behavioral cues they could pick up on but without a proper study it is all speculation. Thanks for asking.
-
Read More: