A research trip on Northern Goshawks

I’d like to introduce you to the Northern Goshawk (Accipter gentilis).  This predatory bird rules the forest.  They are battleship gray with eyes that reflect the blood color of squirrel and bird meat that they eat and feed their nestlings.  Goshawks are as fearless as they are fierce.  If you get anywhere near the nest they will come at you with talons open, and you have to dodge and duck or risk getting your face raked open.  To learn more about Goshawk research in Idaho, visit the blog of Rob Miller.

Northern Goshawk, Intermountain Bird Observatory
Meet the Northern Goshawk, absolute ruler of the forest. Photo © Robert Miller.

As a biologist and tree climber, I am asked on occasion by other biologists to aid in their research.  Such is the case here, where I helped Intermountain Bird Observatory and Boise State University with research on one of the coolest raptors in North America.  It’s no lie that I admire this bird.  I weigh about 65 times more than one of these birds, but it takes a lot of nerve to climb into one of their nests because they are literally trying to rip my head off, and they have the means.  But I digress.  The few photos below tell the story of a climb into a single nest in June of 2015.

On the ground looking up a lodgepole pine (Pinus contorta) that makes up this stand.
On the ground looking up a lodgepole pine (Pinus contorta) that holds a Goshawk nest near the top.

Goshawks like to nest in mature forests with trees of different ages and sizes.  On the Sawtooth National forest that means quaking aspen and lodgepole pine.  The above tree was about two feet in diameter, and the nest was about 40 feet high.

Halfway up the tree, the view looks like this.
Halfway up the tree, the view looks like this.

Lodgepole pines aren’t usually very big, and it only takes a few, maybe 30 minutes, to get up the tree.

Getting close to the nest, and this is the first good view.  The trick is to climb high enough past the sticks and branches to be able to reach into the nest.
Getting close to the nest, and this is the first good view. The trick is to climb high enough past the sticks and branches to be able to reach into the nest.
Reaching for a Goshawk chick in the nest.  They don't like it much!  There are two more in the background, standing as far away from me as they can get.
Reaching for a Goshawk chick in the nest. They don’t like it much! There are two more in the background, standing as far away from me as they can get.

Once at the nest, the trick is trying to get my hands on a feisty bundle of feathers that wants nothing to do with the clumsy white monkey with a helmet.  They have talons and sharp beaks but don’t really know how to use them yet.  Still, it’s important to be cautious and not hurt the little guys.

There is a Goshawk chick in my right hand, and you can see the banding crew in the background.  In a few more seconds I'll lower it to the ground in a soft cotton sack attached to the climbing rope.
There is a Goshawk chick in my right hand, and you can see the banding crew in the background. In a few more seconds I’ll lower it to the ground in a soft cotton sack attached to the climbing rope.

The next task is to get squirming and angry birds to the ground.  I slide them into an elastic sleeve, slip them into a soft cotton bag, and lower them to the ground where a team of biologists is prepared to attach leg bands and take blood samples.

I'm about to return this Goshawk chick to its nest.  All that remains is to slide it out of the sleeve and lay it in the nest.
I’m about to return this Goshawk chick to its nest. All that remains is to slide it out of the sleeve and lay it in the nest.

I lower the chicks one by one, and after they are “processed” (fancy biologist word for getting banded and any needed samples taken, weighed, etc.) I raise them on the rope one by one.  Above, one chick is in the nest, and I’m about to slide another out of its sleeve and back into its home.

Northern Goshawk chick displays its new color band.  Apparently it likes the color purple.
Northern Goshawk chick displays its new color band. Apparently it likes the color purple.

This chick has realized that we mean no harm and are dishing out free jewelry, so it has calmed down a lot.  OK, just kidding.  But you can see some features of the nest in this photo: loose sticks, and lots of greenery that adults use to “decorate” (another biologist term, as if raptors really decorate their homes) the nest.  It is speculated that the fresh pine branches help repel flies that are attracted to rotting squirrels and woodpeckers in the nest.  Hint: doesn’t work!

Rappelling from the tree on a figure-8 is quick and easy.
Rappelling from the tree on a figure-8 is quick and easy.

Biologists don’t take this kind of work lightly.  We know that our intrusion has an impact on the birds.  Our goal is to be in and out of the nest in less than an hour.  Having good climbing skills and being a trained ornithologist help to reduce the time.  But honestly?  It’s a lot of fun.

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All photos © David L. Anderson, except the fine Goshawk photo at the lead, compliments of Rob Miller.

4 thoughts on “A research trip on Northern Goshawks”

    1. Rob, one of the best things is when we all share talents and adventures. I love the feeling of taking science and conservation forward, and working with other professionals. I always feel better for it.

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