Eurasian Sparrowhawk
Adak, Alaska, September 21, 2016
 

When we first encountered this bird, I got it in my scope and said to myself “It is a small accipiter.”

I grabbed the camera and took 6 distant photos (the two best below). As soon as we inched the truck closer, the bird flew away, quickly disappearing over the hilltop. I got no other photos.

Total observation time – less than a minute.

We searched the rest of the day, and Thursday morning, to no avail.

As we were looking for the bird, I reviewed the photos in the camera and saw what looked like a Goshawk. We grabbed the field guide we had on hand (Birds of East Asia - Mark Brazil) and turned to the accipiter pages. Nothing on the first page matched what we saw. The second page had Eurasian Sparrowhawk and Northern Goshawk. Unfortunately, the illustration of the female sparrowhawk does not do it justice and the head pattern is very muted.

So I allowed one half of my brain (the plumage-driven Goshawk side) to overrule the other side (the small accipiter side) and assumed my size-perception was off and went with Goshawk. Even so, I was bothered by the white markings on the back. I have seen thousands of Sharp-shinned and Cooper’s hawks and hundreds of Northern Goshawks in my birding career (I was a hawkwatcher and counter at Hawk Mountain in my early birding days), and have see many Sharpies and Coops with those kinds of markings on the back, but never a Goshawk. They may occur on Goshawks, but I just never ran into them. That led to my IDFrontiers post asking which subspecies this was and what the back-markings meant.

That was Wednesday night.

Thursday morning, I was greeted with several suggestions from IDFrontiers contributors to reconsider Eurasian Sparrowhawk. I looked again at the field guide and then went online to look for photos. The third image I found matched our bird exactly! I now realized I should have stuck with my initial size estimate! So I changed the ID to sparrowhawk.

Subsequent posts by IDFrontiers contributors have solidified that decision.

Responding to an excellent suggestion from John Puschock (who had a Eurasian Sparrowhawk on Adak a few years ago – but didn’t get identifiable photos), on Thursday morning, I climbed up the hill where we had seen the bird and took photos of the branch it was sitting on with a 12-inch ruler attached to provide scale (What the bird was doing with a 12-inch ruler, I will never know...).

Those photos are on the link above and confirm the size of the bird.

We had been traveling home since Thursday afternoon, arriving last night, so that is why we have been quiet on this post until now.

So there you have it. A first confirmed North American record.

 

 

Original photo size

 

 

Cropped photo


 

Cropped photo


 

Size determinaton

On Thursday, September 22, I climbed up the hill and tied a 12-inch ruler to the trunk and then the branch of the tree where the bird had been photographed.

The following photos are scaled to the same size. The white rectangle on each photo is the same size for each and is 12 inches high and the width is the distance from the trunk to the bend in the branch.

On the bird photo, the rectangle is positioned at the top of the head and it can be seen that the bottom of the smaller rectangle (12 inches) crosses the middle part of the tail. The larger box goes to the tip of the tail (At least I think that is the tip of the tail. If it isn't, then the bird is even smaller!).

This makes this bird right in line with the size of a Eurasian Sparrowhawk.


Original Adobe Illustrator version of the above page (25Mb).