Monday, January 6, 2014

SIDEBAR #1 - Removal of northern goshawk from the year's list

While the primary purpose of this blog is to keep people abreast of my activities and bird sightings, I also hope to take the occasional chance to discuss issues that are particularly relevant to the birding community at large. Today I will discuss my rationale for removing the northern goshawk from the year's list. I do this to demonstrate how we can use constructive conversations about bird identification to make us all better birders.

To be brief, I based my identification of the accipiter on its very large size and a relatively bold white eyeline. Goshawk is much larger than Cooper's hawk, but because of sexual dimorphism within each species, the difference might not be obvious in all situations. For those that do not know, female birds of prey are always larger than the males of the same species. A female goshawk is characteristically large, but immature male goshawks can be sometimes be confused with larger female Cooper's hawks. The prominence of the eyeline is also variable. Generally, the goshawk's eyeliner is bolder, but again, there is overlap between the species. In short, I based my ID on two characteristics that are variable. The most diagnostic feature is the undertail: goshawk has streaks, Cooper's does not. As the bird I observed perched facing away from me, I was unable to see the undertail.

So, why have I retracted my ID on this bird? A good friend and very well-seasoned local birder sent me a note in which he inquired about the undertail field mark. I told him I did not see it. He then presented a very well-organized synopsis, complete with photos, that made me realize that my ID might have been incorrect. As soon as I realized this, I decided to retract my ID.

I do not think this particular friend was implying that I had identified the bird incorrectly or that I was not a capable birder. I think he merely wanted to bring to my attention the difficulties in basing accipiter IDs on the particular field marks that I used. He presented the information, and I came to the conclusion that I might not be correct. At no point did he take a demeaning tone. The lesson that comes out of this is that if you want to help people become better birders, try to do it judiciously. Try to educate rather than belittle, and realize that everyone (even you!) is wrong at some point.

As Biking for Birds is hugely motivated by the bird list, I want to make sure, both for myself and those following me, that I am keeping a credible one. Removing goshawk will help me rest assured that I trying my best to do just this.


  1. Loving this blog, and will be eagerly following it throughout the year! Small note: your bird #2 is missing from your list of birds. (I think it was that second owl...)

    Best of luck!

  2. Good move and well said. You'll find another goshawk, I'm sure.

  3. Most important is being comfortable with your own decision, so kudos! Plus, now you have another bird to "get".

  4. Excellent post. Uncertainty (or out and out errors) are part of birding (and life, go figure), and those things are great learning experiences. I once publicly mis-ID'ed a bird on a listserv... I did not know that the Louisiana Waterthrush migrates earlier than the Northern Waterthrush - but I'm unlikely to ever forget it now. :)

    And Northern Goshawk? You are On Notice!


  5. Another thing to note about Northern Goshawk vs. Cooper's Hawk ID is the barring on the retrices. Cooper's Hawks always have even barring on the tail. Northern Goshawks always have uneven barring on the tail. Obviously this is probably difficult to recall from your sighting, but if you have a picture you can check this. And I agree with your friend's analysis. The ventral streaking on the contour feathers is much more extensive with a buffy background on the Northern Goshawk.