April has you on a grand tour of North America visiting a different grouse lek each day. The only downside is that all the early mornings and long drives (and perhaps a bit too much celebration last night for your latest lifer) has you feeling a bit discombobulated this morning. In fact, all you can remember is that you drove to some lek where you spent the night. Now these two birds are walking around, but what are they? Range is a great way to identify grouse, but you have no idea where you are. Now what?
Luckily it’s not difficult to figure out that you are looking at some kind of grouse. Even a superficial glance reveals extensive barring on the underparts, which only fits the two Prairie-Chickens. The only other member of the genus Tympanuchus (Sharp-tailed Grouse) has underparts that are scaled and spotted not barred. Ptarmigan have a much more mottled appearance to the underparts with irregular bars unlike our birds. They also have white wings and lack the elongated neck feathers (pinnae) visible on these two birds.
Note here that the barring on the underparts is extensive, relatively uniform and widely spaced-just as we would expect in Greater Prairie Chicken. While these birds are on the pale end of Greater Prairie-Chickens, they are not at all unusual. While pale, this appearance affects the upperparts and all the underparts evenly (meaning that the upperparts and upperparts are equally pale compared to a “classic” Greater Prairie-Chicken). By contrast, Lesser Prairie-Chickens have paler barring that is most noticeable on the central belly. The upperparts of Lesser Prairie-Chicken also much more finely barred with the narrow black barring on the upperparts-quite different from the broad bars visible on the upperparts of this bird.
If you’re still not quite convinced, that’s okay. Take out your GPS and see that it’s early April, and you are in northeastern Colorado at a Greater Prairie-Chicken lek north of Wray, Colorado. (The range of Lesser and Greater Prairie-Chickens comes very close in central Kansas and Oklahoma, but does not overlap.)
The photo and answer were supplied by Chris Wood.