Saturday, July 04, 2009
Awash in Ammodramus
I think a major highlight of my birding summer so far has been the chance to study all 5 of the Ammodramus Sparrows that occur in the interior US (you have to go coastal to see Saltmarsh Sharp-tailed Sparrow and Seaside Sparrow, a geographic feature my travels in Wisconsin, Minnesota, and North Dakota lacked.) For an overview of this genus, I'll also plug a great new resource- David Sibley has put is seminal field guide online! Link to his section on Emberizine Sparrows and Allies and scroll down to see an overview of the 7 North American Ammodramus (I'll also link to each one.) If I were to summarize this genus, I'd say "small, secretive, shrill (voiced), and subtle" (field marks.) Two were new to me, and I was excited not only to see them but to photograph them all (however poorly in a couple of cases.) The first lifer I got was Henslow's Sparrow. I wasn't expecting this one, being north of their regular range, but one was a bit north of normal at Crex Meadows, a fantastic state wildlife area in Burnett County, Wisconsin. Andy Paulios, the Wisconsin eBird reviewer, very handsomely provided me with directions to the territory. As is usually the case with Ammodramus, I heard the bird for quite a while before I finally tracked the little guy down singing from a weedy tassel (I'm no botanist so I don't know what this plant is.) I only got digiscoped pics through atrociously bad air, but you'll see the extensive rufous in the wings and the greenish wash on the lighter areas of the head. (In his sparrow ID workshop at the ABA Conference in Minot, Jon Dunn said it's like Henslow's had its head dipped in pea soup.) Another Ammodramus I heard and saw at the same spot was Le Conte's Sparrow. These guys have a really lemony-yellow wash to their head and an boldly striped back and crown. I didn't work on photos too hard since I already had some decent pics of the species. Very dapper birds, Le Conte's like it pretty moist underfoot. On my way to the Minot ABA conference I stopped at Chase Lake NWR near Jamestown. I was hoping to find a pre-conference Baird's Sparrow but struck out. I did have this mightily-buzzing Grasshopper Sparrow along a back road, though. They are more buffy overall but have yellow above and in front of the eye, plus a little on the leading edge of the folded wing. Their bodies are unstreaked and they have a prominent spot at the back of the auriculars (feathers behind and below the eye.) The second lifer Ammodramus I gleaned on this northern plains jaunt was Baird's Sparrow. Our field trip to Lostwood NWR turned up several, and I was happy to get scope looks along with all of the participants. I also really learned the song- nothing like hearing a bird sing (however softly) as you are watching it to gel up the audio-visual neural connections. After the conference was over I went back to the refuge on my own and found a stretch of the auto tour with 3 or 4 competing males in bushy clumps next to the road. The pics below were taken out my car window- don't forget the power of using your vehicle for a blind when possible (and safe.) This refuge is one of the best places in North Dakota to find this species due to their grassland management plan that included prescribed burns and grazing rotations that mimic bison foraging patterns- heavy for a while and then a few years of rest. Without fire, the grassland gets too brushy and wooded, and with over-grazing the grass gets too short. Unfortunately, over much of the Baird's Sparrow's historic range one or the other negative impacts has made the landscape unsuitable for this tidy little bird. Note the dark border on the back of the auriculars is thickest at the top and bottom rear corners, so from many angles it looks like the bird has two spots towards the back of the head. It also has a pale orange wash over the light parts of the head- Jon Dunn relates this to a wash in pumpkin juice. The 5th Ammodramus of my trip (and the last one possible without a detour of perhaps 1500 miles east, was Nelson's Sharp-tailed Sparrow (probably soon to be shortened by the AOU to just Nelson's Sparrow.) I heard these at several places in North Dakota, but for me this has always been a very difficult sparrow to see. First of all, it sings most at night, or in the dim dusk and dawn periods. Secondly, even when it is singing in daylight it is often well hidden in its preferred marshy sedges, reeds, or cattails. Its song is very short, thin and high pitched with a wheezy, hissed quality that makes directional locating and distance estimation a challenge. Also, since it likes such a marshy habitat it can be hard to approach without hip boots or a willingness to get pretty wet (and often a bad idea anyway from a habitat protection perspective.) Fortunately, though, the tour road at Lostwood NWR went through a low spot with marsh right up to the road's edge on either side. This was home to at least two Nelson's Sparrows (and a Le Conte's, and I was able to photograph a really orange-faced one out my car window. In my superficial little mind, this is my favorite Ammodramus for looks (on those rare occasions where you can see one well), but the poorest vocalist among an already weak-sounding bunch. Oh, and in the second pic I think you'll see how Sharp-tailed Sparrows got their name... Ammodramus Country: I'll guarantee there are 4 species of Ammodramus sparrows in this picture! (composite taken from the fire watch tower at Lostwood NWR.) Nelson's in the emergent marshy veg around the potholes, Le Conte's in the thickest, wettest grass right above the marshes, Grasshopper and Baird's up in the healthy, dryer native grasses.