Monday, June 20, 2011

because why not

Jon recently found a Blue Grosbeak in Cass Co which I went over to look at this morning since it was about 20 minutes and 5 turns from my house. I've seen it once before in the state (not counting the probable flyby at Tiscornia this spring) but only a handful of other times. It seemed worth a couple hours even if it wasn't needed on any lists if for nothing else other than to get a look at the habitat and to get my ear in (and hey, they're not ugly).

I arrived before sunrise and had to wait awhile for it to get light out. I was mostly digi-scoping the bird since it didn't want to come very close to the road.

The bird would usually sing at the top of the shorter trees (the smaller 20 footers twice as high as the sumac) or at the mid to three-quarters height of the full size oaks etc that lined the railroad cut.

The two-tone bill always stands out to me in real life (including in flight) if the bird's in the sun.

Here's the habitat, looking SE down the tracks,

and looking NE:

Basically it looks like a lot of cut-over edges, a little lusher than the edges of the dune blow-outs, and more heavy on full size oaks behind the regenerating stuff than a lot of the woodlots around here, but otherwise didn't seem that specific to me. I always maintained when I lived in Washtenaw that County Farm Park looked pretty good for this species, and it looked a lot like the RR cut leaving the NE corner of the Dow Field in the Arb as well. I certainly see why the Boy Scout Campground at Warren Dunes turned up a bird for Andre last year.

Here's a sonogram of the bird. It was definitely grosbeak-pitched, but had more of a house or purple finch cadence. There were a couple orioles singing (including a probable Orchard) which could cause temporary confusion.

Here's a comparison sonogram I made of a Rose-breasted Grosbeak a few years ago:

The phrases of the Blue Grosbeak are shorter than the Rose-breasted's and are not as musical (remember the more horizontal the line on the sonogram, the longer the bird is holding one pitch, so the sweeter the song). The increased vertical aspects of the Blue Grosbeak give it the more finch like tones.

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