Monday, June 4, 2012

Savannah Sparrow and Other Increasingly Rare Grassland Birds

In 2007, Savannah Sparrows were still common in our area 
Many of our native songbird populations are declining in the Northeast; this is particularly true with the grassland birds. In fact, in the last 20 years, populations of most grassland species seem to have fallen off a cliff.

The Eastern Meadowlark seems to be found only in the northern part of our County
Eastern Meadowlark, Grasshopper Sparrow, Vesper Sparrow, Horned Lark and Upland Sandpiper are now rarely found during the breeding season.

The Upland Sandpiper is one of the rarest grassland birds
The Savannah Sparrow, which only 5 years ago, was a common nesting species, has abruptly disappeared from its former haunts. Of the common grassland birds, now only the Bobolink manages to hang on. This is due to the fact that they are able to tolerate fields that are somewhat overgrown. But even the Bobolink’s days as a resident breeder are numbered –that is unless widespread conservation management plans are implemented.

Corn is definitely king in our region. These days just about every field is planted with corn, and those that aren’t are planted with another row crop –soybeans. The problem with these crops is that they make terrible bird habitat. In fact none of the grassland birds that I mentioned above can breed in these fields.
The Bobolink still hangs on at our nature preserve
Hay fields are for the most part, ideal for grassland birds to breed in, but they are becoming harder to find as most have either been converted to corn fields, or have been left fallow and have filled in with trees and shrubs. Another problem is that the vast majority of the few remaining hay fields are mowed far too early in the season, so that that grassland birds can’t finish their nesting cycle before the tractors come in. Pastureland is also becoming hard to come by, but since it tends to be grazed and not mowed, grassland birds can still find a haven in these fields. Pastureland, mostly in the northern parts of our Oneida County, can still host a healthy array of grassland species.

The Savannah Sparrow collects food for its young

The Savannah Sparrow resembles the much more common Song Sparrow, but the Savannah Sparrow’s striped plumage is more sharply defined. Unlike the Song Sparrow, the Savannah usually shows some yellow at the base of its bill and over its eye. The song of the Savannah Sparrow starts with a few chip notes and is followed by 2 longer buzzy notes that have a sizzling quality to them. In the old days (only 5 years ago), the breeding grounds of this sparrow commonly sounded like they were sizzling in the sun. At Spring Farm, the Savannah Sparrow  nested around our upper horse pastures and in several of the nature preserve’s old fields. Nests of the Savannah are placed on or near the ground, which makes them vulnerable to predators and obviously, to farm equipment.

The Grasshopper Sparrow singing in our field back in 2000
Wilson's Snipe is another species that appreciates grasslands

About the only other truly grassland species that we’ve ever had nesting at the nature preserve was the Grasshopper Sparrow. A small colony of this small, short tailed species last nested in our largest field back in 2000. Their song is similar to the Savannah Sparrow, but consists of a few chip notes followed by sizzling buzz. As the big field’s grasses were overtaken with goldenrod, asters and other rigorous perennials, the Grasshopper Sparrow was displaced. 

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