Monday, August 05, 2013

Swamp Sparrow

Swamp Sparrow - Melospiza georgiana

Until July 30th, I had no idea that Swamp Sparrows nested close to my customary hike. At the far end of the Glenmore Runoff Reservoir there is a marshy area where ducks nest. I can just see this area with my binoculars but usually the birds are too far away for me to identify. The western shore is a dense forest and until July 30th, I never attempted to bushwhack through this area. Took me 1.5 hours to circumnavigate the reservoir and most of this time was spent threading my way through brush so dense there were no deer trails. The reservoir bends into a narrow area lined with cat-tails and bull rushes that is not visible from the distant vantage point along my customary walk. The air was thick with humidity and bugs. The water was still and shallow. Swampy. Made perfect sense to see these sparrows.
Swamp Sparrows are double brooded and build their nests about a foot off the ground in the grass or cat-tails that surround marshy areas. The reservoir water rose only modestly with the flood, which I hope, allowed their first brood to survive. 
These sparrows eat more insects than seeds and their jaw muscles are less well developed and their bills are smaller than other Melospizza species such as the Song and Lincoln Sparrows.The legs are longer, which allows the Swamp Sparrow to wade in shallow water. 
References

The Atlas of Breeding Birds of Alberta. Federation of Alberta Naturalists. 2007.

Baicich PJ, Harrison CJO. Nests, Eggs, and Nestlings of North American Birds. Princeton UP. 2005.

Beadle D, Rising J. Sparrows of the United States and Canada. Princeton UP. 2003.

Fisher C, Acorn J. Birds of Alberta. Lone Pine Publishing. Edmonton. 1998.

Sibley David A. The Sibley Guide to Birds. Alfred A Knopf, Inc. New York. 2000.

Sibley David A. The Sibley Guide to Bird Life and Behavior. Alfred A Knopf, Inc. New York. 2001.

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