Dead Crow Density, 2001

Map - Dead Crow Density [GIF image - 43 KB]
The Dead Crow Density map is also available as a Portable Document Format (PDF) file - 111 KB.

Summary 2001

No counties reached a high weekly dead crow density in 2001. The 5 boroughs of New York City and 4 surrounding counties reached moderate density during the weeks beginning: Bronx (6/3-6/10, 7/15, 7/29, 8/12-9/2); Brooklyn (6/3-6/10, 7/8, 7/29-9/16, 9/30); Manhattan (7/8, 7/29, 8/12-9/2, 9/30); Queens (5/13, 6/24, 7/22, 8/5-9/2); Staten Island (5/13, 6/3-6/17, 7/1, 7/15-9/2); Nassau (6/3, 7/8-9/30); Rockland (6/17, 7/8-7/29, 8/26-9/30); Suffolk (7/8-9/16); and Westchester (7/8-7/15, 9/2).

County Dead Crow Density*
Albany Low
Allegany Low
Bronx Low
Brooklyn Low
Broome Low
Cattaraugus Low
Cayuga Low
Chautauqua Low
Chemung Low
Chenango Low
Clinton Low
Columbia Low
Cortland Low
Delaware Low
Dutchess Low
Erie Low
Essex Low
Franklin Low
Fulton Low
Genesee Low
Greene Low
Hamilton Low
Herkimer Low
Jefferson Low
Lewis Low
Livingston Low
Madison Low
Manhattan Low
Monroe Low
Montgomery Low
Nassau Low
Niagara Low
Oneida Low
Onondaga Low
Ontario Low
Orange Low
Orleans Low
Oswego Low
Otsego Low
Putnam Low
Queens Low
Rensselaer Low
Rockland Low
Saratoga Low
Schenectady Low
Schoharie Low
Schuyler Low
Seneca Low
St. Lawrence Low
Staten Island Low
Steuben Low
Suffolk Low
Sullivan Low
Tioga Low
Tompkins Low
Ulster Low
Warren Low
Washington Low
Wayne Low
Westchester Low
Wyoming Low
Yates Low

*Dead Crow Sightings per Square Mile

Because reporting was interrupted by the events of September 11, it is not possible to interpret density levels in the NYC area. Low density may be an effect of decreased reporting, or environmental changes may have forced crows away from the area.

Note: Dead crow sightings are a possible early warning of, but not definitive confirmation of, West Nile virus activity. Crows die of many causes and reporting levels may vary among counties.

In 2000 an association was noted between the weekly dead crow density and human cases of West Nile virus. Dead crow density may provide, along with other surveillance indicators, a forecast of human WNV risk. No human cases occurred in counties with low weekly dead crow densities (less than 0.1 per sq. mile). Occasional human cases occurred within a few weeks after counties reported moderate dead crow densities. In the only county with a high dead crow density (greater than 1.5 per sq. mile), an outbreak of human cases began approximately two weeks later.