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AMERICAN CROW
This common statewide breeder took a newsworthy plunge due to West Nile Virus in recent years. 29 BCN eBird points sampled in both 2002 and 2003 had American Crow sightings during at least one of those years. The combined total for these 29 sites dropped from 43 in 2002 to 15 in 2003 - a decrease of over 65% in a one year period! However, the long term decline indicated by the data below does not accurately account for the many crows that breed in urban and agricultural areas which are insufficiently monitored. Although declines on the BCN Survey are starting to level out, spring and Christmas bird counts in the region continue to report record low numbers each year. Photo: © Eric Secker |
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Conservation Status | # of Points | # of Records | Credibility | Annual Change | Pct. Error | ||||||||||
None Noted | 258 | 1149 | Normal* | -26% | +/-4% | ||||||||||
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Steep Decline |
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Technical Details - Graph |
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Goodness of Fit Chi-Square: p= 0 |
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Fails |
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model fits if p >0.05 (model estimate is not significantly dif. from observed counts) |
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Copyright © 2008 Audubon - Chicago Region & Bird Conservation Network | ||||||
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