COOPER'S HAWK

Cooper
Copyright © 2005 Eric Secker

Conservation Concern: NONE

Population Trend: Poorly Known
Credibility: Poor

The Cooper's Hawk is an uncommon breeder in the CW Region. This species, once common throughout Illinois, was placed on the endangered species list in the late 1970's, but has since rebounded considerably and was delisted in 1999. Short term data is too sparse to produce an accurate trend, but long term data shows a considerable increase in population size since 1988. This species has also adopted very well to residential areas in NE Illinois - poorly sampled by the BCN Census.

Trend Level

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Avg. Yearly
Rate of Change:

The vertical axis numbers represent an index of the population change.

Note that the scales may vary between graphs.

Avg. Yearly
Rate of Change*:

-9%

16%

Technical Notes (1997-2004 Trend)

Sample Size (Indiv.): 23

Sample Size (Records): 20

AVG. YEARLY RATE OF CHANGE:
(including standard error)
-53 to 35

GOODNESS OF FIT:
Chi-square: 37.39, df 34, p 0.3162
Likelihood Ratio: 29.51, df 34, p 0.6876
AIC: -38.49
NOTE: (model fits if p values are above 0.05)

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1997-2004 Trend Point Count Data	1988-2004 Trend* All Observation Types