Figure 3 (above): Total hours per year. The trend in this case is significantly upwards, although it will probably level off in the future.
Figure 4 (above): Yearly passage rates (birds/100 hours) for the following species: Osprey, Sharp-shinned Hawk, Merlin, and Peregrine Falcon. Trend lines are not significant.
Figure 5 (above): Yearly totals, predicted totals, and the ratio between the two for the following species: Osprey, Sharp-shinned Hawk, Merlin, and Peregrine Falcon. Ratio values well below 1 may indicate a declining population.
Hawk Migration Charts
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