No, it's not your imagination. There really are a lot more hawks, falcons and other raptors passing overhead these days.
We may not think of the common California turkey vulture as a raptor, but Alan Fish explains that they are part of that same avian family.
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The Golden Gate Raptor Observatory studies raptors that are migrating or stay year long in the Marin Headlands near the golden gate. San Francisco bay has the largest amount of raptors west of Texas.
The Golden Gate Raptor Observatory has demonstrations and observation information on their website , or call 415-331-0730 for more information.