peregrine falcon: see falcon.

or duck hawk

Falcon species (Falco peregrinus) found worldwide but rare today because of bioaccumulation of pesticides. Peregrines are 13–19 in. (33–48 cm) long and gray above, with black-barred whitish underparts. They fly high and dive at tremendous speed (up to 175 mph, or 280 kph—the greatest speeds attained by any bird), striking with clenched talons and killing by impact. They usually nest in a scrape on a high cliff ledge near water, where bird prey is plentiful. Breeding programs have reintroduced the species into the wild and introduced it into urban areas, where it finds a clifflike habitat among skyscrapers and preys chiefly on the rock dove (see pigeon). Despite the programs' success, the species remains vulnerable.

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