Peregrine falcons use a wide variety of vocalizations at different stages of life, but primarily during breeding seasons.

Most vocalizations are either between mated individuals, parents and offspring, or in antagonistic interactions.

Young beg for food with a call similar to: "screea, screea, screea."

"Cack" calls are usually used in alarm and nest defense. They are highly individual specific, with individual recognition possible in 72 to 90% of calls. The call is characterized as "kaa-a-aack, kaa-a-ack."

"Chitter" calls are used in several contexts and are a rapid succession of "chi chi chi chi's." Similarly, the eechip call occurs in a variety of contexts. It is characterized as "kee-u-chip", but the "chip" portion contains the highest energy and the "kee-u" portion is often left out.

When hunting, peregrine falcons will often give sharp, territorial calls in quick succession, "kee, kee kee...".

Postures are used to communicate aggression and appeasement. Raising the feathers and bill gaping are typical of aggressive posturing. Submission is indicated by the feathers being held tight to the body and the head held down, with beak averted.

Peregrine falcons have extraordinarily keen vision. They can see small objects from very far away and accurately fly at high speeds to capture them.

Communication Channels: visual ; acoustic