To court a mate or guard its territory, it gives a loud, screaming 'kee-aah', most often three or four times in a row.

Small Hunters · day 2 of 7
The screaming call is usually repeated three to four times.
He climbs high, then plunges in steep dives, spiralling and shooting back up after each one.
It drops directly onto its prey from the air.
Steller's jays and blue jays sometimes imitate the hawk's call.
They often keep the same nest for years, patching it up with fresh sticks every spring.
More about the Red-Shouldered Hawk
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