With three or four recently fledged young ones, parents have to stay ever-vigilant against threats. In this case, a Swainson’s hawk was cause for alarm and mama was keen on ensuring her little ones were safe.
I watched as she took off and chased the far-larger hawk off into the distance. She returned to the nest area but only had a brief respite as the hawk did another flyby. Here she is seen soon after launch as she flew overhead in hot pursuit.