ML647261848

媒体文件注释

Agitated call signaling the presence of a Red-tailed Hawk nearby.

观察细节

Mobbing two RTH (see Red-tailed Hawk for more details and pics). The first Raven flew out of a treetop calling agitatedly (recording). It targeted an immature RTH on a nearby tree. As the hawk evaded the attack very skillfully and refused to move away, a second Raven came to help the first (pics 3-7). Yet again, the hawk showed an impressive ability to withstand the combined harassment (even when "sandwiched in," pic 7), at which point one of the Ravens switched to physical violence (pics 8-9). As if this had been a crossing the line of sort, a second RTH arrived to join the fray. The Ravens split their attention to each of the hawks and all four birds drifted out of our view. A couple of minutes later, however, the immature hawk returned exactly where it was at the beginning of the encounter. A Raven showed up shortly after but appeared to give up on its effort to dislodge its opponent.

额外物种

• Black-capped Chickadee Poecile atricapillus
• House Finch Haemorhous mexicanus