Journey North Red-winged Blackbirds

Red-winged Blackbird

Neighborhood Watch: How Redwings Protect Their Babies

Advantages to Redwings chasing crows:

This may keep crows from noticing nests.
One redwing can help protect the nests of dozens of other redwings.
Even after crows have noticed the nests, the size and strength of a redwing can drive a crow away.

Disadvantages

Sometimes if a redwing isn't careful, it can get hurt by bonking into the crow or being attacked.
During the time the redwing is chasing the crow, it can't be feeding or finding food for its babies.
Other dangerous nest predators, like snakes and cats, might sneak in while the redwing is off chasing crows.