No one has seen a flock of birds like this in years, he thought.

They look like a flock of birds taking off from the bottom.

The great hall was filled with a flock of birds.

A flock of birds might drive a powerful animal away from food.

Finally you spot something coming south, but it's a flock of birds.

A flock of small black birds came across the building in a desperate way.

It would be like a flock of birds in flight.

They are usually found in small flocks of less than ten birds.

What looked like a flock of birds rose from deep in the city and headed our way.

High in the air there were flocks of dark birds.