Did you know there were once birds called passenger pigeons?
They always flew in huge groups.Some groups were so hude that it took three days for them to pass overhead!
In the early19th century, there were as many as five billion passenger pigeons.One hundred years later however,they all disappeared.
What happened to them?European immigrants to America killed them for food and pleasure.They believed there would always be plenty of
passenger pigeons.So they kept catching them until it was too late to save them.