Conversation so far:
what kind of bird was in mall cop 2
The bird that attacks Paul Blart in Mall Cop 2 is a Grey Crowned Crane.
how big are grey crowned cranes
The grey crowned crane is about 1 m tall, weighs 3.5 kg, and has a wingspan of 2 m.

Question: how heavy are the birds
Self-contained rewrite: how heavy are grey crowned cranes