Crebain

Crebain were a species of large black, crow-like birds native to both Dunland and Fangorn Forest in Middle-earth, that Saruman the White in Isengard used as spies after he joined forces with Sauron.
== Characteristics ==
Crebain were known to fly in large flocks resembling a huge black cloud and a big shadow cast below them. They made a horrible croaking, squawking noise when in flight which makes their presence known to all near them. Like crows and ravens, they seemed to possess at least some level of intelligence, though are not known to have spoken in known tongues. They were often used as spies by various evil powers. In the War of the Ring, flocks of Crebain were used by Saruman as spies to search for Frodo Baggins and the Fellowship, since he wanted the One Ring.