Metroid Database Bestiary

The Skreek is a strange creature evolved halfway between a bird and a reptile. 
This ambush predator lives in the lava, floating just beneath the surface where it can spot prey with its keen eyes. When it attacks, it will leap from the lava with the sudden, bloodcurdling cry that is its namesake. The Skreek can catch prey using its toothed beak or paralyze it from a distance by spitting a poisonous blob.

The Skreek appears in only one cave, but since they appear alongside the Drivel, they can be difficult to dodge. The blobs they spit deal only a small amount of damage, but contact with the Skreek will deal a large amount of damage. Since Skreeks will leap suddenly from the lava, move through this area cautiously and clear out the Drivels to gain room to maneuver. Drops large energy balls.

The Japanese name is “Kreek” (クリーク), or “Kureek”, an onomatopoeic sound for a screech, and presumably the sound they make.