sparrow hawk
鷂 centers on a specific bird of prey: the sparrow hawk. The meaning is narrow and refers to this particular raptor.
鷂 combines 䍃 (a phonetic component associated with the sound yō) with 鳥 (bird), forming a phono-semantic character for a type of hawk.
The left side 䍃 suggests the sound, and the right side 鳥 (bird) tells you it's a bird. Picture a sparrow hawk perched with the distinctive shape of 鳥.
For ヨウ, imagine a sparrow hawk letting out a sharp 'yō' cry as it dives: yō -> ヨウ.