species of bird resembling quail
鴽 refers to a specific bird species that resembles a quail. Its meaning is narrow and descriptive rather than conceptual.
鴽 is a phono-semantic compound: 鳥 (bird) provides the meaning, and 如 likely contributes the sound. The character was created to name a specific quail-like bird.
The top 如 suggests the sound, and the bottom 鳥 shows it is a bird. Picture a quail-like bird whose call sounds like 'jo' (ジョ).
For ジョ, imagine a small quail-like bird named Jo: Jo -> ジョ, and the bird 鳥 sits under the sound 如.