Left metal radical - the contracted left-side form of 金. Anchors 钓 in the metal hook used for angling. Many fishing-related characters share this radical because the hook, swivel and lures are metal. Same family: 钩 (hook), 锚 (anchor), 钉 (nail), 锈 (rust).
Right 勺 supplies the sound (sháo drifted to diào). The character itself depicts a ladle scooping liquid; here the curved shape also evokes a fishhook, giving a useful 'metal hook scooping fish out' mnemonic. Same phonetic family: 约, 的, 酌.
