At the beginning of chapter eight, Jem and Scout begin their walk to the Halloween festival on an extremely dark, warm October night. As they are walking past the Radley home, Scout mentions,
High above us in the darkness a solitary mocker poured out his repertoire in blissful unawareness of whose tree he sat in, plunging from the shrill kee, kee of the sunflower bird to the irascible qua-ack of a bluejay, to the sad lament of Poor Will, Poor Will, Poor Will. (Lee, 258)
Harper Lee utilizes symbolism by referring to the "solitary mocker" and the "bluejay" perching in the tree near the Radley home. The "solitary mocker" symbolically represents innocent, vulnerable beings like Jem and Scout, who are defenseless against Bob Ewell's attack later that night. The proximity of the mockingbird to Boo Radley's home is also significant. Boo Radley is a symbolic mockingbird throughout the novel and comes to Scout's and Jem's aid later that night. The bluejay is also symbolic of malevolent, harmful individuals like Bob Ewell, who is a threat to innocent, vulnerable children like Jem and Scout.
In addition to the symbolic significance of the "solitary mocker" and bluejay, this passage also foreshadows Bob Ewell's attack. The "blissful unawareness" of the mockingbird and the "irascible qua-ack" of the bluejay foreshadow the Finch children's unawareness of Bob Ewell's ambush on their walk home.