Boyd’s Bible Dictionary:

Many birds of Palestine similar to our own. The “speckled bird” (Jer. 12:9) means a vulture. Birds were snared (Psa. 124:7; Prov. 7:23; Amos 3:5). Used for curing leprosy (Lev. 14:2-7). List of birds not to be eaten (Lev. 11:13-19; Deut. 14:11-19).

Concise Bible Dictionary:

These are employed as symbols of evil agents: as, in the dream of Pharaoh’s baker, the birds ate the bakemeats he was carrying on his head (Gen. 40:17); and in the parable of the Sower the fowls or birds which devoured the seed by the wayside are interpreted by Christ to signify “the wicked one” (Matt. 13:4,19). In the parable of the Mustard Seed the kingdom of heaven becomes a great system with roots in the earth, under the protection of which the birds of the air find shelter (Matt. 13:31-32). The Greek is πετεινόν, the same in the two parables.