Boyd’s Bible Dictionary:

(diver). Clean by the law and offered as a sacrifice by the poor (Gen. 15:9; Lev. 5:7; 12:6-8; Luke 2:24); symbol of innocence (Matt. 10:16); harbinger of God (Gen. 8); emblem of Holy Spirit (Matt. 3:16).

Concise Bible Dictionary:

The well-known bird of the pigeon tribe, of which there are many species. These words are translated both “dove” and “pigeon.” For the turtle-dove the words tor, τρυγώνv, are used, names supposed to be derived from the note of the bird. Pigeons are very common in Palestine, and if any persons were too poor to buy a pair for an offering the young could easily be caught in the holes of the rocks: thus God graciously ordered it that the poorest could obtain what was needed.
There are four species of doves that inhabit Palestine: of these the most abundant is the Rock Pigeon, or Blue Rock Dove, the Columba livia. They shun the habitation of man, and live in holes in the rocks. There are three species of turtle doves known in Palestine, which are both wild and domesticated. Some may often be seen in Jerusalem. The most abundant of these is perhaps the Turtur auritus.
Columba Livia
The dove is commonly taken as the emblem of peace: the Holy Spirit descended on the Lord “like a dove,” answering to “on earth peace, good will toward men.” It is also an emblem of harmlessness: “wise as serpents, harmless as doves” (Matt. 10:16). In the Song of Solomon the bridegroom three times calls the bride “my dove,” and says she has “doves’ eyes”; she also says the latter of him (Song of Sol. 1:15; Song of Sol. 2:14; Song of Sol. 4:1; Song of Sol. 5:2,12; Song of Sol. 6:9). Loving gentleness characterizes the dove.
Eurasia Collared Dove – Streptopalia Decaocto