Pitt says in Mecca no one will kill the blue pigeons, because they are held sacred.
The black pigeons of Dodona. Two black pigeons, we are told, took their flight from Thebes, in Egypt; one flew to Libya, and the other to Dodona, in Greece. On the spot where the former alighted, the temple of Jupiter Ammon was erected; in the place where the other settled, the oracle of Jupiter was established, and there the responses were made by the balck pigeons that inhabited the surrounding groves. This fable is probably based on a pun upon the word pelciai, which usually means “old women,” but in the dialect of the Epirots signifies pigeons or doves.
Mahomet's pigeon. (See Mahomet.) In Russia pigeons are not served for human food, because the Holy Ghost assumed the likeness of a dove at the baptism of Jesus; and part of the marriage service consists in letting loose two pigeons. (See The Sporting Magazine, January, 1825, p. 307.)
Pigeon lays only two eggs. Hence the Queen says of Hamlet, after his fit he will be-
As patient as the female dove When that her golden couplets are disclosed [i.e. hatched].
Hamlet, v. 1.
He who is sprinkled with pigeon's blood will never die a natural death. A soulptor carrying home a bust of Charles I. stopped to rest on the way; at the moment a pigeon overhead was struck by a hawk, and the blood of the bird fell on the neck of the bust. The sculptor thought it ominous, and after the king was beheaded the saying became current.
Flocks of wild pigeons presage the pestilence, at least in Louisiana. Longfellow says they come with “naught in their craws but an acorn.” (Evangeline.)
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894