If, along the road, you chance upon a bird’s nest, in any tree or on the ground, with fledglings or eggs and the mother sitting over the fledglings or on the eggs, do not take the mother together with her young. Let the mother go, and take only the young, in order that you may fare well and have a long life. When you build a new house, you shall make a parapet for your roof, so that you do not bring bloodguilt on your house if anyone should fall from it.

That is that He commanded us to send away [the mother bird from] the nest. And that is His, may He be exalted, saying, "You must surely send away the mother, and the offspring take for yourself," (Leviticus 17:13). And the regulations of this commandment have already been explained in the last chapter of Chullin. (See Parashat Ki Tetzeh; Mishneh Torah, Ritual Slaughter.)

How must one send away the mother? He holds her by her wings and has her fly away. If he sent her away and she returned, he sent her away and she returned - even if this happens - four or five times, he is obligated to send her away, as [implied by the repetition of the verb in the] phrase: "You shall certainly send away."

[The mitzvah to] send away the mother bird applies only with regard to a kosher species of fowl that are not at hand, e.g., doves that rested in a dovecote or on a loft, wild fowl that nested in an orchard. [This is derived from the phrase (ibid.)]: "When you will chance upon." When, however, [fowl is] at hand, e.g., ducks, chicken, and doves that nested in a building, one is not liable to send away the mother.

[The following laws apply if the mother bird] was hovering [over the nest]: If her wings were touching the nest, one is obligated to send her away. If not, he is not obligated. If there was a cloth or feathers intervening between her wings and the nest, he must send her away. If he did not send her away, he is not liable for lashes.