הלכה על חולין 278:9

From the laws of the commandment is that which they, may their memory be blessed, said (Chullin 139b), "'If you chance upon a bird's nest in front of you on the path' - just like the path which is not acquired by you; so too all, etc. From here they said, 'Doves from the coop and doves from the attic that nested in cubicles and in edifices, and geese and chickens that nested in an orchard, [one is] obligated in sending away; but [if] they nested within the house, and also Herodian doves, [one is] exempt from sending away. [... And] Rav Yehudah ... said, '[If] he found a nest in the sea, [he is] obligated in sending away,'" as it is included in the expression, 'on the path,' "as it states (Isaiah 43:16), 'So said the Lord, who makes a path in the sea.'" And (Chullin 12:3) "[If] it was flying - [... if] its wings do not touch the nest, one is exempt from sending. [... If] there were [...] damaged eggs, one is exempt from sending, as it states (Deuteronomy 22:6), '[...] young birds or the eggs' - just as young birds are viable, so too [the] eggs [must be] viable [to fall under the law...]. If one sent her away and she returned, [...] - even [several] times - one is obligated [to send her away again], as it states (Deuteronomy 22:7),' You shall surely send.'" And the rest of the details of the commandment are elucidated in the last chapter of Chullin.