The Oral Talmud with Benay Lappe and Dan Libenson Episode 84

MISHNA: With regard to a dove chick [nippul] that was found within fifty cubits of a dovecote, it belongs to the owner of the dovecote. If it was found beyond fifty cubits from a dovecote, it belongs to its finder. In a case where it was found between two dovecotes, if it was close to this one, it belongs to the owner of this dovecote; if it was close to that one, it belongs to the owner of that dovecote. If it was half and half, i.e., equidistant from the two dovecotes, the two owners divide the value of the chick.

GEMARA: ... We learned in the mishna: With regard to a dove chick that was found within fifty cubits of a dovecote, it belongs to the owner of the dovecote. And as the mishna does not make a distinction between different cases, it indicates that this is the halakha even though there is another dovecote that is larger than the proximate one in terms of number of birds. This shows that closeness, not majority, is the determining factor. The Gemara answers: This is referring to a case where there is no other dovecote in the area. The Gemara asks: If so, say the latter clause of the mishna: If it was found beyond fifty cubits from a dovecote, it belongs to its finder. And if there is no other dovecote in the area, it certainly fell from that dovecote. How, then, can it be given to the finder?

The Gemara answers: With what are we dealing here? We are dealing with a chick that hops from place to place but does not yet fly. As Rav Ukva bar Ḥama says: With regard to any creature that hops, it does not hop more than fifty cubits. Consequently, any bird found within fifty cubits of a dovecote is assumed to have come from there. Rabbi Yirmeya raises a dilemma: If one leg of the chick was within fifty cubits of the dovecote, and one leg was beyond fifty cubits, what is it? The Gemara comments: And it was for this that they removed Rabbi Yirmeya from the study hall.