For the source text click/tap here: Bava Batra 23
To download, click/tap here: PDF
The Mishnah rules that the maximum range of movement of a young dove is up to fifty amos from its dovecote. This was determined by our sages.
Therefore, any dove found within a fifty-amos radius of a dovecote must be assumed to belong to the owner of the dovecote, and it should be returned to him.
The Gemara asks: Must one distance a dovecote only fifty cubits from the city and no more?Is that as far as one can expect a dove to fly? And the Gemara raises a contradiction from a mishna (Bava Kamma 79b): One may spread out traps [neshavin] for doves only if this was performed at a distance of at least thirty ris, or four mil, which is eight thousand cubits, from any settled area, to avoid catching birds that belong to another.
Apparently, doves fly a distance of thirty ris, whereas the mishna here states fifty cubits.
We explore the biology phylogeny and use of the dove as a metaphor in antiquity as well as in Tanach.