It is narrated from Sayyiduna Zayd bin Khalid al-Juhani (may Allah be pleased with him) that a man came to the Prophet (peace and blessings be upon him) and said: O Messenger of Allah, what do you say about a stray camel? At this he (peace and blessings be upon him) became angry and his (peace and blessings be upon him) cheeks turned red, and he (peace and blessings be upon him) said: "What have you to do with it? It has its feet and its water-skin with it; it eats from the trees and drinks water until its owner finds it."
He said: What is the ruling on a stray sheep? He (peace and blessings be upon him) said: "It is for you, or for your brother, or for the wolf."
He said: What is the ruling on a found item (luqatah)? He (peace and blessings be upon him) said: "Take note of its bag and the cord it is tied with, then announce it. If it is not identified, mix it with your own wealth."
Hadith Referenceالمعجم الكبير للطبراني / باب الزاي / 5237