Sahih Bukhari Volume 3, Book 45, Hadith 2430

حَدَّثَنَا عَبْدُ اللَّهِ بْنُ يُوسُفَ، أَخْبَرَنَا مَالِكٌ، عَنْ رَبِيعَةَ بْنِ أَبِي عَبْدِ الرَّحْمَنِ، عَنْ يَزِيدَ، مَوْلَى الْمُنْبَعِثِ عَنْ زَيْدِ بْنِ خَالِدٍ ـ رضى الله عنه ـ قَالَ جَاءَ رَجُلٌ إِلَى رَسُولِ اللَّهِ صلى الله عليه وسلم فَسَأَلَهُ عَنِ اللُّقَطَةِ‏.‏ فَقَالَ ‏"‏ اعْرِفْ عِفَاصَهَا وَوِكَاءَهَا، ثُمَّ عَرِّفْهَا سَنَةً، فَإِنْ جَاءَ صَاحِبُهَا، وَإِلاَّ فَشَأْنَكَ بِهَا ‏"‏‏.‏ قَالَ فَضَالَّةُ الْغَنَمِ قَالَ ‏"‏ هِيَ لَكَ أَوْ لأَخِيكَ أَوْ لِلذِّئْبِ ‏"‏‏.‏ قَالَ فَضَالَّةُ الإِبِلِ قَالَ ‏"‏ مَا لَكَ وَلَهَا، مَعَهَا سِقَاؤُهَا وَحِذَاؤُهَا، تَرِدُ الْمَاءَ وَتَأْكُلُ الشَّجَرَ، حَتَّى يَلْقَاهَا رَبُّهَا ‏"‏‏.‏

Narrated By Zaid bin Khalid : A man came and asked Allah's Apostle about picking a lost thing. The Prophet said, "Remember the description of its container and the string it is tied with, and make public announcement about it for one year. If the owner shows up, give it to him; otherwise, do whatever you like with it." He then asked, "What about a lost sheep?" The Prophet said, "It is for you, for your brother (i.e. its owner), or for the wolf." He further asked, "What about a lost camel?" The Prophet said, "It is none of your concern. It has its water-container (reservoir) and its feet, and it will reach water and drink it and eat the trees till its owner finds it."