Question: Is one permitted to move birds that live in a cage in order to move the cage from one place to another?
Answer: The Gemara in Masechet Shabbat (128b) states that animals or birds may not be moved on Shabbat and their law is equal to other objects which are Muktzeh and may not be moved on Shabbat.
The Ran writes that the reason why animals are Muktzeh on Shabbat and forbidden to be moved is because animals have no practical usage on Shabbat as nothing can be done with them; thus, their law is equal to wood and stones which are Muktzeh on Shabbat in and of themselves which may not be moved on Shabbat since there is no use for them. The Bet Yosef (Chapter 308) writes likewise.
The same Halacha applies to birds in a cage in that since the birds have no innate usage on Shabbat, it is forbidden to move them even when they are still in the cage. There is no distinction between moving animals or birds as Maran rules in his Shulchan Aruch (Chapter 308, Section 39), “One may not move domesticated animals, non-domesticated animals, or birds on Shabbat.”
Nevertheless, according to Rabbeinu Chaim Ohr Zarua (one of the great Rishonim) one may be lenient to move birds on Shabbat, for people enjoy their voices on Shabbat; this enjoyment does not entail any prohibition and there is likewise no prohibition to move them, for no forbidden work is being performed with them and one merely enjoys their appearance and chirping. Thus, according to this opinion, one may indeed move the birds in the cage on Shabbat. However, halachically speaking, we follow the ruling of the Rosh and Maran HaShulchan Aruch who rule that it is forbidden to move any animal or bird on Shabbat.
Maran Rabbeinu Ovadia Yosef zt”l writes (in his responsa Yabia Omer, Volume 5) that although we customarily rule stringently and prohibit moving birds on Shabbat in accordance with the ruling of the Rosh, nevertheless, in a situation where the prohibition of “making animals suffer” would apply, for instance, if the cage is in a place where the sun is beating down on it and the birds are in danger and suffering immensely, one may rely on the opinion of Rabbeinu Chaim Ohr Zarua and move the birdcage to a shaded area.
Moving a Dog on Shabbat
Based on the above it is clear that moving or carrying a dog on Shabbat is absolutely forbidden, even if not doing so causes the dog some distress, for a dog is Muktzeh like any other animal. Petting is permitted, however, for that is not considered moving.
Summary: One may not move animals or birds on Shabbat. For this reason, it is likewise forbidden to move a birdcage on Shabbat. However, when the birds are suffering, for instance, if the sun is beating down on the heads of the birds and this can sometimes cause them death or severe injury, one may move the birdcage to a more shaded area.
