Some have the custom this Shabbat, which is called Shabbat Shira, to place food, seeds, wheat kernels, and the like in front of birds as a commemoration of the Midrash which states that the children of the Jewish nation fed seeds that grew from the trees inside the Red Sea to birds and these birds joined in Israel’s song of praise to Hashem. This custom is quoted in the works of the famous Poskim.
The Prohibition to Feed Ownerless Animals on Shabbat
At first glance, it would seem as though this custom is halachically unacceptable, for one may not feed any animal which one is not responsible to feed on Shabbat. It is thus prohibited for one to feed wild birds or animals, which are not one’s responsibility to feed, on Shabbat. Therefore, the Magen Avraham writes that this custom to feed birds wheat kernels on Shabbat Shira is a mistake and should be abolished. The Mishnah Berura (Chapter 324, Subchapter 31) rules accordingly.
One who nevertheless would like to observe this custom may do so by leaving a plate of seeds on the windowsill or anywhere else before the onset of Shabbat and birds will almost surely arrive on Shabbat morning to partake of these seeds. In this way, there is no prohibition according to all opinions.
The Reason for Leniency Where there is a Custom to do so
Nevertheless, Maran zt”l writes in his Sefer Livyat Chen (as well as in his Chazon Ovadia-Shabbat, Volume 3, page 24 and Volume 4, page 270 and on) that many of the great Acharonim question the words of the Magen Avraham and write that since this custom was enacted as a Mitzvah, one may indeed follow this custom on Shabbat Shira. The Sefer Tosefet Shabbat rules similarly. He proceeds to discuss several reasons for this leniency.
Maran zt”l also quotes the words of the author of the Sefer “Ohr Penei Moshe” who writes that the source for this custom is that in the times when the Bet Hamikdash stood, there was a container of “Manna” (a container which contained a small amount of the Manna which the Jewish nation ate in the desert) placed in the Bet HaMikdash in order to bring the Jewish people to a high level of trust in Hashem by showing that He feeds and sustains all of His creations just as He sustained our forefathers in the desert, every time they would see this container. Therefore, nowadays when this container is no longer accessible, for it was hidden shortly before the destruction of the Temple, it is customary to place seeds outside for birds to eat on Shabbat Shira, for on this Shabbat we read the Torah portion dealing with the “Manna”; this comes to show that just as birds find their food without toil and burden since Hashem cares for them, so too, if the Jewish people, who are compared to a bird, occupy themselves diligently with Torah study and Mitzvot and trust in Hashem, Hashem will provide them with sustenance in an easy and tranquil manner.
Maran zt”l quotes several additional sources for this custom and concludes by saying that based on the words of these Acharonim, those who customarily place seeds outside for birds to eat (even on Shabbat) have on whom to rely.
Feeding Stray Dogs on Shabbat
Maran zt”l continues to quote the words of the Meiri and other great Poskim who write regarding feeding a dog on Shabbat (this refers to a dog which does not belong to anyone, for if it does, the owner is certainly obligated to feed it on Shabbat) that one may feed it on Shabbat, for by doing so, one somewhat fulfills a Mitzvah as the Gemara says in Masechet Shabbat (155b) that the Torah made certain that dogs should have food, as the verse states regarding meat that was not slaughtered properly, “To the dog shall you throw it.” Thus, it is considered as though we are responsible for the dog’s sustenance and it is a Mitzvah to place food before it on Shabbat. The Magen Avraham rules likewise (although he rules stringently regarding feeding other ownerless animals even on Shabbat Shira, as we have written).
Feeding Animals that Cannot Obtain Food on Shabbat
Hagaon Harav Shlomo Zalman Auerbach zt”l adds that if one sees an animal on Shabbat that has nothing to eat, one may place food before it on Shabbat, as the verse states, “And His mercy is on all of his creations.” Although one is not responsible to feed this animal, nevertheless, if the animal is hungry and cannot find food anywhere else, one may feed it on Shabbat.
Summary: One may not feed wild animals or fowl that one is not responsible to feed on Shabbat. Thus, one may not feed undomesticated birds on Shabbat. Based on this, there are those who are stringent not to place seeds outside for birds to eat on Shabbat Shira. However, those who are lenient regarding this matter on this Shabbat, the day on which the Torah portions of the “Manna” and the splitting of the sea are read, and do this for the sake Heaven have on whom to rely. Similarly, one may feed a dog on Shabbat even if one does not own it.