Q. See questions above. If the bird cage usually hangs from a stand that is too high for the kids to reach and throw the seeds inside. Can it be lowered to the ground on Shabbat and then placed back?
A. Shemiras Shabbos K. (27: n.31) maintains that the cage is Muktza as it is a ‘Bosis’ or a base for the birds it contains and therefore should be regarded as Muktza as the birds are. This is similar to the fish tank mentioned in a prior question. He quotes Horav S.Z. Auerbach zt’l that this applies even if the birds fly constantly and may not be standing on the cage the complete Bein Hashmoshos (time between day and night).
Therefore, Horav Shlomo Miller’s opinion is that the cage should be lowered before Shabbos begins and left at a height accessible to the children.
Rabbi A. Bartfeld as advised by Horav Shlomo Miller, Horav Dovid Pam and Horav Aharon Miller Shlit’a