Question: I have birdcages in my possession and I must feed my birds on Shabbat. In order to feed them, I must open up the door of the cage, remove the dishes where the food and water are placed, fill them with food and water, and return them to their place in the cage. Does this pose any halachic concern of trapping on Shabbat?
Answer: In the previous Halachot we have discussed the basic laws of trapping on Shabbat. Included in these laws is if a bird enters a cage on Shabbat, one may not close the door behind it, for this would essentially be trapping it which constitutes a Torah prohibition. Let us now discuss our question.
First of all, the question must indeed be analyzed, for when the birdcage is opened, there are several moments when they can fly out and escape. When the door of the cage is later closed, this would seem to be “trapping” the birds once again.
Indeed, if we were discussing domesticated animals, such as sheep or goats, which generally do not escape from their owner’s immediate vicinity, this would not constitute a prohibition of trapping, for even with regards to chickens and ducks which return their cages/coops all the time we have written that the prohibition of trapping does not apply to them and one may close the door behind them (according to the opinion of Maran HaShulchan Aruch). This would then most certainly apply to sheep and goats (which do not revolt) that the prohibition of trapping does not apply to them, for they never try to escape from their owner. (If they happen to be difficult and constantly try to escape and the owner must strategically find ways to catch them, the prohibition of trapping would apply to them.) However, since we are discussing birds which certainly try to escape their entrapment, we must analyze whether or not the prohibition of trapping applies.
Indeed, Hagaon Rabbi Yishmael Ha’Kohen writes in his Responsa Zera Emet (Chapter 38) that although when the birds were in their cage originally they have already been trapped, nevertheless, since by opening the door of the cage undoes the previous trapping, one who comes and closes the door of the birdcage again has transgressed the prohibition of trapping on Shabbat. Other great Poskim write likewise (although there is a disagreement about this matter, see Chazon Ovadia –Shabbat, Part 5, page 104).
Only if at the time one opens the door of the cage does one stand and block the opening of the cage in a way that they birds would not be able to escape is there no prohibition of trapping by closing the door a second time. However, if there was even one moment that the birds had a chance to escape and then one closes the door once again, one transgresses the prohibition of trapping on Shabbat.
The Sefer Badei Ha’Shulchan advises bird sellers to make a double door for the cage such that even if one of the doors is opened, the second will stay closed. When one later opens the second door, the first will stay closed. Nevertheless, this idea will not work for those with small birdcages and they must do one of the following two things: Either they must provide enough food and water for the birds in the cage to last the entire Shabbat before the onset of Shabbat or the dishes of food and water may be remove on Shabbat being extremely careful that one’s hand is constantly blocking the opening of the cage so that the birds do not have an opportunity to escape. In this way one may indeed close the door of the cage again without concern. (If the door of the room where the birdcage is housed is closed, there is more room for leniency in certain situations, but unfortunately we cannot discuss this in detail.)
Summary: If one must feed caged birds on Shabbat, one may not open the door of the cage and then close it again, for this constitutes the forbidden work of trapping on Shabbat. One must therefore take care that his hand is blocking the opening of the cage the entire time it is open and it will then be permissible to close the door once again.