1,018. Animals in a Trap

Shvisas Yom Tov 2:8

Even if one sets a trap for animals, birds or fish before yom tov, he should not take his catch on yom tov itself unless he knows for sure that it was caught before yom tov. If one makes a dam in a channel of water before yom tov, then he gets up early on yom tov and finds fish there, they are permitted because they were already trapped before yom tov began and therefore designated for use.

Shvisas Yom Tov 2:9

If a sealed building filled with produce that was designated for use became opened on yom tov, it is permitted to remove produce by way of the opening. If a person surveys fruit that was put out to dry on the day before yom tov in a Sabbatical year when produce is ownerless, he must make a mark and state that he will take produce from point X to point Y. If he doesn’t make a mark, he may not take produce.