Fishing net
A fishing net or fish net is a net used for fishing. Fishing nets work by serving as an improvised fish trap, and some are indeed rigged as traps. They are usually wide open when deployed, and then close off when retrieved to engulf and trap fish and other aquatic animals that are larger than the holes/gaps of the net, as well as many unwanted bycatches due to the underwater area a net can cover.
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