This article does not have any sources. (July 2015)
Ghost nets are fishing nets that have been lost, or that have been been left by fishermen. These nets then float around in the sea, or they end up attached to a rock or other structure. This poses a problem, because the nets continue working. Fish and other animals get caught, and then starve, or die of other causes. Since most nets use plastic, they take a long time to decay. In addition, the nets may release toxic substances while they decay.