These were put in Okanagan Lake in 1966 to help feed kokanee salmon, but the project backfired when it was found they compete with kokanee fry (babies) for food. The shrimp were found to be one of the main causes for the massive decrease in kokanee numbers, resulting in a ban on kokanee fishing in 1995.
The shrimp come to the surface at night and they breed prolifically. There could be millions throughout the south Okanagan lakes. There is a market for these shrimp (pet food, aquarium food etc). A Canadian company has been involved in trawler-fishing for the shrimp in Okanagan Lake and in 2005 harvested 10,100 kg. The industry is still in its infancy.
The fishing ban was lifted in June 2006 when limited fishing was permitted and strictly monitored by Ministry officials.