A retractable compact knife spear is provided. The knife spear may include a knife blade, as opposed to standard barbs and may be compacted to strap to a divers leg. The retractable knife spear may include other features, such as sound signaling devices and may be used as a pointer when leading dive teams. The retractable knife spear is useful for eradication of invasive fish species, such as the lion fish in the Caribbean and along the U.S. east coast.
