Abstract: Control of stickleback, sucker, carp and bullhead catfish is accomplished by adding to their aqueous habitat a compound containing diethyl esters of phosphoric, phosphorous, thiophosphonic and thiophosphorous acid that contain a chloride or a chlorinated or vinyl group.

Abstract: Mussels and related bottom dwelling creatures may be eliminated from an underwater bed by applying to the zone of at least the bottom 2 feet of water above the bed water-soluble sulfite salt such as sodium metabisulfite to substantially deplete dissolved oxygen in the zone. Thereafter, hydrogen sulfide may be directly added to the zone, being stabilized by the absence of oxygen therein the enhance the mussel kill. Thereafter, as fresh water is added to the zone, the hydrogen sulfide and residual sulfites are oxidized to relatively harmless sulfates.

Abstract: The growth of sea urchin eggs is inhibited with a composition comprising a methine dye having a reduction potential equal to or more negative than -1.0 volt which is capable of being absorbed by the eggs, and an inert liquid carrier.

Abstract: Control of stickleback in streams and other locales is achieved by selective addition of chemicals that form free azide radicals in water, specifically sodium azide and potassium azide. Subsequent deactivation, when desired, is achieved by addition of calcium compounds. High selectively to stickleback can be achieved with minimal risk to desirable game fish in the salmon and trout groups.