Electropositive shark repellent Atlantic longlining vessels in 2008. As expected, teleosts (bony fish) are not repelled by the electropositive metal’s cation liberation in seawater. This is because teleosts lack the ampullae of Lorenzini. Teleost response was confirmed using captive Cobia ("Rachycentron canadum") and Pacific halibut ("Hippoglossus stenolepis"). In July 2008 swordfish ("Xiphias gladius") catch was reported on experimental hooks treated with electropositive metal. As with all shark repellents, 100% effectiveness will not be achieved with electropositive metals. The metals are particularly effective when the shark is relying on its electrosense. It is likely that electropositive metals are ineffective for deliberately stimulated (chummed) sharks,
Flat pebblesnail Flat pebblesnail The flat pebblesnail ("Lepyrium showalteri") is a species of freshwater snail, an aquatic gastropod mollusk in the family Lithoglyphidae. This species is endemic to the United States. This snail has been listed as endangered on the United States Fish and Wildlife Service list of endangered species since October 28, 1998. "Lepyrium showalteri" is the only species in the genus Lepyrium. "Lepyrium showalteri" is the type species of the genus "Lepyrium". Lepyriidae is a synonym of Lithoglyphinae. The flat pebblesnail is a small snail in the family Lithoglyphidae; however, the species has a large and distinctive-looking shell. This snail's