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,
Jellynose fish Jellynose fish The jellynose fishes or tadpole fishes are the small order Ateleopodiformes. This group of ray-finned fish is monotypic, containing a single family Ateleopodidae. It has about a dozen species in four genera, but these enigmatic fishes are in need of taxonomic revision. The scientific name means ""Ateleopus"-shaped", from "Ateleopus" (the type genus) + the standard fish order suffix "-formes". It ultimately derives from Ancient Greek "atelís" (ἆτελής, "imperfect") + "pús" (πούς, "foot") + Latin "forma" ("external form"), the Greek part in reference to the reduced pectoral and ventral fins of the jellynoses. Jellynoses are deep-water, bottom-dwelling, marine fishes.