Human Interactions
Harmless to humans, the cloudy catshark adapts well to captivity and has reproduced in the aquarium. It is often used as a model organism in physiology research. On September 25, 1995, Masuda Motoyashi and colleagues used this species to perform the first successful artificial insemination of a shark or ray. The cloudy catshark is caught incidentally by commercial fisheries with bottom fishing nets including trawls and gillnets, as well as on bottom longlines. Captured individuals are typically discarded, possibly with a high survival rate due to their hardiness. Some 40% of the fish discarded in Yamaguchi Prefecture fisheries are of this species. The bottom trawl fishery operating off Fukushima Prefecture may catch over a ton of cloudy catsharks annually, which are also discarded.
Despite heavy fishing pressure within its range, the cloudy catshark remains common, perhaps because it may be more biologically productive than most other sharks. As a result, it has been assessed as Least Concern by the International Union for Conservation of Nature (IUCN). Cloudy catsharks from a number of locations off Japan have been found to be contaminated with polychlorinated biphenyls (PCBs) and dichlorodiphenyldichloroethylene (DDEs), which they acquire from their food. One likely source of these pollutants is the use of the pesticide DDT by developing nations in southern Asia.
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