Hypophthalmichthys molitrix (fish)

Ecology Distribution Management Info Impact Info References and Links Contacts

General Impact Burr et al. (1996) state that, "The potential impact of H. molitrix and A. nobilis (Aristichthys nobilis) is not adequately known. Markets for these carp apparently have not become well established. Confusion over the correct identity of these species and the legality of taking this fish in commercial harvests has resulted in its consideration as a nuisance by some fishermen we have interviewed." The Gulf States Marine Fisheries Commission (2003) states that, "H. molitrix are capable of consuming large quantities of phytoplankton. Nonetheless, potential effects of this species' introductions are difficult to assess. If stable breeding populations were to form and the number of individuals became abundant, shifts in food web structure could be expected. Although reported to consume mostly phytoplankton, and equipped with a highly specialized filtering apparatus, H. molitrix consume whatever form of plankton is available in its environment. Where phytoplankton is scarce this species will consume zooplankton (Spataru and Gophen, 1985; Burke et al. 1986). Spataru and Gophen (1985) have reported declines in zooplankton biomass which they attribute to stocked H. molitrix." The Gulf States Marine Fisheries Commission (2003) states that, "H. molitrix can transport diseases to new areas. Bocek et al. (1992) found this species to be an effective carrier of Salmonella typhimurium."          Location Specific Impacts: Lake Donghu (China)   Reduction in native biodiversity: In Asia, one of the worst DOCumented negative effects on fish biodiversity has resulted from within country translocations, for example in Donghu Lake, Wuhan, China when the introduction of grass carp resulted in the decimation of submerged macrophytes and the consequent ecological changes brought about an upsurge of Hypophthalmichthys spp. (Aristichthys nobilis) and silver carps (Hypophthalmichthys molitrix) and also the disappearance of most of the 60 fish species native to the lake (Chen, 1989) (Nguyen and Nakorn, 2004). Govind Sagar Reservoir (India)   Reduction in native biodiversity: The silver carp, H. molitrix was introduced to India in 1959. It was accidentally introduced into the Govind Sagar reservoir where it drastically reduced the populations of the native Catla catla and Tor putitora (Sethi et al UNDATED). Nepal   Reduction in native biodiversity: Exotic fish such as carp have been migrated into river systems and reservoirs of Nepal since their introduction in the rice paddies fish culture system. It is feared that in long run exotic may replace indigenous species such as golden mahseer, deep-bodied mahseer and many other endemic species (Shrestha, UNDATED).