One of India’s most celebrated ornamental fishes, the Denison barb has suffered huge declines as a result of its popularity. In the absence of catch limits, the single most significant threat to this species is unsustainable collection for the pet trade. It has declined at an alarming rate of around 70 percent since 2004 and is now reduced to highly fragmented, relict populations (1) (3) (4) (8).
This species was first exploited in 1996, when India began exporting it to Europe, with demand for the species rapidly increasing thereafter. Between 2007 and 2008 alone the Denison barb accounted for 65 percent of ornamental fish exports from India, with the value of this trade worth around US$ 1.5 million (7).
These fisheries have been highly selective for the more attractive juveniles, limiting the number of fish reaching an age at which they can reproduce, while they may have also inadvertently caused a sex ratio skewed towards males, and reduced the species’ genetic diversity (1) (9). Those remaining populations are further threatened by deforestation, mining, agriculture, hydroelectric projects and urban expansion, all of which reduce water quality, and the degradation of habitat by the use of dynamite fishing and plant poisons for larger fish species (1) (7).