First published in International Aquafeed, January-February 2016
The Latin names of some aquatic species can have fascinatingly obscure meanings that provide anyone in need of a hobby with hours of joyful investigation and speculation. The channel catfish is, alas, not one of them: Ictalurus punctatus simply means ‘spotty catfish’, and the briefest glance at one will tell you why.
Not everything about this species is so obvious, however. Although the US Fish and Fisheries Commission began collecting this species from its native Mississippi River Valley in the 1870s, it was 1890 before they got it to spawn in captivity, and only then did they realise the eggs were guarded by the male.
It would be a further 26 years before farmers discovered the productive gains to be had by providing the fish with a container to use as a nest. And only in 1929 was it understood that the male fish fanned their eggs for a reason, and that perhaps we ought to start doing so too.
Commercial aquaculture of this species wasn’t really considered economically viable until the end of the 1950s - over 80 years after collection and stocking first began.
Channel catfish have been widely introduced throughout the USA and abroad: mainly Russia, Latin America and China. Indeed, China now even exports a small amount of this fish back to its native country.
In the US and China, channel catfish are grown in ponds, tanks and raceways. Cages tend not to be used. The water needs to be warm; in some northern climes this is sometimes achieved using geothermal waters or even the heated waters coming from electric power plants.
Feed tends to be plant derived proteins, but vitamin supplements may be added, especially in indoor cultivation systems. Harvesting is done with wide-mesh seine nets so only fish of marketable size are taken.
Although currently popular across the US due to its image as a healthy food, the future market for channel catfish is uncertain, owing to competition from imported species.
Source: FAO
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