January 30, 2011 : Snakeheads

Snakeheads

Snakeheads (Channidae) are a family of freshwater fish native to Africa and Asia. These predatory fish are distinguished by a long dorsal fin, large mouth and shiny teeth. They have a physiological need to breathe atmospheric air, which they do with a suprabranchial organ: a primitive form of a labyrinth organ. There are two extant genera, Channa in Asia, and Parachanna in Africa, consisting of 30-35 species.

They are considered valuable food fish. Called Ca Loc, ca Qua, or Ca Chuoi in Vietnamese, it is prized in clay pot dishes and pickled preparations. Larger species like Channa striata, Channa maculata, and Parachanna obscura are farmed in aquaculture. Snakeheads feed on plankton, aquatic insects, and molluskscarp, or frogs. In rare cases, small mammals such as rats are taken. The size of the snakehead species differs greatly. "Dwarf snakeheads" like when small. When adult, they mostly feed on other fish like Channa gachua grow to 10 inches (25 cm). Most snakeheads grow up to 2 or 3 feet (60–90 cm). Only two species (Channa marulius and Channa micropeltes) can reach a length of more than 1 meter and a weight of more than 6 kg.

It is illegal to keep snakeheads as pets in all states of the U.S. and other countries as they have become an invasive species due to individuals releasing them into the wild. In the U.S., National Geographic referred to snakeheads as "Fishzilla."

When the Snakehead eats it is a thrust predator. It will eat its prey all at once, striking and ingesting it whole.

The giant snakehead (Channa micropeltes) is native throughout Asia, and is the most aggressive Snakehead. They can grow to around 1 meter in length. Adult Snakeheads force their young to breathe air by pushing them to the surface.

From 2002 to 2003, one Los Angeles supermarket was found to have sold approximately 25,000 dollars worth of illegal live Snakeheads which caused breakouts in local ecosystems.