Siamese Fithing Fish

 

The Siamese fighting fish, also sometimes colloquially known as the betta (Betta splendens), is a species in the gourami family which is popular as an aquarium fish. This species is native to the Mekong basin of Thailand, Laos,Cambodia, and Vietnam, where it can be found in standing waters of canals, rice paddies, and floodplains. They are called pla-kad (biting fish) in Thai or trey krem in Khmer. They tend to be rather aggressive.

 

 

Description

B. splendens usually grows to a length of about 6.5 cm (2.6 in). Although aquarium specimens are known for their brilliant colors and large, flowing fins, the natural coloration of B. splendens is a dull green, browns, and gray, and the fins of wild specimens are relatively short.

 

Diet

Siamese fighting fish have upturned mouths and are primarily carnivorous surface feeders, although some vegetable matter may be eaten. In the wild, they feed on zooplankton, crustaceans, and the larvae of mosquitoes and other water-bound insects.

 

Reproduction and early development

 

 

 

 

 

 

 

                                                                       A pair spawning under a bubble nest in a breeder's tank

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

                 One-day-old larvae in a bubble nest, their yolk sacs have not yet been absorbed: Betta fry rely entirely on their gills to breathe.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

                    A 15-day-old, free-swimming fry is infected with Piscinoodinium sp. (velvet disease), a common killer of betta fry in captivity.

 

Male bettas flare their gills, twist their bodies, and spread their fins if interested in a female. The female darkens in colour, then curves her body back and forth as a response. Males build bubble nests of various sizes and thicknesses at the surface of the water. Plants or rocks that break the surface often form a base for bubble nests. The act of spawning itself is called a "nuptial embrace", for the male wraps his body around the female; around 10–40 eggs are released during each embrace, until the female is exhausted of eggs. The male, in his turn, releases milt into the water, and fertilization takes place externally. During and after spawning, the male uses his mouth to retrieve sinking eggs and deposit them in the bubble nest (during mating the female sometimes assists her partner, but more often she simply devours all the eggs she manages to catch). Once the female has released all of her eggs, she is chased away from the male's territory, as she will likely eat the eggs. The eggs remain in the male's care. He carefully keeps them in his bubble nest, making sure none falls to the bottom, repairing the bubble nest as needed. Incubation lasts for 24–36 hours; newly hatched larvae remain in the nest for the next two to three days until their yolk sacs are fully absorbed. Afterwards, the fry leave the nest and the free-swimming stage begins. In this first period of their lives, B. splendens fry are totally dependent on their gills; the labyrinth organ which allows the species to breathe atmospheric oxygen typically develops at three to six weeks of age, depending on the general growth rate, which can be highly variable. B. splendens can reach sexual maturity at an age as early as 4–5 months.

 

History

The people of Siam and Malaya (now Thailand and Malaysia) are known to have collected these fish prior to the 19th century from the wild.

In the wild, bettas spar for only a few minutes or before one fish backs off. Bred specifically for fighting, domesticated betta matches can go on for much longer, with winners determined by a willingness to continue fighting. Once one fish retreats, the match is over.

Seeing the popularity of these fights, the king of Siam started licensing and collecting these fighting fish. In 1840, he gave some of his prized fish to a man who, in turn, gave them to Dr. Theodor Cantor, a medical scientist. Nine years later, Dr. Cantor wrote an article describing them under the name Macropodus pugnax. In 1909, the ichthyologist Charles Tate Regan, realizing a species was already named Macropodus pugnax, renamed the domesticated Siamese fighting fish Betta splendens.

1892 this species was imported to France, and 1896 the famous aquarium fish importer Paul Matte in Berlin, imported the first specimens to Germany from Moscow.

 

Aquarium keeping

Betta species prefer a warmer water climate than other tropical fish - around 25-30°C (77-86°). They have an organ known as the labyrinth organ which allows them to breathe air at the water's surface. This organ was thought to allow the fish to be kept in unmaintained aquaria, but this is a misconception, as poor water quality makes all tropical fish, including Betta splendens, more susceptible to diseases such as fin rot.

Properly kept and fed a correct diet, Siamese fighting fish live about two to four years in captivity, and up to 10 years in rare cases.