Betta /ˈbɛtə/ is a large genus of small, often
colorful, freshwater
ray-finned
fishes in the gourami
family (Osphronemidae). The type
species is B. picta, the spotted
betta.[1]
By far the best known Betta species, however, is B. splenndes,
the Siamese fighting fish.
Characteristics
Bettas are anabantoids, which means they can breathe atmospheric air using a unique organ called the labyrinth. This accounts for their ability to thrive in low-oxygen water conditions that would kill most other fish, such as rice paddies, slow-moving streams, drainage ditches, and large puddles.[2]
The various bettas can be divided into two groups, based on their spawning behaviour: some build bubble nests, such as B. splendens, while others are mouthbrooders, such as B. picta. The mouthbrooding species are sometimes called "pseudo bettas", and are sometimes speculated to have evolved from the nest-builders in an adaptation to their fast-moving stream habitats.[3]
In the wild, the fish uses its coloration to ward off predators and to attract mates. Wild Bettas do not possess the vibrant bright red, lime green, and royal blue colors of their selectively bred counterparts. In fact, they are unusually dull and drab. However, captive-bred Betta males have adopted these new colors and use them to their advantage in mating displays.
The actual colors of a Betta are layered. In order to produce a Betta of specific color, other colors that are layered on top must first be "stripped away" through selective breeding. The top color is blue; next is red, then black and finally yellow.
Bettas have mouths that are upturned, indicating that they are a top feeder and will scoop up their food on the water's surface. Their fins are used not only for propulsion through the water, but for maintaining balance and turning in different directions. They have one caudal fin, one dorsal fin, two pelvic fins, one anal fin, and two pectoral fins. (Hargrove 1999)
Habitat
There are many betta species and most of them are native to South East Asia. However, Betta Splendens, which are native to Thailand, are most common for aquarium trade
Behavior
During the dry season, most Bettas are able to bury themselves in the bottom of their dried up habitat. There, they can live in moist cavities until water once again fills the depression during a rainy period. The fish can survive even if thick, clay mud is all that is left of the water. They do not survive total drying out of the bottom. (Vierke 1988)A well-known behavioral characteristic of the Betta is fighting. Male Bettas, more commonly than females, instictively fight with one another to defend their territory. In the Orient, the fish's animosity towards its own kind is capitalized upon through the medium of staged fights. Fighting fish have been bred for competitive fighting for centuries. Considerable sums of money are exchanged in wagers on these fights, which are illegal in the United States. (Ostrow 1989) Wild fighting fish rarely keep up their fights for more than 15 minutes, unlike the cultivated varieties which are considered poor if they fight for less than an hour. (Rodgers 1990)
In reproduction, the Bettas have their own choreographed dance. When the female is finally ready to spawn, she approaches the male under the nest, swimming towards him in an oblique, head-down position with her fins closed against her body. This approach seems to signal the male that she is ready to mate, and he approachs her more gently than his previously aggressive displays. Before the first spawning embrace begins, there may be a few more mutal displays under the nest, during which time the colors of both fish become very intense. With fins spread and colors flashing, the pair begins to "dance". (Ostrow 1989) The fish circle one another, nudging each other in the sides with their snouts. The courtship ends with the male turning the female on her side and wrapping himself around her. He then tightens his grip, turns her upside down, and, in a short while, lets her go. As she remains suspended in the upside-down position, he stations himself beneath her. The female begins to lay 3-7 eggs at a time, to a total of several hundred eggs. As these slowly sink, the male catches the whitish eggs in his mouth. He then coats the eggs with mucus, swims up to his nest, and blows them into the mass of bubbles. While the male Betta is doing this, the female recovers from the embrace. This procedure is repeated until all the eggs are laid, with the male looping himself round the female each time to fertilize the eggs as she lays them. Finally, the male drives the female away. (Rodgers 1990)
Food Habits
Wild Betta splendens feed mainly on insects that have fallen into the water. Because of their rapid metabolic rate, Bettas need to eat frequent, small "snacks", such as algae, to hold them over until their next big meal. (Hargrove 1999) Five different feeding methods have been observed in the Betta: snapping, scooping/gulping, grazing, jumping, and spitting. Snapping is the method most commonly used to "capture" their morsels of food. (Vierke 1988)
Reproduction
Mating begins with the male Betta building a nest of bubbles. To build this nest, the male swims to the surface, takes a gulp of air and spits out a mucus-coated air bubble. He then quickly takes another bubble of air and releases it near the first one. This process continues for hours with occasional breaks for food or to court the female. After awhile, the nest begins to take on a definate shape. However, the shape and size varies.Once the nest is nearly complete, an extremely intense and often rough courtship begins. The male very aggressively pursues the female, attempting to entice her under the nest. In his efforts to bring her to the nest, he can be quite brutal if she doesn't willingly respond. More often than not, by the time the first spawning embrace begins, the female's fins are badly torn and she may even be missing some scales.
After spawning has occured, the male then guards the nest, taking care of the eggs until the young hatch 24 to 48 hours later, depending upon the temperature of the water. The young Bettas don't begin to show very much color or fin shape until they are about three months old. At about this time, males begin to fight with one another. It is also quite easy to sex Bettas around this age, as the males are usually more brightly colored and have longer fins than the females. The fish reaches sexual maturity around five months. (Ostrow 1989)
References
Hargrove, M. 1999. The Betta: an Owner's Guide to a Happy Healthy Fish. New York: Howell Book House.Ostrow, M. 1989. Bettas. New Jersey: T.F.H. Publications, Inc..
Rodgers, N. 1990. The Marshall Cavendish Wildlife Encyclopedia. New York: Marshall Cavendish Corp..
Vierke, J. 1988. Bettas, Gouramis, and Other Anabantoids. New Jersey: T.F.H. Publication, Inc..
http://en.wikipedia.org/wiki/Betta
to be continues ...
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