Livebearers- live bearing fish
These live bearing fish give birth to young ones which are free swimming.
Members of the family Poeciliidae are the favoured ornamental live bearing fish for the hobbyists and the most common among them are the guppies, mollies, platys and swordtails.
Halfbeaks , splitfins, and freshwater sting rays are rarer ornamental live bearing fish kept by advanced hobbyists.
Livebearers vs oviparous (egg laying) species
The egg laying ornamental species lays thousands of eggs at one time and the eggs and the hatchlings are subjected to great dangers and predation and only a few grow into adults in the nature.The ornamental livebearers fish produce limited number of off-springs depending upon the size and age of the live bearing fish mother.
However their babies have the advantage of bigger size when compared to hatchlings from eggs and have better survival rate.
Breeding habit of ornamental livebearers
The female livebearers do not lay eggs like most of the oviparous ones.The eggs are retained inside the body of the live bearing fish mother and the fertilisation takes place inside the body.
After full growth the babies are released from the body by the live bearing fish. There are two types of livebearers namely ovoviviparous types and viviparous types.
Ovoviviparous live bearing fish
In ovoviviparous live bearing fish though the eggs are retained in the body, except for protection, the eggs are independent of their mother.They do not derive any nutrition from the mother. The members of the family Poeciliidae like guppies etc belong to this group.
Viviparous live bearing fish
The ornamental females have structures for supplying nutrition to the eggs which are analogous to placenta of mammals. The halfbeak and splitfins come under this group of live bearing fish.The males have intense reproductive instinct of chasing females and mating them.
The male to female ratio of live bearing fish may be kept greater than 1:3 so that the females are not stressed.
The female tend to be larger in size when compared to males livebearers.
The males of livebearers deposit the sperms in 'packs' called spermatophore into females.
With one time mating live bearing guppy female can keep producing 4-5 broods without further mating using the earlier deposit.
Temperament and social behaviour of livebearers
The ornamental live bearing fish are docile in nature and move in groups preferring company. They can also be kept in community aquarium as they are compatible with other species.The sword tails among the ornamental livebearers are very active and they may jump out of the aquarium tank. Care must be taken to properly cover the tank. The dominant males may chase away the weaker ones. These have the tendency to eat their own young ones and if they breed in the tank the young ones must be transferred to another tank to save them from being eaten up.
Care of ornamental livebearers
These live bearing fish do well in higher hardness of water. Mollies and guppies prefer slight salinity for healthy growth. Swordtails and platys do well in cold waters and do not require heating. These ornamental live bearing fish are omnivorous and accept formula feed readily.Ornamental Guppy livebearers (Poecilia reticulata): These ornamental livebearers are very hardy ones suitable for beginners.The females tend to be larger than males.
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