Mosquitofish or Gambusia affinis is a tiny silver-colored fish. It is a freshwater species belonging to family Poeciliidae and order Cyprinodontiformes. The name is derived from a Cuban Spanish term gambusino which means useless. Even though its name means useless, this tiny fish has proved its utility. During 1930s, this species was released in a pond of the Auckland Botanical Gardens. Later on, it was also introduced in Northland and Wellington. Mosquitofish Facts Visual Aspect Mosquitofish is a small fish with silvery sheen. Its underside is lighter in shade as compared to the whole body. A female mosquitofish measures less than 3 inches, while a male measures less than 2 inches. A female fish can be distinguished by its male counterpart on the basis of anal fin. A female anal fin is slightly round in shape whereas the male anal fin appears pointed and elongated. Mosquitofish are capable of bringing about slight change in their color in order to match the surrounding environment. Habitat This freshwater fish is native to Eastern and Southern United States, where the species flourishes in ponds and streams containing freshwater. But now, the species is widespread because of its introduction in several places as it is helpful in mosquito control. Mosquitofish can thrive in habitats with varied temperatures. On one hand, they are capable of surviving freezing temperatures while on the other hand, they can handle temperatures as high as 100ºF. Life History and Reproduction Mosquitofish can live for a year in optimum conditions. Male fish has a specialized fin for the purpose of breeding which is referred to as gonopodium. After mating, the pregnant female bears the offspring. This species does not lay eggs rather, gives birth to young ones. Hence, females do not have the responsibility of taking care of their eggs. Once the offspring are delivered, they are left alone to learn to take care of themselves. The mother fish leaves the offspring in hiding spaces before they learn to survive in open water. They mature at six weeks and breed rapidly thereafter. Diet These tiny fish feed on larvae of insects and their primary source of food is mosquito larva. Mosquitoes lay their eggs in ponds which grow into larvae and become a great source of diet for mosquitofish. They also feed on algae, thus helping in maintaining a balance in the pond's ecosystem. In case, natural resource of food is not available, a good quality flaked fish food can be used to feed them. Special Consideration As this species is very small in size, they can be easily consumed by larger fish and pond organisms. Before introducing this species in a lake or a pond, it is necessary to ensure that the water body has sufficient hideout points like rocks and aquatic plants, which can be used by them to escape from falling into prey. Mosquito Control Nowadays mosquitofish are used as a means of mosquito control, and are distributed to district residents without any charge under the mosquito control program. The species is introduced in water reservoirs, cattle ranches, private homes and any other place having standing water. The lifespan of a mosquito consists of a larval stage. As mosquito larvae develop in standing water, the presence of this fish clears the entire larval population by feeding on them, thus helping in controlling mosquitoes. Use of alternative methods like sprays and pesticides can be harmful for dragonflies and other aquatic creatures. It is therefore better to go for a natural way of control rather than using chemicals. Mosquitofish are available in pet shops, garden stores, and vector control districts. Keeping them in garden ponds, rain barrels, and aquarium does not require a legal permit. Their adaptability to a new environment is primarily because of their ability to reproduce rapidly and withstand extreme conditions of temperature, pH, and oxygen level. Hope this article has increased your awareness about facts related to mosquitofish and its usefulness to mankind.