Mosquitofish
Gambusia holbrooki & Gambusia affinis

Due to their name, the Mosquitofish, also known as Gambusia, may sound like some sort of unpleasant creature, but in fact, they are quite the opposite. These fish play a big role in the ecosystem because they help control the population of mosquitoes, as well as other little insects. Mosquitofish are pale gray with pronounced abdomens that are either white or dirty white. They are also sexually dimorphic, meaning there are obvious differences between males and females. They are relatively small compared to other fish with the females measuring up to seven centimeters, and the males around four centimeters. Males are also thinner than the females.

The Mosquitofish’s diet consists of zooplankton and insects. This means that they are larvivorous fish. Mosquitofish will eat mosquitoes in all stages of life. Females have a voracious appetite and are able to eat hundreds of mosquito larvae in a day! It is also known that some Mosquitofish can be cannibalistic.

For the majority of their life, these fish will be living in standing water. This is where mosquitoes lay their eggs. In these waters, Mosquitofish will lay 40-100 fry (young fish) on average, with the gestation period lasting 16-28 days.  They will have about 3-4 broods each year. The average lifespan for mosquitofish are 2 years.

Mosquitofish can be found anywhere from the Mississippi River to northeastern parts of Mexico. They are considered the most widespread freshwater fish because they can live in inhospitable environments. For example, they can live in water that has twice the salt concentration than the ocean. They can also handle water temperature up to 108°F for short periods of time. They are also considered the most widespread freshwater fish because of many countries using them as a natural biocontrol for mosquitoes.

Although Mosquitofish are considered one of the best forms of mosquito control, they can actually cause damage to the environment if not handled properly. When Mosquitofish consume large amounts of mosquito larvae, it creates competition for other fish that also eat mosquitoes. The Mosquitofish comes out on top because they can out-compete their competitors. Mosquitofish are also known to be aggressive and attack other small fish.  This can create a negative impact on small fish populations. Nevertheless, a lot of people consider the benefit of killing mosquitoes is greater than the damage the Mosquitofish can cause. For example, these fish have eradicated malaria in several places such as Russia, South America, and the Ukraine.

Mosquitofish certainly play a vital role to the ecosystem if used properly. They prove most useful if introduced to wetlands, like Green Cay which is a waste-water wetland, and farm ponds. Green Cay offers a night program called The Night Stalkers which allows guests to view nocturnal animals without worrying about mosquitoes. It is held once a month and is $5 per person. To take part in this tour, make sure to call (561) 966-7000.Without these creatures, we would be overrun by pests like mosquitoes.

By Arisa Taylor