Mosquitoes are a huge nuisance to us, but what natural predators exist to keep their numbers under control? Many scientists have studied mosquitoes and their natural predators in the wild in order to find a species that could be introduced to reduce our growing mosquito population. They have found that bats and birds kill adult mosquitoes in very high numbers. However, they are the least effective predator as they stray to other prey when mosquito populations begin to decrease. Unfortunately, mosquitoes make up only a small portion of their diet. Fish and other insects feed on the mosquito larvae.
The Gambusia affinis, also known as the mosquito fish, aggressively eat mosquito larvae and have been used since the early twentieth century for mosquito control. This method of control can be detrimental, however, because the mosquito fish also eat the eggs, larvae, and young of other native fish and amphibians in their environment. Mosquito fish are effective in controlling mosquito larvae populations in controlled situations such as drainage ditches and ornamental ponds. Dragonflies are also a natural predator of mosquitoes, feeding on them at all stages. Dragonfly larvae eat mosquito larvae while adult dragonflies eat adult mosquitoes. Dragonflies also eat other prey and are not effective in eliminating a mosquito population in any given area. One of the most effective natural predators of mosquitoes is a bacteria called Bacillus thuringiensis israelensis or BTI. BTI targets mosquito larvae without harming people or other species. The combination of bats, birds, dragonflies, and BTI is perhaps the most effective, natural control method!