Description

The mosquitofish is a small gray fish with a short body, upturned mouth, and a flattened head. The dorsal fin is located well back toward the tail with the front of the fin starting behind the front of the anal fin. The mouth is upturned and there are no bars or bands on the sides. They have small dark spots on their fins and occasionally their back or sides.

Habitat and Habits

They prefer ponds or very slow flowing streams with clear water and abundant aquatic vegetation. Mosquitofish are found in much of the southern U.S. and are often introduced as a biological control for mosquito larvae. As a result they can be found sporadically throughout Ohio.

Reproduction and Care of the Young

The mosquitofish can spawn from May through September with females carrying an average of 40 young. This species is one of the few freshwater fish species that bears live young. Because the young are born live they are already able to swim around and feed much like the adults. These fish can increase their population very rapidly. Mosquitofish become sexually mature when they reach one to one and a half inches in length, and most do not live more than two years.

Quick Facts

• Fish Family: Poeciliidae (Livebearers)


• Other Names: None


• Ohio River: Introduced


• Adult Size: Females 2-3 inches, males 1-1.5 inches.


• Typical Foods: Mosquito larvae and other small aquatic insect larvae.