Least darter
Etheostoma microperca Jordan & Gilbert, 1888

member of the Perch Family (Percidae)

Bakkens Pond, Sauk County, Wisconsin 9 April 1992

Habitat: Otter Creek, Mower County, Minnesota Fall 1998












What's In a Name?
Least darter: darters "dart" from place to place; this is one of the smallest species

Etheostoma (ee-thee-os´-toe-mah) taken from etheo, which means "to filter" and from stoma, which means "mouth" in Greek
microperca (micro-purr´-kah) means "small perch" in Greek


    Where Do They Live?
Least darters occur in 14 streams and 45 lakes scattered across the southern two-thirds of Minnesota. Most of the known populations occur in the Otter Tail and Upper Mississippi river systems. Least darters prefer shallow (less than 1.5 meters), clear waters with little current. They usually live in or near weedy areas over bottoms made up of gravel, sand, and silt. Least darters often share this habitat with creek chubs, northern redbelly dace, tadpole madtoms, and Johnny darters.


How Big Do They Get?
How Long Do They Live?
The least darter is one of the smallest darters in Northern America and is Minnesota's smallest fish. This species rarely get bigger than 38 mm (1.5 in) in length and 0.5 g (less than 0.02 oz). The differences are small, but females ultimately grow larger than males. Not only are least darters small, they have a short lifespan of usually 2 years. Less than 2 % of Minnesota least darters live for 3 years.

    What Do They Eat?
Least darters eat small food items that include a variety of copepods, waterfleas, midge larvae, and mayfly larvae. One least darter we examined had a minnow larva in its stomach!

What Eats Them?
Because least darters live in areas where the vegetation is very thick, they probably miss out on being lunch a lot of the time. Two known predators in lakes are largemouth bass and black crappies.


How Do They Reproduce?
Both male and female least darters are able to reproduce the next spring after they hatch. The spawning season in Minnesota is late May through most of July. They spawn on aquatic weeds that occur at the edges of pools and slow runs in streams or in the quiet shallows of lakes. Males arrive at the spawning areas before females and establish territories around a plant or sometimes a rock. When a female enters a territory the male moves quickly to her, chasing other males who are in pursuit. When the female finds a good leaf, she swims to it with her head pointing up and her tail down (she is vertical in the water). The male holds on to her back with his pectoral fins. The female releases her eggs while the male fertilizes them. Fertilized eggs stick to the plant. When the female finishes laying her eggs, she darts away to spawn with another male. The female will lay one to three eggs for each spawning act and a total of 30 or so a day. We know that on average a female produces about 180 eggs in a clutch (a clutch is a group of eggs that become ready for spawning at about the same time). But we do not know how many clutches a female can produce in a spawning season. So, we are not sure how many total eggs a female lays. There is no parental care of the eggs or the young after they hatch.


Conservation and Management
The least darter is a species of special concern because of its unusual distribution pattern. Recent studies have shown that it is more common than we once thought. These fish make excellent aquarium fish, but as do many fish from the wild they need a special permit to be collected and kept.




Permission is granted for the non-commercial educational or scientific use of the text and images on this Web document. Please credit the author or authors listed below.

Photographs by Konrad P. Schmidt
Text by Nicole Paulson & Jay T. Hatch in cooperation with
the Minnesota Department of Natural Resources' MinnAqua Aquatic Program

This page developed with funds from the
MinnAqua Program
(Minnesota Department of Natural Resources, Division of Fisheries)
and the
Sport Fish Restoration Program (Fish and Wildlife Service, US Department of the Interior)

Maintained by Jay T. Hatch
General College and James Ford Bell Museum of Natural History
University of Minnesota, Minneapolis/St. Paul

Last updated 1 March 2002