Notropis nubilusOzark minnow

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Geographic Range

Ozark minnows inhabit the Ozark and Paleozoic Plateaus in the central highlands of the United States. They are most abundant in the Ozark Plateaus of Missouri, Arkansas, Oklahoma and Kansas. As a result of agricultural activities, they are much less abundant in the upper Mississippi River basin including Minnesota, Iowa, Illinois and Wisconsin. Other populations are found in the Red Cedar River system in northern Wisconsin and the Mississippi River tributaries in southern Wisconsin, as well as the Zumbro, Root, and Cedar Rivers in southeastern Minnesota. Ozark minnows are also found in northern and central Arkansas, Missouri, and northeastern Oklahoma. (Berendzen, et al., 2010; Minnesota Department of Natural Resources, 2012; "ARKive Images of Life on Earth", 2012)

Habitat

Ozark minnows prefer clear, small- to medium-sized streams, with minimal vegetation and slow currents. They are found in protected backwaters near riffles or in pools where the current is slow with a gravel bottom. Ozark minnows school near the bottom in shallow water less than 8 in deep (30 cm), where the bottom is gravel. ("Endangered Resources Program Species Information", 2011; "mdconline Missouri Department of Conservation", 2012)

  • Aquatic Biomes
  • benthic
  • rivers and streams

Physical Description

Ozark minnows are small slender minnows with dark yellow-olive backs and upper sides and dark-edged scales. Their lower sides are silvery with a prominent dusky stripe at the midline that extends forward past the eye. The midline of the back has a dusky stripe overlaid with a series of golden spots that are visible when the fish is in the water. The mouth is positioned at the tip of the blunt snout, and Ozark minnows have prominent eyes that appear large in proportion to the head. Their total length is 2.2 inches to a maximum of about 4 inches. ("Endangered Resources Program Species Information", 2011; "mdconline Missouri Department of Conservation", 2012; Minnesota Department of Natural Resources, 2012; "ARKive Images of Life on Earth", 2012)

  • Sexual Dimorphism
  • sexes alike
  • Range length
    56 to 92 mm
    2.20 to 3.62 in

Development

Spawning in Ozark minnows has mostly been observed in water at 17 to 18 degrees Celsius at depths of 1 to 20 cm. This occurs over 0.5 to 1.0 cm gravel in a 13 m section of shoreline. Spawning can be delayed due to colder water and often will not take place until the water has reached 17 degrees Celsius. Spawning occurs in existing shallow depressions of approximately 8 to 20 cm in diameter. The most intense spawning occurred in shallow water of 1 to 2 cm deep, and occurred throughout the day. Ozark minnow eggs average at 2.1 mm in diameter. ("Endangered Resources Program Species Information", 2011; Berendzen, et al., 2010; Minnesota Department of Natural Resources, 2012; "ARKive Images of Life on Earth", 2012)

Reproduction

Ozark minnows approach the spawning site and stay there for a few seconds until 10 to 20 additional fish approach. At that time, all the fish begin vibrating against the bottom of the stream and each other. This lasts approximately one minute and then all of the fish vacate the area. (Fowler, et al., 1984)

Ozark minnows breed from May to early August, when the water temperature is 17 to 18 degrees Celsius. Breeding Ozark minnows often have a yellowish-orange coloration on the underside of the body and the fins. Males are more brightly colored than females during the breeding season, and may develop pronounced tubercles on the head and fins. Spawning lasts approximately one minute, but occurs throughout the day. Ozark minnows vibrate vigorously against the substrate and other fish in the group. Spawning occurs at depths of 1 to 20 cm in shallow depressions approximately 8 to cm in diameter over 0.5 to 1.0 cm gravel in a 13 m section of shoreline. The spawning occurred in existing shallow depressions approximately 8 to 20 cm in diameter. Ozark minnows lay their eggs in nests of the hornyhead chubs, and often hybridize with other shiners. The eggs average at 2.1 mm in diameter. Both males and females reach reproductive maturity at 2 years of age. ("Endangered Resources Program Species Information", 2011; Fowler, et al., 1984; Minnesota Department of Natural Resources, 2012; "ARKive Images of Life on Earth", 2012)

  • Breeding interval
    Ozark minnows breed in spring after water temperatures reach 17 degrees Celsius.
  • Breeding season
    Spawning occurs from May through early August.
  • Average age at sexual or reproductive maturity (female)
    2 years
  • Average age at sexual or reproductive maturity (male)
    2 years

Ozark minnows do not exhibit parental care besides spawning. Females lay eggs and males fertilize them, after which the eggs are left behind. (Fowler, et al., 1984)

Lifespan/Longevity

The lifespan of Ozark minnows is 2 to 4 years. ("mdconline Missouri Department of Conservation", 2012)

Behavior

Ozark minnows are often found in schools near stream bottoms. They live in large schools with other common minnows such as bleeding shiners, cardinal shiners and duskystripe shiners. (Berendzen, et al., 2010; Gelwick, et al., 1997)

Home Range

The home range for Ozark minnows is not known, but the estimated home ranges for similar species ranges from 3,264 to 19,525 sq m. Other species of the genus Notropis have been known to travel from one side of a lake to the other within a 24 hour period. (Valley, et al., 2010)

Communication and Perception

There is no information available regarding communication and perception in Ozark minnows. Like all fish, Ozark minnows have a lateral line system that helps them detect changes in pressure and temperature in the local environment.

Food Habits

Ozark minnows eat mainly green algae, blue-green algae and diatoms. They are omnivorous, feeding mostly on plant material with some animal matter. Diet may also include small insect larvae and crustaceans (Crustacea). ("Endangered Resources Program Species Information", 2011; "mdconline Missouri Department of Conservation", 2012; "ARKive Images of Life on Earth", 2012)

  • Animal Foods
  • mammals
  • insects
  • Plant Foods
  • algae

Predation

Predators of Ozark minnows are not specifically known. However, other congeners are preyed upon by largemouth bass. (Valley, et al., 2010)

Ecosystem Roles

Ozark minnows are both predators and prey in their ecosystems. They are not known to become infected with parasites.

Economic Importance for Humans: Positive

Ozark minnows have no known positive impacts on humans.

Economic Importance for Humans: Negative

There are no known negative economic impacts on Ozark minnows.

Conservation Status

Ozark minnows are not evaluated by the IUCN Red List and have no special status on other lists. Their conservation is a concern because they are unable to tolerate excessive turbidity and siltation. Heavy agricultural use within their range poses threats to their viability. Many populations are isolated from each other, meaning that this species is vulnerable to catastrophic events which may cause local population declines, such as natural disasters or disease. Recommended conservation measures for this species include protecting and restoring its habitat, conducting further research on its status and biology, and controlling pollution, erosion and agricultural runoff. ("Endangered Resources Program Species Information", 2011; Berendzen, et al., 2010; "ARKive Images of Life on Earth", 2012)

Other Comments

Fossils of Ozark minnows have been found in Meade County in southwestern Kansas that date back to the late Illinoian glacial stage. Also, fossil bone fragments have been found in the Ouachita Highlands. Studies and collections show that Ozark minnows have been in this region for 100 years and the species was most likely brought here by glacier movements. ("Endangered Resources Program Species Information", 2011; Berendzen, et al., 2010; "ARKive Images of Life on Earth", 2012)

Contributors

Katy Bromeland (author), Minnesota State University, Mankato, Robert Sorensen (editor), Minnesota State University, Mankato, Catherine Kent (editor), Special Projects.

Glossary

Nearctic

living in the Nearctic biogeographic province, the northern part of the New World. This includes Greenland, the Canadian Arctic islands, and all of the North American as far south as the highlands of central Mexico.

World Map

benthic

Referring to an animal that lives on or near the bottom of a body of water. Also an aquatic biome consisting of the ocean bottom below the pelagic and coastal zones. Bottom habitats in the very deepest oceans (below 9000 m) are sometimes referred to as the abyssal zone. see also oceanic vent.

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

chemical

uses smells or other chemicals to communicate

external fertilization

fertilization takes place outside the female's body

female parental care

parental care is carried out by females

fertilization

union of egg and spermatozoan

freshwater

mainly lives in water that is not salty.

motile

having the capacity to move from one place to another.

natatorial

specialized for swimming

native range

the area in which the animal is naturally found, the region in which it is endemic.

omnivore

an animal that mainly eats all kinds of things, including plants and animals

oviparous

reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.

polygynandrous

the kind of polygamy in which a female pairs with several males, each of which also pairs with several different females.

seasonal breeding

breeding is confined to a particular season

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

social

associates with others of its species; forms social groups.

tactile

uses touch to communicate

temperate

that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).

vibrations

movements of a hard surface that are produced by animals as signals to others

References

Wildscreen 2003-2012. 2012. "ARKive Images of Life on Earth" (On-line). Accessed March 13, 2012 at http://www.arkive.org/ozark-minnow/notropis-nubilus/.

2011. "Endangered Resources Program Species Information" (On-line). Accessed March 13, 2012 at http://dnr.wi.gov/org/land/er/biodiversity/index.asp?mode=info&Grp=13&SpecCode=AFCJB28680.

2012 Conservation Commission of Missouri. 2012. "mdconline Missouri Department of Conservation" (On-line). Accessed March 13, 2012 at http://mdc.mo.gov/discover-nature/field-guide/ozark-minnow.

Berendzen, P., J. Dugan, T. Gamble. 2010. Post-glacial expansion into the Paleozoic Plateau: evidence of an Ozakian refugium for the Ozark minnow Notropis nubilus (Teleostei: Cypriniformes).. Journal of Fish Biology, Volume 77: 1114-1136. Accessed February 08, 2012 at http://web.ebscohost.com/ehost/pdfviewer/pdfviewer?vid=2&hid=112&sid=780df894-6f9b-4e95-8497-1d46510e31bf%40sessionmgr115.

Fowler, J., P. James, C. Taber. 1984. Spawning Activity and Eggs of the Ozark Minnow, Notropis nubilus. Copeia, Volume 4: 994-996. Accessed February 08, 2012 at http://www.jstor.org/stable/1445348?seq=2&Search=yes&searchText=nubilus&searchText=Notropis&list=hide&searchUri=%2Faction%2FdoBasicSearch%3FQuery%3DNotropis%2Bnubilus%26acc%3Don%26wc%3Don&prevSearch=&item=3&ttl=53&returnArticleService=showFullText&resultsServiceName=null.

Gelwick, F., M. Stock, W. Matthews. 1997. Effects of fish, water depth, and predation risk on patch dynamics in a north-temperate river ecosystem. Oikos, Volume 80:2: 382-398. Accessed February 08, 2012 at http://www.jstor.org/stable/3546606.

Minnesota Department of Natural Resources, 2012. "Minnesota Department of Natural Resources" (On-line). Accessed February 08, 2012 at http://www.dnr.state.mn.us/rsg/profile.html?action=elementDetail&selectedElement=AFCJB28680.

USGS, 2009. "USGS NAS-Nonindigenous Aquatic Species" (On-line). Accessed February 08, 2012 at http://nas.er.usgs.gov/queries/FactSheet.aspx?speciesID=603.

Valley, R., M. Habrat, E. Dibble, M. Drake. 2010. Movement patterns and habitat use of three declining littoral fish species in a north-temperate mesotrophic lake. Hydrobiologia, 644: 385-399.