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.
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.
- Habitat Regions
- temperate
- freshwater
- 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.
- Other Physical Features
- bilateral symmetry
- Sexual Dimorphism
- sexes alike
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.
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.
- Mating System
- polygynandrous (promiscuous)
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.
- Key Reproductive Features
- seasonal breeding
- gonochoric/gonochoristic/dioecious (sexes separate)
- sexual
- fertilization
- broadcast (group) spawning
- oviparous
Ozark minnows do not exhibit parental care besides spawning. Females lay eggs and
males fertilize them, after which the eggs are left behind.
- Parental Investment
- female parental care
-
pre-fertilization
- provisioning
-
protecting
- female
Lifespan/Longevity
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
.
- Key Behaviors
- natatorial
- motile
- social
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.
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.
- Other Communication Modes
- vibrations
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
).
- Primary Diet
- omnivore
- 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
.
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.
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.
Additional Links
Contributors
Katy Bromeland (author), Minnesota State University, Mankato, Robert Sorensen (editor), Minnesota State University, Mankato, Catherine Kent (editor), Special Projects.
- 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.
- native range
-
the area in which the animal is naturally found, the region in which it is endemic.
- 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).
- freshwater
-
mainly lives in water that is not salty.
- 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.
- 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
- fertilization
-
union of egg and spermatozoan
- external fertilization
-
fertilization takes place outside the female's body
- oviparous
-
reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.
- female parental care
-
parental care is carried out by females
- natatorial
-
specialized for swimming
- motile
-
having the capacity to move from one place to another.
- social
-
associates with others of its species; forms social groups.
- vibrations
-
movements of a hard surface that are produced by animals as signals to others
- omnivore
-
an animal that mainly eats all kinds of things, including plants and animals
- 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.
- tactile
-
uses touch to communicate
- chemical
-
uses smells or other chemicals to communicate
References
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.
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 .