Topeka Shiner

Notropis topeka

Description

The Notropis topeka (Topeka shiner) is a small, stout minnow, not exceeding 3 in (8 cm) in length. The head is short with a small, moderately oblique (slanted or sloping) mouth. The eye diameter is equal to or slightly longer than the snout. The dorsal (back) fin is large, with the height more than one half the predorsal length of the fish, originating over the leading edge of the pectoral (chest) fins. Dorsal and pelvic fins each contain eight rays (boney spines supporting the membrane of a fin). The anal and pectoral fins contain seven and 13 rays respectively, and there are 32-37 lateral line scales. Dorsally the body is olivaceous (olive-green), with a distinct dark stripe preceding the dorsal fin. A dusky stripe is exhibited along the entire longitudinal length of the lateral line. The scales above this line are darkly outlined with pigment, appearing cross-hatched. Below the lateral line the body lacks pigment, appearing silvery-white. A distinct chevron-like spot exists at the base of the caudal (tail) fin.

Behavior

The Topeka shiner swims independent of currents and is an insectivore (insect eater). It is primarily a diurnal (daytime) feeder on insects, with midges, true flies, and mayflies, making up the bulk of the diet. However, zooplanktons also contribute significantly to the species' diet. The Topeka shiner is reported to spawn in pool habitats, over green sunfish and orange spotted sunfish nests, from late May through July in Missouri and Kansas. Males are reported to establish small territories near these nests. The Topeka shiner is an obligate (essential) spawner on silt-free sunfish nests, but it is unlikely that the species is solely reproductively dependent on sunfish; the shiner also utilizes other silt-free substrates as spawning sites. Maximum lifespan for the Topeka shiner is three years; however, only a very small percentage lives to the third summer.

Habitat

The Topeka shiner occupies small, headwater, prairie streams with good water quality and cool temperatures. These streams generally exhibit year round flow, but some have periodic flow during summer. At times when surface flow ceases, pool levels and cool water temperatures are maintained by seepage through the streambed, spring flow and/or groundwater seepage. The predominant substrates within these streams are clean gravel, cobble and sand. However, bedrock and clay hard-pan (layer of hard soil) overlain by a thin layer of silt are not uncommon. Topeka shiners most often occur in pool and run areas of streams, seldom being found in choppy water. They are pelagic (living in open water) in nature, occurring in mid-water and surface areas, and are primarily considered a schooling fish. Occasionally, individuals of this species have been found in larger streams, downstream of known populations, presumably as strays.

Distribution

The Topeka shiner is a small fish presently known from small tributary streams in the Kansas and Cottonwood River basins in Kansas; the Missouri, Grand, Lamine, Chariton, and Des Moines River basins in Missouri; the North Raccoon and Rock river basins in Iowa; the James, Big Sioux and Vermillion River watersheds in South Dakota; and, the Rock and Big Sioux River watersheds in Minnesota.

Historically, the Topeka shiner was widespread and abundant throughout low order tributary streams of the central prairie regions, including portions of Iowa, Kansas, Minnesota, Missouri, Nebraska, and South Dakota. The number of known occurrences of Topeka shiner populations has been reduced by approximately 80%, with approximately 50% of this decline occurring within the last 25 years. The species now primarily exists as isolated and fragmented populations.

In Missouri, 42 of the 72 sites historically supporting Topeka shiners were re-surveyed in 1992; shiners were collected at eight of the 42 surveyed locales. In 1995, the remaining 30 historical sites not surveyed in 1992 and an additional 64 locales, thought to have potential to support the species, were sampled. Topeka shiners were found at six of the 30 remaining historical locations and at six of the 64 additional sites sampled. In total, recent sampling in Missouri identified Topeka shiners at 14 of 72 historic localities, and at 20 of 136 total sites sampled. In Iowa, 24 locales within four drainages were sampled in 1994 at or near sites from which the species was reported extant between 1975 and 1985. The Topeka shiner was captured at three of 24 sites, with these three captures occurring in the North Raccoon River basin. There were six collections of the species in 1994 and 1995, also from the same drainage. In Kansas, extensive stream surveys completed from 1995 through 1997 identified 10 new localities for Topeka shiners and reconfirmed the species in a historic locale where it was previously believed extirpated.

In South Dakota in 1997, surveys identified several specimens from two streams in Brookings County, South Dakota. In the James River basin, three new localities for the species were identified, and the species was reconfirmed from a historic locality. Two of the new locations were in Beadle County, where 29 and 4 individual Topeka shiners were captured. The other new location was in Hutchinson County, where one Topeka shiner was captured. The reconfirmed historic locale was in Davison County, where one Topeka shiner was captured. In Minnesota, 14 streams in the range of the Topeka shiner were surveyed between 1985 and 1995. The species was collected from five of nine streams with historic occurrences, and was not found in the five streams with no historic occurrences. These locales were in the Rock River drainage. In 1997, additional surveys were completed with the species being captured at 15 sites in eight streams, including a stream in the Big Sioux River basin.

In Nebraska, in 1989, the shiner was discovered in the upper Loup River drainage, where two specimens were collected. In 1996, a single specimen was collected from a stream in the Elkhorn River basin. These were the first collections of Topeka shiners in Nebraska since 1940.

Threats

The Topeka shiner is threatened by habitat destruction, degradation, modification, and fragmentation resulting from siltation, reduced water quality, tributary impoundment, stream channelization, and stream dewatering. The species also is impacted by introduced predaceous fishes.

Intensive land-use practices, maintainence of altered waterways, dewatering of streams, and continuing tributary impoundment and channelization represent the greatest existing threats to the Topeka shiner. Over-grazing of riparian zones (banks of a natural course of water) and the removal of riparian vegetation to increase tillable acreage greatly diminish a watershed's ability to filter sediments, organic wastes and other impurities from the stream system. Irrigation draw-down of groundwater levels affects surface and subsurface flows which can impact the species. At present, both Federal and State planning for development of watershed impoundments and channelization and/or its maintenance continue in areas with populations of Topeka shiners. Several impoundments are planned for construction on streams with abundant numbers of the species. Portions of these stream reaches will be inundated by the permanent pools of the reservoirs, imperiling the species' future existence in these localities. Prior to the planning of the impoundments, these populations of Topeka shiners were considered to be the most stable range-wide, due to their occurrence in watersheds dominated by high quality prairie with generally very good grazing management and land stewardship.

Conservation and Recovery

A number of Federal agencies have jurisdiction and responsibilities potentially affecting the Topeka shiner. Federal involvement is expected to include the Corps of Engineers throughout the species' range with respect to its administration of the Clean Water Act. The U.S. Environmental Protection Agency will need to consider the Topeka shiner in the registration of pesticides, adoption of water quality criteria, and other pollution control programs. The U.S. Department of Transportation, Federal Highway Administration, will need to consider the effects of bridge and road construction at locations where known habitat may be impacted. The U.S. Department of Agriculture, Natural Resources Conservation Service and Farm Service Agency, will need to consider the effects of structures and channelization projects installed under the Watershed Protection and Flood Prevention Act, the Farm Bill programs, and other activities which may impact water quality, quantity, or timing of flows. The Federal Energy Regulatory Commission will need to consider potential impacts to the Topeka shiner and its habitat resulting from gas pipeline construction over streams and from hydroelectric development.

Contacts

U. S. Fish and Wildlife Service
Kansas Ecological Services Field Office
315 Houston Street, Suite E
Manhattan, Kansas 66502-6172
Telephone: (913) 539-3474
Fax: (913) 539-8567

U. S. Fish and Wildlife Service
Regional Office, Division of Endangered Species
1 Federal Drive
BHW Federal Building
Fort Snelling, Minnesota 55111
Telephone: (612) 713-5360
http://midwest.fws.gov/

U. S. Fish and Wildlife Service
Regional Office, Division of Endangered Species
P.O. Box 25486
Denver Federal Center
Denver, Colorado 80225
http://www.r6.fws.gov/

References

U. S. Fish and Wildlife Service. 15 December 1998. "Final Rule To List the Topeka Shiner as Endangered." Federal Register 63(240):69008-69021.