|Scientific Name:||Percina nasuta|
|Species Authority:||(Bailey, 1941)|
Hadropterus nasutus Bailey, 1941
|Red List Category & Criteria:||Least Concern ver 3.1|
|Reviewer(s):||Smith, K. & Darwall, W.R.T.|
|Facilitator/Compiler(s):||Hammerson, G.A. & Ormes, M.|
Listed as Least Concern in view of the fairly large extent of occurrence (much greater than 20,000 km2), occurrence in more than 10 locations, and lack of major threats in most of the range. However, the species is apparently rare or uncommon in most areas, declines have occurred over the long term, and some populations may be threatened by human activities, so it warrants continued conservation attention.
|Range Description:||This darter is distributed sporadically in the St. Francis, White, Arkansas, and Ouachita river drainages in the Ozark and Ouachita uplands of southern Missouri, northern Arkansas, and eastern Oklahoma (Page and Burr 2011). Recently identified distribution in Arkansas, includes Lee Creek, Frog Bayou (=Clear Creek), Mulberry River, upper White River, War Eagle Creek, Big Piney Creek, Illinois Bayou Drainage, Ouachita River, Caddo River, and South Fourche la Fare River (Robison 1992a and 1992b). Longnose Darters have not been collected in the White River in Missouri since the mid-1950s (Pflieger 1997).|
|Range Map:||Click here to open the map viewer and explore range.|
As of the early 1990s, Longnose Darters occurred in 13 different streams, in three major river systems (see Stewart 1993).
These darters are never abundant at any locality, small local populations occur throughout range (Robison and Buchanan 1988; Robison 1992a, 1992b; Wagner et al. 1984, 1985). This is one of Oklahoma's rarest species (Miller and Robison 2004). It is "fairly rare" in Arkansas (Robison and Buchanan 1988).
Buchanan (1984) noted that numbers were drastically reduced and a number of populations extirpated over the past 22 years. Populations have declined in areas where reservoirs have been constructed (Wagner et al. 1984, 1985).
Stable in Arkansas; from 1991–1992 collected from all but one (Little Missouri River) previously occupied river systems in Arkansas (C. Osborne pers comm. 1997; Robison 1992a, 1992b); believed still extant in Little Missouri River, Arkansas; population sizes are small (Robison 1992a).
Extirpated from Poteau River system, Oklahoma (Robison 1992b). Extant in Lee Creek and Little Lee Creek in Oklahoma (Oklahoma Department of Wildlife Conservation).
The few populations known in Missouri (St. Francis River, Poteau River, White River) may be extirpated, according to Stewart (1993). However, Pflieger (1997) stated that the Longnose Darter probably still exists in the St. Francis River (upstream from Lake Wappapello ) but is extremely rare.
Robison's 1991–1992 survey relocated this species at all historical locations except the St. Francis and Poteau rivers; known range was expanded and increased numbers were taken at most sites; suspected decline and historical rarity probably reflect difficulty of collection with seining techniques normally used, electrofishing used with great success.
Trend over the past 10 years or three generations is uncertain but probably has been relatively stable or slowly declining.
|Habitat and Ecology:||Habitat includes clear, small to medium rivers; gravel and rubble riffles in spring, slower quieter waters over sand and silt in fall. Also reported from an impoundment.|
Historical declines were due to habitat modification resulting from reservoir construction (Buchanan 1984; Wagner et al. 1984; Robison and Buchanan 1988; Robison 1992a, 1992b; Stewart 1993). Known threats include impoundment, drought, pollution, and altered temperature and flow regimes downstream from impoundments (Robison 1992a and 1992b, Wagner et al. 1984). Spraying of pesticides may also have a negative effect on survival (see Wagner et al. 1984). Water quality changes caused by agricultural runoff, municipal and industrial discharges, and physical alterations may have caused declines, but reservoir construction has been the major cause of extermination of many populations (Buchanan 1984). Other detrimental impacts include gravel and sand mining, channel modification for flood control, sedimentation, and water quality degradation from point and non-point sources (see Stewart 1993).
Despite these factors, as of the early 1990s, there was little or no evidence to suggest that the species was threatened (Stewart 1993). The species occurred in 13 different streams, in three major river systems; beyond the proposed second phase of reservoir construction on Lee Creek, there were few identifiable threats (see Stewart 1993). Nevertheless, the species was categorized as "threatened" by Warren et al. (2000) and Jelks et al. (2008).
|Conservation Actions:||More information is needed about reproductive biology. Conduct intensive electrofishing in St. Francis, Poteau, and White rivers to assess current status. Survey known localities to determine precise populations and abundance; search for additional populations on edge of range. Monitor known populations to continually assess trends.|
|Citation:||NatureServe 2014. Percina nasuta. The IUCN Red List of Threatened Species. Version 2015.2. <www.iucnredlist.org>. Downloaded on 05 July 2015.|