The Nonindigenous Occurrences section of the NAS species profiles has a new structure. The section is now dynamically updated from the NAS database to ensure that it contains the most current and accurate information. Occurrences are summarized in Table 1, alphabetically by state, with years of earliest and most recent observations, and the tally and names of drainages where the species was observed. The table contains hyperlinks to collections tables of specimens based on the states, years, and drainages selected. References to specimens that were not obtained through sighting reports and personal communications are found through the hyperlink in the Table 1 caption or through the individual specimens linked in the collections tables.

Etheostoma blennioides
Etheostoma blennioides
(Greenside Darter)
Native Transplant

Copyright Info
Etheostoma blennioides Rafinesque, 1819

Common name: Greenside Darter

Taxonomy: available through www.itis.govITIS logo

Identification: Page and Burr (1991); Etnier and Starnes (1993); Jenkins and Burkhead (1994); Pflieger (1997).

Size: Up to 17 cm TL. Commonly 6-8 cm TL.

Native Range: Great Lakes and Mississippi River basins from New York and Maryland to eastern Kansas and Oklahoma, and from Ontario south to Georgia, Alabama, and Arkansas; Atlantic Slope in Mohawk drainage, New York (Page and Burr 1991).

Native range data for this species provided in part by NatureServe NS logo
Hydrologic Unit Codes (HUCs) Explained
Interactive maps: Point Distribution Maps

Nonindigenous Occurrences: The Greenside Darter is probably introduced in the Potomac drainage in Maryland and Virginia (Jenkins and Burkhead 1994; Starnes et al. 2011). It was not collected in this drainage until 1954 when the first specimens were taken in Maryland. The first collections from the Virginia portion of the drainage were in 1964. Its recent appearance combined with its rapid range expansion suggest an introduction. This species is now established in creeks in Frederick County and the Potomac drainage in Loudon County, Virginia and the Chesapeake and Ohio Canal National Historical Park, Maryland (Jenkins and Burkhead 1994; Starnes et al. 2011). It was first collected from the upper portion of the Susquehanna drainage in Pennsylvania in 1962 (Denoncourt et al 1977), in the New York portion in 1998 (Carlon and Daniels 2004; Neely and George 2006), and from the Maryland portion of the drainage in 2002 (Neely and George 2006).

Table 1. States with nonindigenous occurrences, the earliest and latest observations in each state, and the tally and names of HUCs with observations†. Names and dates are hyperlinked to their relevant specimen records. The list of references for all nonindigenous occurrences of Etheostoma blennioides are found here.

StateFirst ObservedLast ObservedTotal HUCs with observations†HUCs with observations†
MD195720236Cacapon-Town; Conococheague-Opequon; Lower Susquehanna; Middle Potomac-Catoctin; Monocacy; North Branch Potomac
NY199820123Chemung; Owego-Wappasening; Upper Susquehanna
PA1962202421Bald Eagle; Cacapon-Town; Chemung; Conococheague-Opequon; Lower Juniata; Lower Susquehanna; Lower Susquehanna-Penns; Lower Susquehanna-Swatara; Lower West Branch Susquehanna; Middle West Branch Susquehanna; Monocacy; North Branch Potomac; Owego-Wappasening; Pine; Raystown; Sinnemahoning; Tioga; Upper Juniata; Upper Susquehanna-Lackawanna; Upper Susquehanna-Tunkhannock; Upper West Branch Susquehanna
VA194520236Conococheague-Opequon; Middle New; Middle Potomac-Catoctin; North Fork Shenandoah; Potomac; South Fork Shenandoah
WV196320044Cacapon-Town; Conococheague-Opequon; Shenandoah; South Branch Potomac

Table last updated 6/16/2024

† Populations may not be currently present.

Ecology: Greenside Darters inhabit riffles and vegetated areas of small to medium rivers; occassionally along shorelines of large lakes (Cooper 1983; Page and Burr 1991). Feeds on aquatic crustaceans and insect larvae throughout its lifecycle (Cooper 1983; Jenkins and Burkhead 1994). Spawning occurs in spring and early summer (February to June) in water temperatures of 11-23°C. Males will guard a small territory, and eggs are deposited under rocks or at the base of aquatic vegetation. No other parental care is given (Cooper 1983; Jenkins and Burkhead 1994). Maturity is generally reached by age 1-2, and the average lifespan is 3-4 years (maximum reported age of 5 years) (Cooper 1983; Jenkins and Burkhead 1994).

Means of Introduction: The origin of introduced populations in the Susquehanna and Potomac River drainages has been widely debated. Schwartz (1965) suggested that E. blennioides entered the Potomac drainage through crossovers events near the headwaters of the Potomac in West Virginia, and Stauffer et al. (1995) list it as native for the drainage. Denoncourt et al. (1977) suggest that stream capture from the Allegheny River drainage is the source of the population in the Susquehanna River drainage, and that it has been present since relatively recent geological times but not previously sampled due to lack of sampling effort in the region. Cooper (1983) regards the species as native to Pennsylvania and classifies it as a recent immigrant. Jenkins and Burkhead (1994), Neely and George (2006), and Starnes et al. (2011) argue that the lack of collection data (despite widespread sampling in these regions) prior to first reports and rapid spread throughout the watersheds is indicative of recent introduction and expansion.  Neely and George (2006) speculated bait-bucket transfer of individuals was responsible for the introduction.

Status: Established in Maryland, New York, Pennsylvania and Virginia.

Impact of Introduction: Unknown. Neely and George (2006) suggest that Greenside Darters could impact the critically endangered Maryland darter (E. sellare) in the lower Susquehanna drainage due to overlap in preferred habitats and diet.

Remarks: Several subspecies of Greenside Darter have been recognized (Miller 1968), although the current composition is in flux: a former subspecies has been elevated to species status (E. gutselli), and several authors have commented on the systematic confusion within the species (Piller et al. 2008; Stepien and Haponski 2010). Populations of Greenside Darters in the Potomac and Susquehanna drainages are the subspecies E. b. blennioides (Schwartz 1965; Stepien and Haponski 2010).

Greenside Darters are also introduced and expanding in the Green and Maitland Rivers, Ontario, Canada (Beneteau et al. 2012).

References: (click for full references)

Beneteau, C.L., R.P. Walter, N.E. Mandrak, and D.D. Heath. 2012. Range expansion by invasion: genetic characterization of invasion of the greenside darter (Etheostoma blennioides) at the northern edge of its distribution. Biological Invasions 14:191-201.

Carlson, D.M. and R.A. Daniels. 2004. Status of fishes in New York: increases, declines and homogenization of watersheds. American Midland Naturalist 152(1):104-139.

Cooper, E.L. 1983. Fishes of Pennsylvania and the northeastern United States. Pennsylvania State University Press, University Park, PA.

Denoncourt, R.F., W.A. Potter, and J.R. Stauffer, Jr. 1977. Records of the greenside darter, Etheostoma blennioides from the Susquehanna River drainage in Pennsylvania. Ohio Journal of Science 77(1):38-42.

Etnier, D.A., and W.C. Starnes. 1993. The fishes of Tennessee. University of Tennessee Press, Knowxville, TN.

Jenkins, R.E., and N.M. Burkhead. 1994. Freshwater fishes of Virginia. American Fisheries Society, Bethesda, MD.

Miller, R.V. 1968. A systematic study of the greenside darter, Etheostoma blennioides Rafinesque (Pisces: Percidae). Copeia 1968:1-40.

Neely, D.A., and A.L. George. 2006. Range extensions and rapid dispersal of Etheostoma blennioides (Teleostei: Percidae) in the Susquehanna River drainage. Northeastern Naturalist 13(3):391-402.

Page, L.M., and B.M. Burr. 1991. A field guide to the freshwater fishes of North America north of Mexico. The Peterson Guide Series, vol. 42. Houghton Mifflin Company, Boston, MA.

Piller, K.R., H.L. Bart, and D.L. Hurley. 2008. Phylogeography of the greenside darter complex, Etheostoma blennioides (Teleostomi: Percidae): a wide-ranging polytypic taxon. Molecular Phylogenetics and Evolution 46:974-985.

Pflieger, W. 1997. The fishes of Missouri. Missouri Department of Environmental Conservation, Jefferson City, MO.

Schwartz, F.J. 1965. The distribution and probable postglacial dispersal of the percid fish, Etheostoma b. blennioides, in the Potomac River. Copeia 1965(3):285-290.

Starnes, W.C., J. Odenkirk, and M.J. Ashton. 2011. Update and analysis of fish occurrences in the lower Potomac River drainage in the vicinity of Plummers Island, Maryland—Contribution XXXI to the natural history of Plummers Island, Maryland. Proceedings of the Biological Society of Washington 124(4):280-309.

Stauffer, J.A., Jr., J.M. Boltz, and L.R. White. 1995. The fishes of West Virginia. Proceedings of the Academy of Natural Sciences of Philadelphia 146:1-389.

Stepien, C.A., and A.E. Haponski. 2010. Systematics of the greenside darter Etheostoma blennioides complex: consensus from nuclear and mitochondrial DNA sequences. Molecular Phylogenetics and Evolution 57(1):434-447.

Tilmant, J.T. 1999. Management of nonindigenous aquatic fish in the U.S. National Park System. National Park Service. 50 pp.

Other Resources:
Ohio A to Z species guide (Ohio Department of Natural Resources)

Animal Diversity Web (University of Michigan Museum of Zoology)

FishBase Summary

Author: Matt Neilson, and Pam Fuller

Revision Date: 4/30/2018

Peer Review Date: 5/16/2012

Citation Information:
Matt Neilson, and Pam Fuller, 2024, Etheostoma blennioides Rafinesque, 1819: U.S. Geological Survey, Nonindigenous Aquatic Species Database, Gainesville, FL, https://nas.er.usgs.gov/queries/FactSheet.aspx?SpeciesID=808, Revision Date: 4/30/2018, Peer Review Date: 5/16/2012, Access Date: 6/16/2024

This information is preliminary or provisional and is subject to revision. It is being provided to meet the need for timely best science. The information has not received final approval by the U.S. Geological Survey (USGS) and is provided on the condition that neither the USGS nor the U.S. Government shall be held liable for any damages resulting from the authorized or unauthorized use of the information.


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Citation information: U.S. Geological Survey. [2024]. Nonindigenous Aquatic Species Database. Gainesville, Florida. Accessed [6/16/2024].

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