Endemic Fishes of the New River, by Don Orth

Anyone who travels in the New River valley know it’s a very special place.  Those who study the fishes know some secrets too.   The New River is the oldest major stream in the eastern United States – it should be the Old River.  The historic Teays River originated in the Tertiary Period and at that time drained much of eastern North American in the pre-glacial period.  However, the original route of the ancient Teays was altered by glacial advances which created a massive ice dam blocking the northward-flowing Teays. Geologists maintain that the river retained its course from headwaters in the Blue Ridge province, across the Valley and Ridge province and into the Appalachian plateau for 100 million years or more.  Through this period of slow uplift of the Appalachian region the river continued to slowly erode its bedrock streambed through gaps in major mountain ranges.  This wide, shallow, bedrock river flows northward across the strike or grain of underlying geological structures (Spotila et al. 2015).

New River supports 46 native fishes, 8 of which are endemic species.  Endemic species are unique to a defined geographic location.  The endemic fishes of the New River likely diverged after geographic isolation from ancestral forms during the Pleistocene glaciation. These glaciers, as they advanced southward, displaced fishes into unfrozen tributaries.  The upper New River drainage was likely an important refugia for fishes during this most recent ice age.  This history explains why the number of native fish species in the New River is low compared with similar sized rivers in the eastern US.  However, the number of endemic species is high.    

New River near Rich Creek, Virginia.  Photo by Valerie F. Orth. 

New River has a relatively high number of endemic fishes due to two main causes: (1) the presence of natural barriers and (2) the immobility of a species.  The Pleistocene glaciers did not reach Virginia though the climatic and barrier effect was a strong influence in the New River fish fauna.  During the Pleistocene, the climate cooled and for fish in the New River, it was “no way out and no way in.”  New River fish had to stay, adapt, or die.  The mainstem falls, cascades, rapids prevented upstream dispersal after the Pleistocene glaciation.   The Pleistocene ended 10,000 years ago, leaving many native New River fishes as cool-adapted.  Few native warmwater species are widespread.   Today, the New River has the highest proportion of introduced to native fishes of any eastern USA drainage as at least 57 introduced fishes persist in the New River alongside 44 native fishes (Easton et al. 1993; Easton and Orth 1994; Angermeier and Pinder 2015; Hilling in press).     

The eight endemic fishes include three minnows, two sculpins, and three darters, all groups that typically have little or no long-range migrations. The first three endemic fishes are in cyprinids.  Cyprinids are members of the family Cyprinidae (minnows), the most species rich family of fishes in North America.  There are 53 recognized genera and 286 species of minnows in North America (Mayden 1991).

The Bigmouth Chub Nocomis platyrhynchus occurs only in the New River drainage and its distribution is allopatric with its closest relatives, the River Chub Nocomis micropogon and the Bull Chub Nocomis raneyi.  Bigmouth Chub inhabits medium- to large-sized tributaries and the mainstem New River which have a moderate gradient, warm, usually clear water, and a good mix of gravel to boulder substrates.   For more information, click here.

Bigmouth Chub male (top) and female (bottom). Photos by Hunter Hatcher (top) and D. J. Orth (bottom) 

The Kanawha Minnow Phenacobius teretulus is one of five species of Phenacobius referred to as suckermouth minnows for obvious reasons.  The Kanawha Minnow is the only Phenacobius in the New River, has a limited distribution, and is an uncommon part of the fish assemblage.  Juveniles and adults typically occur in riffles and runs of gravel, rubble, and boulder in cool to warm creeks and small to medium rivers.   For more information, click here. 

Kanawha Minnow.  Photo by Fritz Rhode.

New River Shiner Notropis scabriceps occurs in pools and slow runs of cool to warm creeks and small to medium rivers. It is more common in Blue Ridge province than in the Appalachian or Ridge and Valley provinces.  As with other New River endemics, temperature has been postulated as a major factor governing its distribution.  In one of the few temperature preferenda studies, the final thermal preference of the New River Shiner was 19.3 °C, or 66.7 °F (Shingleton et al. 1981).   Two non-native species, the telescope shiner Notropis telescopus and whitetail shiner Cyprinella galactura may also compete with the New River Shiner (Keplinger 2007).

New River Shiner.  Photo by Ben A. Cantrell.

Kanawha sculpin Cottus kanawhae was first considered a subspecies of the Banded Sculpin Cottus carolinae.  It is widely distributed in tributaries of the New River and often overlaps with the Mottled Sculpin Cottus bairdi.  Why?  I don’t know.

 

Kanawha Sculpin.  Photo by Derek Wheaton.  

 

Dorsal saddles of Kanawha Sculpin.  Photo by D.J Orth. 

Dorsal fin of Kanawha Sculpin. Photo by D.J.Orth

Bluestone sculpin Cottus sp. has a very limited distribution in the Bluestone River and little is known about its present status and distribution.   

 

Bluestone Sculpin.  Photo by Noel M. Bulkhead.  

Candy Darter Etheostoma osburni is a rare fish that’s currently under review for federal listing as an endangered species. Candy Darters are most abundant in shallow riffle and run habitats but only occurs in a limited number of streams and has declined or disappeared from some historic locations.   The proposed Mountain Valley pipeline would cross Big Stony Creek, which supports one of the remaining populations of Candy Darters.  The Candy Darter may be the most colorful local darter.  It’s occurrence in clear mountain streams means it can be seen by the avid snorkeler willing to crawl amidst the fast-flowing boulders and cobbles. Click on this video link to watch the Candy Darter behavior underwater. 

Candy Darter male.  Photo by Derek Wheaton.

Kanawha Darter Etheostoma kanawhae is a close relative of the Candy Darter and the two distributions do not overlap.  Kanawha Darter occurs in fast-flowing riffles in tributaries of the New River in North Carolina and Virginia.    Their ancestral form was likely widely distributed in the Teays and Old Mississippi rivers and separated by the Pleistocene glacial advance.  Other close relatives occur in the Ozark highlands and the upper Ohio drainage. 

Kanawha Darter male. Photo by Noel M. Burkhead. 

Appalachia Darter Percina gymnocephala is one of the rare, endemic darters of the New River.  Although it has no special state or federal status, its distribution and status has never been evaluated.    For more information,  click on this link.    Not much is known about the Appalachia Darter and its life history.  It's safe to say that as a New River endemic it's adapted for cool water and inhabits cobble and boulder habitats.  

Appalachia Darter.  Photo by Isaac Szabo. 

One cannot discuss the percid fishes of the upper New River without a mention of the Walleye Sander vitreus.  Jenkins and Burkhead (1994) considered the Walleye to be an introduced species.  However, a genetically unique walleye was discovered in the New River and is the basis for a restoration effort (Palmer et al. 2007).  Jenkins and Burkhead relied on the fact that there were no reports of Walleye by 19^th century investigators (Cope 1868 paper) and the Virginia Fish Commission.  However, no targeted investigations were ever done and intensive stocking of Walleye in Claytor Lake began after 1939.  These introductions were traceable to Lake Erie and Hudson bay stock.  Work is now underway in the Hallerman Genetics Lab at Virginia Tech to examine and continue marker-assisted selection.  The unique walleye strain is a river-spawning Walleye and may have adaptive traits that permit it to survive better in the New River.  They grow to large size (see photo). 

 

Historic state record Walleye from the New River.  22 pounds and 8 ounces.  

The endemic fishes of the New River are unique and their limited distribution means many anthropogenic activities may have a disproportionate influence on species viability.  The construction of dams on the mainstem New and its tributaries fragmented populations and eliminated coolwater habitats. In addition to hydropower dams, emerging threats include introduction of nonnative species and climate change (Angermeier and Pinder 2015).  New River is a special place for people – and now you know why its special for fishes.  

References

Angermeier, P.L., and M.J. Pinder. 2015.  Viewing the status of Virginia’s environment through the lens of freshwater fishes.  Virginia Journal of Science 66(3). Article 2 http://digitalcommons.odu.edu/vjs/vol66/iss3/2   

Cope, E.D. 1868.  On the distribution of freshwater fishes in the Allegheny region of southwestern Virginia. Journal of the Academy of Natural Science of Philadelphia, Series 2, 6, part 3, article 5 (1869):207-247.

Easton R.S. and D.J. Orth D.J. 1994. Fishes of the main channel New River, West Virginia. Virginia Journal of Science 45: 265–277.

Easton R.S., D.J. Orth, and N.M. Burkhead. 1993. The first collection of rudd, Scardinius erythrophthalmus (Cyprinidae), in the New River, West Virginia. Journal of Freshwater Ecology 8:263–264.

Hilling, C.D., S.L.Wolfe, J.R. Copeland, D.J. Orth, E. M. Hallerman. In press.  Occurrence of Two non-indigenous catostomid fishes in the New River, Virginia. Northeastern Naturalist

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

Keplinger, B.J.  An experimental study of vertical habitat use and habitat shifts in single-species and mixed-species shoals of native and nonnative congeneric cyprinids.  Masters thesis, West Virginia University, Morgantown.

Mayden, R.L. 1991.  Cyprinids of the New World.  Pages 240-263 in I.J. Winfield and J.S. Nelson, editors. Cyprinid Fishes: Systematics, Biology and exploitation.  Springer, Dordrecht

Palmer, G.C., J. Williams, M. Scott, K. Finne, N. Johnson, D. Dutton, B.R. Murphy, and E.M. Hallerman, 2007. Genetic marker-assisted restoration of the presumptive native walleye fishery in the New River, Virginia and West Virginia. Proceedings of the Annual Conference of the Southeastern Association of Fisheries and Wildlife Agencies 61:17-22.

Shingleton, M.V., C.H. Hocutt, and J.R. Stauffer, Jr. 1981.  Temperature preference of the New River Shiner.  Transactions of the American Fisheries Society 110:660-661.

Spotila, J.A., K.A. Moskey, and P.S. Prince.  2015.  Geologic controls on bedrock channel width in large, slowly-eroding catchments: Case study of the New River in eastern North America.  Geomorphology 230:51-63. 

Appalachia Darter: An Endemic Black-Blotched Darter of the New River, by Don Orth

The Appalachia Darter Percina gymnocephala is one of the rare, endemic darters of the New River.  It does not have any special state or federal status.   Darters are most derived members of the family Percidae, and their reduced or absent swimbladders and enlarged pectoral fins make them superbly adapted for benthic life. Percina is the second largest genus of the darters with 46 species.  Because members of the Percina genus are larger, with drab colors, and high meristic counts, Percina has more plesiomorphic traits than the more colorful and speciose Etheostoma (156 species).  The darters (Etheostomatinae) contains 250 species endemic to eastern North America.  

The Appalachia Darter has traditionally been classified in the subgenus Alvordius, which is the largest subgenus of Percina with 14 species.   Alvordius might be named the “black-blotched” darters in recognition of the 6 to 16 lateral black blotches that these fish all possess.  All members of this subgenus have a large terminal mouth, lateral blotches, dorsal saddles, and a broad frenum.      

F points to frenum on a darter. Illustration from Jenkins and Burkhead (1994).

The Appalachia Darter has 6-8 (sometimes 9) lateral blotches.  The blotches are may be oval, square, or rectangular, and are interconnected.  They have dorsal saddles that are sometimes interconnected to form chain-like pattern.  There is no pigmentation below the lateral band and the lateral band extends to the opercle and snout. The snout is moderately rounded and the mouth is terminal.  Appalachia Darters possess a teardrop-shaped dark spot below each eye.   Fins are mostly transparent with scattered melanophores.  There is a proximal dark band on the first dorsal fin.    

Appalachian Darter Percina gymnocephala holotype specimen from Beckham (1980)

Appalachian Darter Percina gymnocephala  photo from Jenkins and Burkhead (1994).

Early investigators recorded the presence of Appalachia Darter to be the more widespread Blackside Darter Percina maculata.   However, it was elevated to a new species after further examination of specimens by Eugene Beckham (1980).   It’s closest relatives are likely the Shield Darter Percina peltata and the Piedmont Darter Percina crassa, based on external characteristics.  In photos (below) you can observe the many similarities and differences among these darters. Much about the phylogeny of the Percina is yet to be fully explained (Near 2002; Near et al. 2011).   Several Alvordius species do not group strongly with any other Percina lineages, suggesting that presumed monophyly was inappropriate. Phylogeny is likely much more complicated that we can currently imagine.

There are many similar looking "black-blotched" darters that you may encounter; there are slight differences that may require a magnifying lens. Admittedly, the most efficient way to distinguish some of these "black-blotched" darters is to ask what drainage they are from. Many of these species do not overlap with the Appalachia Darter.   The Shield Darter Percina peltata is very similar but  has a large Atlantic slope distribution from the Hudson and Susquehanna rivers south to the James River.  The Shield Darter has rectangular or square lateral blotches that are not interconnected.

Shield Darter Percina peltata  Photo by J. Abatemarco, NJ DEP.

The Blackside Darter Percina maculata is also very similar.  It has a distinctive spot at the base of the caudal fin and possesses scales on the opercle and cheek, while the Appalachia Darter lacks all these traits. It also has a dark blotch on the front lower portion of the first dorsal fin.  Appalachia Darter has only 1-5 scales along dorsal margin of opercle.

Blackside Darter Percina maculata Photo by Uland Thomas

Piedmont darter Percina crassa is from the Cape Fear, Pee Dee, and Santee drainages and does not overlap with the Appalachia Darter.   Otherwise it is very similar and distinguishing traits are larger scales (you have to count lateral line scales).

Piedmont Darter Percina crassa   Photo Scott Smith, ncfishes.com

The Stripeback Darter Percina notogramma resembles the Appalachia Darter but is distributed in the Atlantic slope streams from the Patuxent in Maryland to the James River of Virginia.  

Stripeback Darter Percina notogramma. Photo from Jenkins and Burkhead (1994)

The Longhead Darter Percina macrocephala is another Appalachia Darter lookalike.  Note that the lateral blotches are more confluent with each other creating a lateral band pattern and the upper body lackwsdistinct saddles.  . 

Longhead Darter Percina macrocephala  Photo by Ohio DNR

The Dusky Darter Percina sciera has no teardrop under the eye.  Also, it has an irregularly shaped blotch on the caudal base that appears to be formed from three fused pigment spots. 

Dusky Darter Percina sciera Photo by Uland Thomas

The Roanoke Darter Percina roanoka is the one black-blotched darter that also occurs in the New River and may overlap some with the Appalachia Darter. The snout of the Roanoke Darter is blunter than the Appalachian Darter.  The blotches of the Roanoke Darter are more vertically elongated and there two bands of pigment (one orange, one black) in the first dorsal fin.  Roanoke Darter is the most colorful of these black-blotched darters.

Roanoke Darter, Percina roanoka. Photo by Uland Thomas

I sampled the Federally Threatened Leopard Darter Percina pantherina in southeastern Oklahoma streams many years ago (Jones et al. 1984).  It too resembles these black-blotched darters but the blotches are disconnected and the combination of blotches and saddles form "leopard" spots.  

Leopard Darter Percina pantherina  Photo by Daniel Fenner.

The Appalachia Darter are not common at the locations where they do exist.  Steven Chipps and associates (1994, while studying habitats of other darters, described habitats used by the Appalachia Darter.  Appalachia Darters were usually found in runs and shallow pools with cobble substrate.  They were observed swimming above the streambed, a trait referred to as hyperbenthic. Depths averaged 44-55cm and current velocity has 11-13 cm/s.  The associated Candy Darter Etheostoma osburni and Fantail Darter Etheostoma flabellare were in shallow and faster riffle habitats.  With such habitat affinities, the Appalachia Darter would be easy prey for large bodied sunfish, Rock Bass, and Smallmouth Bass in larger streams.   

Appalachia Darters were rarely encountered in samples from the mainstem New River in West Virginia (Easton et al. 1994) but appear to be more associated with stream reaches in the Blue Ridge province (Jenkins and Burkhead 1994).   Based on collection records summarized by Beckham (1980), the Appalachia Darter occupies cool and warm rivers with an upland gradient

Distribution of captures of Percina gymnocephala from Beckham (1980). 

Recently Jian Huang and others (2016) developed a species distribution model to predict probability of occurrence for several New River fishes.  The map below color codes the stream segments according to likelihood that the segment will support the Appalachia Darter.  However, we need to sample more segments in order to better define the factors that drive the distribution and abundance of the Appalachian Darter. 

Predicted species occurrence of Percina gymnocephala from Frimpong et al. (2014).

References

Beckham, E.C. 1983. Systematics and redescription of the blackside darter, Percina maculata (Girard), (Pisces:Percidae). Occasional Papers of the Museum of Zoology, Louisiana State University 62.

Beckham, E.C. 1980. Percina gymnocephala, a new percid fish of the subgenus Alvordius from the New River in North Carolina, Virginia and West Virginia.  Occasional Papers of the Museum of Zoology, Louisiana State University 57.

Chipps, S.R., W.B. Perry, and S.A. Perry.  1994.  Patterns of microhabitat use among four species of darters in three Appalachian streams.  The American Midland Naturalist 131:175-180.

Easton, R. S., and D. J. Orth.  1994. Fishes of the main channel New River,West Virginia. Virginia Journal of Science 45:265-277.

Frimpong, E.A., J. Huang, and Y. Liang.  2014.   Preliminary Application of a framework for modeling habitat suitability and distribution of stream fishes with field testing.  Final Report submitted to U.S. Geological Survey. Reston, Virginia.  24 pp.

Huang, J., E.A. Frimpong, and D.J. Orth. 2016. Temporal transferability of stream fish distribution models: can uncalibrated SDMs predict distribution shifts over time? Diversity and Distributions 1-12.  DOI: 10.1111/ddi.12430
Jenkins, R.E., and N.M. Burkhead.  1994.  Freshwater fishes of Virginia.  American Fisheries Society, Bethesda, Maryland.  1037pp.
Jones, R.N., D.J. Orth, and O.E. Maughan. 1984.  Abundance and preferred habitt of the leopard darter, Percina pantherina, in Glover Creek, Oklahoma.  Copeia 1984:378-384

Near, T.J. 2002.  Phylogenetic relationships of Percina (Percidae: Etheostomatinae). Copeia 2002(1):1-14.

Near, T.J., C.M. Bossu, G.S. Bradburd, R.L Carlson, R.C. Harrington, PR. Hollingsworth, Jr., B.P. Keck, and D.A. Etnier.  2011.  Phylogeny and temporal diversification of darters (Percidae: Etheostomatinae).  Systematic Biology 60(5):565-595.  doi: 10.1093/sysbio/syr05