TN00156    SLENDER CHUB    HYBOPSIS CAHNI 

Taxonomy

Species ID	TN00156
Name	CHUB, SLENDER
Other Common Names
Category	01 Fish
Elcode
Phylum	CHORDATA
Subphylum
Class	OSTEICHTHYES
Subclass
Suborder
Order	CYPRINIFORMES
Family	CYPRINIDAE
Genus	HYBOPSIS
Species	CAHNI
Subspecies
Authority	HUBBS & CRANE 1956
Scientific Name	HYBOPSIS CAHNI

References

TN5057, 807, 4205, 9286

Status

Status Code	Status Translation	References
102	Federal Threatened	9286
102	Federal Threatened	828
999	See Comments

County Name	Historical Occurrence	Resident Occurrence	General Occurrence	Seasonal Occurrence	Abundance
Anderson	2
Campbell	2
Claiborne	2	2	2	All Seasons	Rare
Grainger	2
Hamblen	2
Hancock	2	2	2	All Seasons	Rare
Union	2

Absent Within Counties	Unknown Within Counties

Hydrologic Unit Code References TN5072, TN5002, TN5008

Quadrangle	Quadrangle Name
3608354	COLEMAN GAP
3608356	MIDDLESBORO SOUTH

Quadrangle Distribution References TN5028, TN5072 Latitude/Longitude 363205N 0832694W, 363392N 0832526W, 363230N 0833750W, 363225N 0833755W

Ecoregion	Ecoregion Name
221100	Mixed Mesophytic Forest
221400	Appalachian Oak Forest

Ecoregion Distribution References TN5002, TN5008, TN5072

River Reach	River Reach Name
0601020516,0	CLINCH RIVER
0601020515,0	CLINCH RIVER
0601020516,1	CLINCH RIVER
060102066,5	POWELL RIVER

River Reach References

Distribution General Comments

General Distribution References

Habitat(s): Aquatic

Comments on General Habitat

This species is restricted to moderate to large size (30-125 m width), warm water streams in which it has been taken only over or very closely adjacent to substrates typically of fine gravel, occasionally with a mixture of coarse sand and medium and large gravel, swept clean by moderate to swift currents *807*. They use open shallow flats and shoals of warm, usually clear, moderate-gradient large streams and rivers, 30-125 meters wide. Frequently the chub is taken as shallow as 0.3 meters, rarely 0.1 meters. They occasionally occupy slow runs, but have not been found in backwaters or pools. A specific habitat requirement appears to be the presence of major areas (greater than 25 square meters) of clean, small (pea size) to medium gravel. Its winter habitat is probably pools *9286*.

General Habitat References

9286, 807

Forest Size Class Association

Forest Size Class Association References

Society of American Forester's Type Associations	Seral Stage	Canopy Closure

References on SAF Type Association

Land Use/Land Cover Associations

Streams and Canals

Water

Streams and Canals

Land Use/Land Cover Association References

TN5002, TN5072, 9286, 807, 787, 821, TN5002

National Wetlands Inventory Associations	Class	Modifier	Special Modifier
Riverine, lower perennial	Unconsolidated bottom, cobble/gravel	Nontidal, permanent	fresh
Riverine	Streambed	Nontidal, permanent	fresh
Riverine	Unconsolidated bottom	Nontidal, permanent	fresh
Riverine, upper perennial	Streambed, cobble/gravel	Nontidal, permanent	fresh
Riverine, upper perennial	Streambed, sand	Nontidal, permanent	fresh
Riverine, upper perennial	Unconsolidated bottom, cobble/gravel
Riverine, upper perennial	Unconsolidated bottom, sand

NWI Association References

TN5002, TN5072, 9286, 807, 787, 821, 4205

Animal/Plant Associations

Animal/Plant Association References

Habitat Evaluation Procedures Comments on HEP

HEP References

Potential Natural Vegetation Associations

Oak-Hickory Forest

Mixed Mesophytic Forest

Oak-Hickory-Pine Forest

Southern Mixed Forest

PNV References

TN5002, TN5008, TN5072

USFS Associations

USFS References

Tennessee Habitat Associations	Habitat Value	Translation

References on TENHAB Association

Habitat Relationships	Special Habitat Relationships

References on Habitat Relationships

Food Habits

Trophic	References
OMNIVORE	TN5072

Lifestage	Food Item Consumed	Part of Food Item
Adult	Bivalve Molluscs	Juvenile stage
Adult	Snails	Adult stage
Adult	Insects	Juvenile stage
Adult	Insects	Adult stage
General	Bivalve Molluscs	Juvenile stage
General	Snails	Adult stage
General	Insects	Juvenile stage
General	Insects	Adult stage
Important	Bivalve Molluscs	Juvenile stage
Important	Snails	Adult stage
Important	Insects	Juvenile stage
General	Ephemeroptera	Larva stage
General	Insects	Larva stage
General	Animals	Larva stage
General	Plecoptra	Larva stage
General	Trichoptera	Larva stage
General	Coleoptera	Larva stage
General	Diptera	Larva stage
General	Bivalve Molluscs	Not Specified
General	Molluscs	Not Specified
General	Animals	Not Specified
General	Snails	Not Specified
General	See Comments on Food Habits	See Comments
Important	Ephemeroptera	Larva stage
Important	Insects	Larva stage
Important	Animals	Larva stage
Important	Trichoptera	Larva stage
Important	Snails	Not Specified
Important	Molluscs	Not Specified
Important	Animals	Not Specified
Important	Diptera	Larva stage
Important	See Comments on Food Habits	See Comments
Adult	Ephemeroptera	Larva stage
Adult	Insects	Larva stage
Adult	Animals	Larva stage
Adult	Plecoptra	Larva stage
Adult	Coleoptera	Larva stage
Adult	Snails	Not Specified
Adult	Trichoptera	Larva stage
Adult	Diptera	Larva stage
Adult	See Comments on Food Habits	See Comments
Adult	Bivalve Molluscs	Not Specified
Adult	Molluscs	Not Specified
General	Insects	Juvenile stage
General	Snails	Adult stage
General	Bivalve Molluscs	Juvenile stage
General	Insects	Adult stage
Important	Bivalve Molluscs	Juvenile stage
Important	Insects	Juvenile stage
Important	Snails	Adult stage
Adult	Insects	Juvenile stage
Adult	Insects	Adult stage
Adult	Bivalve Molluscs	Juvenile stage
Adult	Snails	Adult stage
Adult	Animals	Not Specified

Comments on General Food Habits

The orders or classes of the food items found in the first descending section of the gut included, Gastropoda 36%, Diptera 23%, Trichoptera 18%, Ephemeroptera 16%, Plecoptera 1%, Coleoptera 1%, and Bivalvia 1%. All except two insect items are larvae, and the exceptions are pupae *807*. The data indicates that the species is a fairly general, benthic feeder, feeds during daylight on clean bottom and has good oral or pharyngeal sorting ability, and/or is an efficient 'food picker' *807*. This species locates food primarily by sight, enhanced by taste *790,823,9286*.

Comments on Adult Food Habits

The orders or classes of the food items found in the first descending section of the gut included Gastropoda 36%, Diptera 23%, Trichoptera 18%, Ephemeroptera 16%, Plecoptera 1%, Coleoptera 1%, and Bivalvia 1%. All except two insect items are larvae, and the exceptions are pupae *807*. The data indicates that this species is a fairly general, benthic feeder, that feeds during daylight on a clean bottom, has good oral or pharyngeal sorting ability, and/or is an efficient 'food picker' *807*. locates food primarily by sight, enhanced by taste *790,823*

References/Lifestage	Reference Numbers
General	TN5072, 9286, 807, 821
Adult	TN5072, 807, 821
Important	TN5072, 807, 821

Environmental Associations

Lifestage	Environmental Association
Adult	Bottom Type [Aquatic]: Gravel
Egg	Bottom Type [Aquatic]: Gravel
General	Bottom Type [Aquatic]: Gravel
General	Flow: Medium streams [50-1000 cfs mean annual flow]
General	Flow: Large streams [1000-5000 cfs mean annual low]
General	Flow: Rivers [greater than 5000 cfs mean annual low]
General	Water Velocity [Instream Flow Group Increments]: Specified in Comments
Limiting	Bottom Type [Aquatic]: Gravel
General	Turbidity: Clear water
General	Turbidity: Clear water but tolerate periodic cloudiness
General	Turbidity: Specified in Comments
General	Substrate: Sand
General	Substrate: Rocks
General	Relation to Substrate: Unattached - normally free living
General	Bottom Type [Aquatic]: Sand
General	Bottom Type [Aquatic]: Pebble
General	Bottom Type [Aquatic]: Gravel
General	Bottom Type [Aquatic]: Specified in Comments
General	Aquatic Vegetation [specified type]: Specified in comments
General	Flow: Medium streams [50-1000 cfs mean annual flow]
General	Flow: Large streams [1000-5000 cfs mean annual low]
General	Flow: Specified in Comments
General	Water Level: Permanently flooded areas
General	Reservoir Water: Specified in Comments
General	Water Depth Preference: Specified in Comments
General	Aquatic Features: Specified in Comments
General	Inland Wetlands: Inland open fresh water
Limiting	Turbidity: Clear water
Limiting	Turbidity: Clear water but tolerate periodic cloudiness
Limiting	Turbidity: Specified in Comments
Limiting	Water Temperature: Specified in Comments
Limiting	Reservoir Water: Specified in Comments
Limiting	Flow: Medium streams [50-1000 cfs mean annual flow]
Limiting	Flow: Large streams [1000-5000 cfs mean annual low]
Limiting	Substrate: Sand
Limiting	Substrate: Rocks
Limiting	Bottom Type [Aquatic]: Sand
Limiting	Bottom Type [Aquatic]: Pebble
Limiting	Bottom Type [Aquatic]: Gravel
Limiting	Water Velocity [Instream Flow Group Increments]: Specified in Comments
Egg	Turbidity: Clear water
Feeding Adult	Turbidity: Clear water
Breeding Adult	Turbidity: Clear water
General	Gradient: Specified in Comments
General	Gradient: Moderate
General	Elevation: 1000-2000 ft.
General	Elevation: Specified in Comments
General	Water Depth Preference: Less than 1 ft.
General	Water Depth Preference: 1-5 ft.

Comments on General Environmental Associations

00170S=MODERATE TO HIGH CURRENT

Comments on Limiting Environmental Associations

0

References/Lifestage	Reference Numbers
General	TN5002, TN5072, 9286, 807, 787, 821
Limiting	TN5002, TN5072, 807
Breeding Adult	TN5002, TN5072, 807
Feeding Adult	TN5002, TN5072, 807
Resting Adult	TN5002, TN5072
Egg	TN5002, TN5072, 807

Life History

Physical description: The maximum known length of this species is 77 mm standard length (see comments), with a 94 mm total length. The body form is moderately elongate, the snout elongate and the eye large and supralateral. The mouth is inferior, with one pair of terminal labial barbels. The fins are normal, and not falcate or well-rounded. The dorsal origin is over or slightly posterior to the pelvic origin. The scales are moderate to large in size, and the coloration in preservative dark above, and light below, with a dark lateral stripe on the body located just below and a somewhat pale dorsolateral stripe. Just above and below each lateral line pore is a single, short, linear, black punctuation. The punctuations are usually masked on the urosome by the dark stripe. The caudal spot is moderate in size, ovoid, and slightly disconnected or confluent with a lateral stripe. In life, they are black olive, with silvery sides and a white venter. Diagnostic characteristics of juveniles and adults include lateral line scales numbering 40-49. Spots (except caudal) and blotches absent from the body and fins. The posterior half of the lateral stipe is usually interrupted at the edge of each myomere by a V-shaped pale dash whose angle points anteriad, forming a horizontal series of 'chevrons'. Only males develop small to minute breeding tubercles on the dorsal and lateral parts of the head, and the dorsal and lateral body. Pectoral fin rays number 2-10, and pelvic rays 2-6. The nuptial male also has a flat pad of corneous tissue on the the cheek *830,807,794,4205*. Reproduction: Spawning probably occurs in May, possibly beginning in mid or late-April of some years *4205*. The age of 75 specimens aged by scales, showed mature April specimens were in their third (55-58 mm standard length) or fourth (71 mm standard length) year of life (age groups 2 and 3). It is highly unlikely that age group 1 specimens are mature. Probably few specimens survive beyond the fourth year of life *807*. Reproductive habitat likely is that typically occupied by adults during warmer parts of the year as that is where nuptial specimens were found. Spawning behavior is probably similar to that of H. insignis *9286*. Behavior: Reproductive behavior is unknown, but non of its close relatives are known to construct nests or exhibit parental care *807*. Of 14 young to adult fish, 12 consumed mostly or entirely insect larvae, chiefly mayflies, caddisflies, and trueflies (midges). Three had taken large numbers of tiny snails, and two had ingested one minute Asiatic clam, Corbicula. The slender chub may be a more visual feeder than other species of Erimystax *9286*. Origin: This species is endemic to the upper Tennessee River in Tennessee and in Virginia *830*. Limiting factors: Impoundments, changing streams to lacustrine environments, the release of cool to cold reservoir water, inhibiting or preventing reproduction and possibly limiting food supply limit the range of this species. Possibly the removal of gravel from shoals, the only known species habitat, may also limit this species. They may survive moderate periods of turbidity and siltation, however, siltation may cause a reduction in the food supply and egg viability *807*. Coal related situation, poor land use practices, gravel dredging and toxic chemical spills are also threatening factors *830*. Interspecific competition with numerous associated fish species may also limit this species. There is a possibility of intense competition with Hybopsis insignis, another species of subgenus Erimystax (it occupies Powell River down to Norris Reservoir, Tennessee) *807*. Population parmeters: Although a few fish have been scale-aged at three+ years it is now thought that they may be a year younger suggesting a maximum age of 2 years and a few months *9286*. PHYSICAL DESCRIPTION: ELONGATE CHUB WITH LONG DISTINCTIVE SNOUT, BARBELS AT POSTERIOR TIPS OF THE MAXILLARY, MAXIMUM LENGTH 3 INCHES, ANAL RAYS 6-7, LATERAL LINE SCALES ABOUT 45 OTHER: GRAVID FEMALES HAVE BEEN COLLECTED IN MAY OVER SHOAL AREAS, FREQUENTS GRAVEL SHOALS, INHABITS DEEPER POOLS DURING COOLER MONTHS

Life History

References for Life History Codes

9286, 830, 807, 794, 4205, TN5002, TN5072

Comments on Life History Codes

The standard length is that length of a given fish from the tip of its snout to, but not including, its caudal fin *2208*.

Management Practices

Result	Management Action
Adverse	Developing/maintaining water holes, ponds, potholes, etc.
Adverse	Channelization
Adverse	Construction of navigational improvements [dams, locks, etc.]
Adverse	Dredging
Adverse	Deposition of fill
Adverse	Timber harvesting - clearcutting
Beneficial	Providing artificial nesting/spawning sites
Beneficial	Developing/maintaining stream bank vegetation
Beneficial	Maintaining/protecting riparian habitats
Beneficial	Controlling sedimentation
Beneficial	Controlling pollution [thermal, chemical, physical]
Beneficial	Controlling wind and water erosion
Beneficial	Maintaining streams
Beneficial	Restricting/regulating human use of habitats
Beneficial	Restricting/regulating human disturbance of populations
Beneficial	Public education - publicity
Beneficial	Public education - law enforcement
Beneficial	Maintaining/protecting riparian habitats
Beneficial	Controlling sedimentation
Beneficial	Controlling pollution [thermal, chemical, physical]
Beneficial	Proper handling and placement of overburden and spoil materials
Beneficial	Other management practices [specified in comments]
Adverse	Mechanical manipulation of stream bottoms
Adverse	Dredging
Adverse	Creating impoundments
Adverse	Clearing/snagging
Adverse	Surface mining
Adverse	Underground mining
Adverse	Other management practices [specified in comments]
Beneficial	Regulating harvest of species being described
Beneficial	Maintaining undisturbed/undeveloped areas
Beneficial	Transplanting wild animals
Beneficial	Stocking captive-reared domestic-strain animals
Beneficial	Regulating harvest - setting age limits
Beneficial	Harvest of species usinf non-selective gear
Beneficial	Harvest of species using benthic disturbing gear
Beneficial	Public education - law enforcement
Beneficial	Public education - incentive payments
Beneficial	Public education - publicity
Beneficial	Mariculture activities
Adverse	Restricting/regulating human disturbance of populations
Adverse	Installing protective nets
Adverse	Regulating commercial harvest levels

References/Result	Reference Numbers
Adverse	TN5002, TN5072, 830, 807
Beneficial	TN5002, TN5072, 9286, 830, 807

Comments on Management Practices

Tennessee Narrative STOP OR CONTROL COAL MINING AND GRAVEL DREDGING Virginia Narrative The Clinch and Powell Rivers (Scott and Lee Counties, Virginia) should be maintained in as near natural condition as possible. The streams merit scenic river status *830*. The feasibility of introducing this species back into the Holston River should be determined *830*. General collecting of species should be allowed only by special permit, in order that collectors are clearly cognizant of potentially harmful effects of overharvest and substrate disturbance *807*. Impoundments, changing streams to lacustrine environments, and the release of cool to cold reservoir water, will inhibit or prevent reproduction and possibly limit food supply. They may survive moderate periods of turbidity and siltation, however, siltation may cause a reduction in food supply and egg viability *807*. Coal related situation, poor land use practices, gravel dredging and toxic chemical spills are also threatening factors *830*. Recovery plans of U.S. Fish and Wildlife Service are designed to protect and recover species until a minimum of seven population centers exist on the Clinch and Powell Rivers and viable populations are established at two locations on the Holston River *830*.TN00156STOP OR CONTROL COAL MINING AND GRAVEL DREDGING

References

787* Burkhead, N.M., Jenkins, R.E. 1982. Five-year status review 
of the slender chub, Hybopsis cahni a threatened cyprinid fish 
of the Upper Tennessee drainage. Rep. Fish and Wildl. Serv., 
Newton Corner, Mass:27.

794* Hubbs, C.L., Crowe, W.R. 1956. Preliminary analysis of the 
American cyprinid fishes, seven new, referred to the genus 
Hybopsis, subgenus Erimystax. Occas. Paper, Mus. Zool. Univ. 
Michigan, Ann Arbor:8.

807* Jenkins, R.E. 1975. Hybopsis chani (Hubbs and Crowe), 1956. 
UNPB,:30.

821* Parker, W., Dixon, L. 1980. Endangered and Threatened 
Wildlife of Kentucky, North Carolina, South Carolina and 
Tennessee. U.S. Fish and Wildl. Serv., Washington, D.C:45.

828* Service, U.S. Fish and Wildlife. 1983. Republication of the 
lists of endangered and threatened species. Federal Register 
17.11-17.12.:1-24.

830* Serv., U.S. Fish and Wildl. 1982. Recovery plan for slender 
chub (Hybopsis cahni Taylor). (draft). U.S. Fish and Wildl. 
Serv., Washington, D.C:25.

4205* Jenkins, R.E. 1984. Fishes of Virginia (tentative)..

9286* Virginia Dept. Game Inland Fisheries. 1988. Proceedings of 
symposium on species of special concern in Virginia. In Press,.

TN5002* Eagar, D. and R.H. Hatcher, editors. 1980. Tennessee's 
rare wildlife Volume I: the vertebrates. Tennessee Wildlife 
Resources Agency, Nashville, TN.

TN5008* Tennessee Natural Heritage Program Data Base. Tennessee 
Dept. of Conservation, Ecological Services Division, Nashville, 
TN.

TN5028* Ligon, J.D., 1970. Behavior and feeding biology of the 
red-cockaded woodpecker. Auk 87: 255-278.

TN5057* Etnier, D.A. unpublished. Fishes of Tennessee. 
University of Tennessee, Knoxville, TN.

TN5072* Lee, D.S., C.R. Gilbert, C.H. Hocutt, R.E. Jenkins, D.A. 
McAllister, and J.R. Stauffer, Jr. (editors). 1980 et seq. Atlas 
of North American Freshwater Fishes. N.C. State Museum of 
Natural History, Raleigh, NC.