Rhinichthys osculus thermalis
(Hubbs and Kuhne, 1937)
Kendall Warm Springs Dace
T1T1Global Rank
Very high - highThreat Impact
Identity
Unique IDELEMENT_GLOBAL.2.104100
Element CodeAFCJB3705B
Record TypeSPECIES
ClassificationSubspecies
Classification StatusStandard
Name CategoryVertebrate Animal
Endemicendemic to a single state or province
KingdomAnimalia
PhylumCraniata
ClassActinopterygii
OrderCypriniformes
FamilyLeuciscidae
GenusRhinichthys
Concept ReferenceLee, D. S., C. R. Gilbert, C. H. Hocutt, R. E. Jenkins, D. E. McAllister, and J. R. Stauffer, Jr. 1980. Atlas of North American freshwater fishes. North Carolina State Museum of Natural History, Raleigh, North Carolina. i-x + 854 pp.
Taxonomic CommentsThe validity of this subspecies has been questioned, but the distinctive pharyngeal tooth row characteristics of this taxon appear to be genetically controlled and the subspecies evidently is a valid one (Gould and Kaya 1991). Kaya et al. (1992) found distinctive mtDNA in R. osculus thermalis.
Conservation Status
Rank MethodLegacy Rank calculation - Biotics v1
Review Date2019-09-10
Change Date1996-03-18
Edition Date2019-09-10
Edition AuthorsHammerson, G. (2010); rev. R. L. Gundy (2019)
Threat ImpactVery high - high
Range Extent<100 square km (less than about 40 square miles)
Number of Occurrences1 - 5
Rank ReasonsConfined to a small spring system in Wyoming with a declining population and threatened by lacking protection from natural resource exploitation and/or the introduction of non-native species or diseases.
Range Extent CommentsThis subspecies range is confined to Kendall Warm Springs, a short tributary of the Green River in Bridger-Teton National Forest, elevation 2,390 meters, near the town of Pinedale, Sublette County, Wyoming. The total habitat includes the small spring area and 984 feet of stream.
Occurrences CommentsThere is only one known population at Kendall Warm Springs, Sublette County, Wyoming.
Threat Impact CommentsCurrent threats have been largely abated in recent decades. Human use for bathing and washing clothes were former threats, but these have been prohibited by the U.S. Forest Service. Formerly, springs were impacted by cattle grazing, and dace were collected for sport-fish bait, but the area is now fenced, and collection is illegal.
Potential future threats include: water table lowering from increased fire frequency or natural resource exploitation; water table rising from construction of a dam and subsequent reservoir; pollution from accidents on the road, herbicide use, runoff, or natural resource exploitation; and introduction of non-native species and diseases. Any one of these threats could be catastrophic due to the limited habitat and geographic range.
Ecology & Habitat
Diagnostic Characteristics
Differs from subspecies yarrowi in having a smaller body, larger head and fins, and fewer scales and fin rays.
Habitat
Occupies about 300 m of spring outflow along the north face of a limestone ridge; constant water temperature of 26-29 C; water slightly alkaline, mineralized, and high in dissolved solids (Binns 1978, Matthews and Moseley 1990). Monkeyflower, moss, sago pondweed, and stonewort are the primary aquatic plants. Dace occur mainly in pools and quiet eddies where plants and debris are present to slow the current and provide escape cover (Spahr et al. 1991). Fry nursery areas are in still water pockets in dense mats of aquatic vegetation (Spahr et al. 1991).
Ecology
Usually in small schools (Matthews and Moseley 1990). Sources of mortality include emigration over a waterfall and into the Green River, and predation by dragonfly nymphs (Gryska and Hubert 1997).
Reproduction
Spawns probably several times per year (Matthews and Moseley 1990). Appears to be reproductively active throughout the year (Gryska and Hubert 1997).
Other Nations (1)
United StatesN1
| Province | Rank | Native |
|---|
| Wyoming | S1 | Yes |
Roadless Areas (5)
Idaho (1)
| Area | Forest | Acres |
|---|
| Bear Creek | Caribou-Targhee National Forest | 118,582 |
South Dakota (1)
| Area | Forest | Acres |
|---|
| Indian Creek | Buffalo Gap National Grassland | 24,666 |
References (11)
- Binns, N. A. 1978. Habitat Structure of Kendall Warm Springs, With Reference to the Endangered Kendall Warm Springs Dace. Wyoming Game and Fish Department, Fisheries Tech. Bull. No. 3.
- Gould, W. R., and C. Kaya. 1991. Pharyngeal teeth in the endangered Kendall Warm Springs dace (RHINICHTHYS OSCULUS THERMALIS). Copeia 1991:227-229.
- Gryska, A. D., and W. A. Hubert. 1997. Observations on the reproduction, sources of mortality, and diet of the Kendall Warms Springs dace. Great Basin Naturalist 57:338-342.
- Jelks, H. L., S. J. Walsh, N. M. Burkhead, S. Contreras-Balderas, E. Díaz-Pardo, D. A. Hendrickson, J. Lyons, N. E. Mandrak, F. McCormick, J. S. Nelson, S. P. Platania, B. A. Porter, C. B. Renaud, J. Jacobo Schmitter-Soto, E. B. Taylor, and M.L. Warren, Jr. 2008. Conservation status of imperiled North American freshwater and diadromous fishes. Fisheries 33(8):372-407.
- Kaya, C. M., et al. 1992. Biochemical genetics and thermal tolerances of Kendall Warm springs dace (RHINICHTHYS OSCULUS THERMALIS) and Green River speckled dace (R. O. YARROWI). Copeia 1992:528-535.
- Lee, D. S., C. R. Gilbert, C. H. Hocutt, R. E. Jenkins, D. E. McAllister, and J. R. Stauffer, Jr. 1980. Atlas of North American freshwater fishes. North Carolina State Museum of Natural History, Raleigh, North Carolina. i-x + 854 pp.
- Matthews, J.R. and C.J. Moseley (eds.). 1990. The Official World Wildlife Fund Guide to Endangered Species of North America. Volume 1. Plants, Mammals. xxiii + pp 1-560 + 33 pp. appendix + 6 pp. glossary + 16 pp. index. Volume 2. Birds, Reptiles, Amphibians, Fishes, Mussels, Crustaceans, Snails, Insects, and Arachnids. xiii + pp. 561-1180. Beacham Publications, Inc., Washington, D.C.
- Page, L. M., and B. M. Burr. 2011. Peterson field guide to freshwater fishes of North America north of Mexico. Second edition. Houghton Mifflin Harcourt, Boston. xix + 663 pp.
- Spahr, R., L. Armstrong, D. Atwood, and M. Rath. 1991. Threatened, endangered, and sensitive species of the Intermountain Region. U.S. Forest Service, Ogden, Utah.
- U.S. Fish and Wildlife Service (USFWS). 1990. Endangered and threatened species recovery program: report to Congress. 406 pp.
- U.S. Fish and Wildlife Service (USFWS). 2015. Recovery Plan for the Kendall Warm Springs Dace (<i>Rhinichthys osculus thermalis</i>). Revision: Original Approved July 12, 1982. U.S. Fish and Wildlife Service, Cheyenne, Wyoming.