Trispot darter

From Wikipedia, the free encyclopedia
Trispot darter
Conservation status
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Perciformes
Family: Percidae
Genus: Etheostoma
Species: E. trisella
Binomial name
Etheostoma trisella
Bailey & Richards, 1963

The trispot darter (Etheostoma trisella) is a species of fish in the Percidae family endemic to the United States.

Description

The average length of Etheostoma trisella is 35 mm standard length. It is somewhat short-lived with an average life span around 2.5 years.[2]

Habitat

E. trisella requires two separate but interconnected habitats. When not breeding, it occupies the peripheral zones of the main river, with slow-moving water and silt gravel substrates with vegetation cover. The breeding habitat is much warmer water, and usually is a clay-bottomed substrate with heavy vegetation seepage.[3] The abiotic factor, water temperature, must be warmer around spawning; for example, water at 12°C is best for egg maturation. Another factor is water velocity, because the species lives in the peripheral zones of the main river where water runs slower. Also, E. trisella prefers a silty substrate for egg laying. These factors are believed to cause microdistribution.

Distribution

The trispot darter, Etheostoma trisella, is endemic to the Conasauga River and its tributaries[3] located in northern Georgia and southern Tennessee. The species was thought to be extinct from the historical range for seven years, until a specimen was found in north Georgia in 1967. The historical range was in the Alabama River system and as far south as the Coosa River, and in some Georgia rivers. The species also was found in a reservoir, Lake Weiss. Other recent efforts to find the darter have not been successful; it is now only found in the Conasauga.[3] The reason for the decline in distribution is thought to be due to human impact and development. Silt in water affects egg survival, and correct water temperature is vital for breeding for E. trisella. The Conasauga River offers the critical, undisturbed habitat for the species.[4]

Prey and predators

Chironomidae larvae account for 70% of the diet of this darter; Ephemeroptera nymphs account for another 19%, as measured by examining stomach contents of E. trisella.[4] The species coexists with several other species in its habitat, such as Campostoma anomalum, Fundulus stellifer, and Etheostoma coosa. The only real competitor to E. trisella is E. coosa, because its mouth size and body length allow it to be a threat for food and space. The main natural predators of the species are from the genus Mycropterus.[2]

Breeding

The trispot darters spawn around January through March, with the males showing brilliant colors of skin pigment. The skin color is thought to in attracting mates. Egg clutch numbers vary from 50-300 eggs per female.[4]

Current management

The impact of humans must be reduced to ensure the future of E. etheostoma. Industrial or agricultural runoff allowed in trispot habitat might raise water temperatures and stop reproduction. Loss of habitat is the primaty reason for decline of the fish.[5] The Universities of Tennessee, Georgia, Alabama could use collaborative management to create a plan of action to submit to the agencies, as their researchers have collected most of the data on the species. Because the species is listed as vulnerable, and is still on decline, intervention is needed. Liberal fishing regulations for Micropterus spp. in areas where the two species overlap could take some stress off E. trisella.

References

  1. ↑ NatureServe (2013). "Etheostoma tricella". IUCN Red List of Threatened Species. Version 3.1. International Union for Conservation of Nature. Retrieved November 22, 2013. 
  2. ↑ 2.0 2.1 Etnier, D.A. 1970. Additional Specimens of Etheostoma trisella from Tennessee. Copeia 2:365-400
  3. ↑ 3.0 3.1 3.2 Ryon, M.G. 1986. The Life-History and Ecology of Etheostoma trisella. American Midland Naturalist 115:73-86
  4. ↑ 4.0 4.1 4.2 Ramsey, J.S., and Mount, R. H. 1986. Trispot Darter. Vertebrate animals of Alabama in need of special attention 20-21
  5. ↑ Howell WM, Caldwell, RD 1967.: Discovery of a Second Specimen of Darter Etheostoma trisella. COPEIA 1:235-248

Gimenez Dixon, M. 1996. Etheostoma trisella. 2006 IUCN Red List of Threatened Species. Downloaded on 4 August 2007.

  • Carlson,R.L.,and Wainwright,P.C. 2010. The Ecological Morphology of Darter Fish. Biological Journal of the Linnean Society 100: 30-45
  • Etnier, D.A 1970. Additional Specimens of Etheostoma trisella from Tennessee. Copeia 2:365-400
  • Heins, D.C., Baker J.A., and Guill J.M. 2010. Seasonal and inter-annual components of intra-populations variation in clutch

size and egg size darter. Ecology of Freshwater Fish 19:322-332

  • Howell, WM, Caldwell, RD 1967. Discovery of a Second Specimen of Darter Etheostoma trisella.COPEIA 1:235-248
  • Ramsey, J.S., and Mount, R. H. 1986. Trispot Darter. Vertebrate animals of Alabama in need of special attention 20-21
This article is issued from Wikipedia. The text is available under the Creative Commons Attribution/Share Alike; additional terms may apply for the media files.