“Flame chub”的意思、由来-开放百科全书

The flame chub (Hemitremia flammea) is a species of freshwater fish in the Cyprinidae family found only in the United States. Its range broadly follows the Tennessee River from above Knoxville, Tennessee, to the mouth of the Duck River. Historically the species was found in Kentucky, Tennessee, Alabama and Georgia. The preferred habitat of flame chub is in small flowing streams often associated with springs.

Anatomy and appearance

The flame chub is a short species with a round body form in profile. The head is small, blunt, and rounded. Breeding males are striking, with lower sides that become flame red while their venters remain light. In each individual, the anterior base of the dorsal fin has a red spot, and the light olive back and sides are streaked with golden brown. A dark lateral band runs between the golden stripes, ending in a small but separate spot at the base of the caudal fin. Flame chubs may grow to a maximum of {{convert|7.8|cm|in|sp=us}} long.^[2]

Geographic distribution

This species of fish has been thriving in the southeast for quite some time, particularly noted in the Alabama and Tennessee areas. It should, however, be noted that the conservation status of this fish is very poorly documented, and it could very well exist outside of Tennessee and Alabama, and some sightings have been observed in Georgia. The NatureServe status of this fish is listed to be vulnerable in both states of known habitat. The flame chub is not a fish that one will find in a stagnant lake or a big body of water. These fish prefer to be contained to small, stream fed patches of water that are very keen to disturbance by humans. Some of these disturbances could be in the form of pollution, hydroelectric dam construction, or just regular negligence towards the ecosystem that surrounds us.^[3]

Ecology

The flame chub is extremely vulnerable, as stated previously, to any human activity that disturbs their habitat.^[3] One topic of interest when trying to learn more about the ecology of the flame chub is what it eats. Although there have been little to no published studies done about the stomach contents of the flame chub, we can learn from sister species to get a good educated guess about what the flame chub might eat. A study done in western New York examined the river chub, or Nocomis micropogon. The main predators for small river fish such as this are other bigger fish and birds. The diet of these fish, as conducted from the New York study, showed that out of a sample size of 308 young to old adult river chubs, 70% of the food volume found was various insects. The other 30% of the stomach contents were found to be various Crustacea, Mollusca, plants, and other various small organic materials.^[4]

Information about the specific or preferred habitat for the flame chub can be taken from information given in a very rich area of Northern Alabama. The water was recorded to contain a pH level of about 7-8. The stream would be fed by numerous other smaller streams spanning its entire length. The bottom of the stream should contain some type of limestone, which is usually essential to the formation of these streams. Water should also be clear, flowing over sand or gravel substrate.^[3]

Life history

One Tennessee study of flame chub hatching found that hatching began in early May (and possibly earlier) and continued through late May.^[5] Gravel is a very important factor in the breeding patterns of these fish, as it is necessary for filtration of extremely clean water as well as bottom stability for a species that spends a lot of its time in the benthos area of the stream.^[4]^[6] No data are available pertaining to the species' lifespan.^[2]

Conservation and management

This species is currently listed as near threatened according to the IUCN Red List.(9) A study done near Chattanooga, Tennessee showed that where oxygen levels were high, and where well-forested rocky watersheds were found, that the density of the Flame Chub as well as similar fish were much higher.{{clarify|date=May 2014}}^[7]

Habitat destruction is one of the main causes of the decline of this species.{{citation needed|date=May 2014}} It is sensitive to alteration of its habitat, and is now extirpated from Kentucky, and close to extirpation in Georgia.{{citation needed|date=May 2014}} A 2007 survey in north Alabama recovered flame chubs at only 19 of 53 localities that in the 1960s still had populations.{{citation needed|date=May 2014}} Many sites were obviously degraded by forms of land use change such as putting a stream in a concrete culvert, or paving over part of a stream.

References

1. ^{{cite journal |author=NatureServe |title=Hemitremia flammea |journal=The IUCN Red List of Threatened Species |volume=2014 |page=e.T9920A18234192 |publisher=IUCN |year=2014 |url=http://www.iucnredlist.org/details/9920/0 |doi=10.2305/IUCN.UK.2014-3.RLTS.T9920A18234192.en |access-date=9 November 2017}}
2. ^¹Page, L.M. and B.M. Burr, 1991. A field guide to freshwater fishes of North America north of Mexico. Houghton Mifflin Company, Boston. 434 p.
3. ^¹²Stallsmith, Bruce. 2010. Status of the flame chub Hemitremia flammea in Alabama, USA. Department of Biological Sciences, University of Alabama in Huntsville. Endangered Species Research: 87-93.
4. ^¹Lachner, EA. 1950. The Comparative Food Habits of the Cyprinid Fishes Nocomis bigguttatus and Nocomis micropogon in Western New York. Journal of the Washington Academy of Sciences 40:229-236.
5. ^Bettoli, Phillip W.; Goldsworthy, Cory. 2011. Larval Fish Dynamics in Spring Pools in Middle Tennessee. Southeastern Naturalist: 145-154.
6. ^Etnier, D.A. and W.C. Starnes, 1993. The fishes of Tennessee. The University of Tennessee Press, Knoxville, Tennessee, USA. (pls. check date).
7. ^Long, J; Schorr, MS. 2005. Effects of watershed urban land use on environmental conditions and fish assemblages in Chattanooga area streams (Tennessee-Georgia). Journal of Freshwater Ecology: 527-537.