Etheostoma brevirostrum
Encyclopedia
The common name of Etheostoma brevirostrum is the holiday darter. It is one of the 324 fish species found in Tennessee
Tennessee
Tennessee is a U.S. state located in the Southeastern United States. It has a population of 6,346,105, making it the nation's 17th-largest state by population, and covers , making it the 36th-largest by total land area...

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Abstract/ Introduction

This paper is a description of a proposed monitoring program for the Holiday Darter (Etheostoma brevirostrum). The geographical distribution of Ethostoma brevirostrum is confined to the southeast North American water system. There are disjunctive populations throughout Alabama, Georgia, and Tennessee. It is also located in the Coosa River Watershed which begins in Tennessee and Georgia, then enters Alabama. The quantitative diet of the Holiday Darter is close to other members of the sub-genus Ulocentra. Most of the diet consists of small bugs and insects, which includes but is not limited to midges, black fly larvae and small crustaceans. There are two sub-species of Holiday Darters, according to Byron Freeman, Seth Wenger, Sarah McClurg, and Carrie Straight, and they inhabit small to medium sized gradient rich streams. They are often found in streams with large boulders, gravel, cobbles and sand. They can be found in the margins between these large boulders but will use the boulders for protection from predators. The streams where they will be found will have swift to fast moving currents. The streams large boulders will provide area for the females to attach eggs to for reproduction. The Holiday Darter has very vibrant coloration but will display even more brilliant coloration during or before spawning. Spawning for Etheostoma breviostrum takes place during the spring, usually around April or May. This species is state listed in Georgia as a threatened species. One of the disjunct populations is located in the Talladega National Forest which results in it being projected from human encroachment. The separate populations can make it difficult to determine the exact population count. In order to take advantage of the swift moving currents, using seine nets would be the most effective way to capture these Darters and make accurate population counts.

Geographical Distribution of Species

The geographical distribution of Etheostoma brevirostrum is confined to the southeastern United States. According to the U.S. Fish and Wildlife Service, E. brevirostrum is known or is believed to have populations in Alabama, Georgia, and Tennessee. It is known for its populations in the Consauga River and the upper Coosa river system. E. brevirostrum is only known to populate four different river systems. Along these four different river systems, it has only been observed at about 18 different locations. It is believed to be extirpated in portions of its current range. However, it is believed to have a stable population in the upper shoal creek and Consauga River. The Consauga River range extends from Murray County, Georgia to Polk County, Tennessee, as stated by C.E. Johnson and K.B. Damon of the Southern Research Station in Oxford, Mississippi. E. Brevirostrum is “Possibly extirpated from the Calhoun County, Alabama section of Shoal Creek due to impoundments.” (Johnston and Damon) This shows us that E. brevirostrum is highly affected by barriers that prevent movement throughout a water system. Population counts are spotty and have a wide range of results. Snorkeling has been a common method to take population counts. In the past, population counts at a single site have “Resulted in 1, 15-36, 3-13 and 4-10 individuals.” (Johntson and Damon) These inconsistent population counts make it difficult to determine an exact population counts.

Ecology

E. brevirostrum is known for eating “…aquatic insect larvae and micro crustaceans.” (Geological Survey of Alabama), according to the geological Survey of Alabama. It prefers a habitat in relatively shallow water, which is normally between 22-34 cm. E. brevirostrum can be found in areas with cobbles, large boulders, gravel substrate and is often found in clear streams. It prefers a water velocity that is relatively fast and ranges from” 0.54- 0.81” (Shute and Johnston). The boulders that are present in these habitats are often covered with moss. Sand and river weed are also common in these habitats
E. Brevirostrum can be found in rocky runs and pools that contain riffles. It is known to inhabit cool to warm creeks that are small to medium in size. Predators of E. brevirostrum are mostly larger predatory stream fish, however there are no predators that are known for specifically targeting brevirostrum. Threats to its population include dam construction that prevent movement and effect water quality in a stream. Also, threats include sedimentation that occurs from logging and road building. Removal or damage to the riparian zones are known to be detrimental to population counts. "...small changes in stream conditions,such as hydrology, storm flow, impervious surface cover, and bank height, have been demonstrated to affect minnow and darter populations" (Philips and Johnston).

Life History

Breeding for Etheostoma brevirostrum is much like other members of Ulocentra. They will breed in the same area in which they live. In other words, they are not known for migration or habitat movement in order to spawn. Spawning for E. brevirostrum will occur in early spring around April and May. According to Carol E. Johnston and J.R. Shute., often the male positioned himself over or to the side of the female as they moved over the substrate.”(Johntson and Shute) Once the female finds a suitable area for egg placement, the male will exchange the gametes. The female will usually pick an area in between cobbles or in a crevice to attach the eggs. E. brevirostrum has demonstrated territorial behavior when approached by other males during the spawning process. There is not any parental care observed after the eggs have been attached to the cobbles, according to Johnston and Shute. The average lifespan is typically about four years and they will reach sexual maturity within the first year of life. Sedimentation that settles on rocks can make it difficult for the eggs to be attached and in turn can hurt the reproduction rates. Directly before or during spawning, males will display more vibrant colors than at other times of the year. According to Jennifer M. Gumm and Tamra C. Mendelson, there are "...four discrete color classes in darters; red, orange, yellow, blue/green." During spawning, these colors are more vibrant and bright.

Current Management

There are no currently any management plans in effect for E. brevirostrum. However it is a state listed species in Alabama and therefore it is protected under the Non-Game Species regulation. It is not currently a Federally protected fish, however it is proposed to become one. Most of its populations occur in the Talladega National Forest. This provides a large amount of protection and helps to keep their population numbers at a safe number. National forests have riparian streamside management zones which help in the preservation of E. brevirostrum’s preferred habitat. The only management plans in place are the management of watersheds in the Talladega National forest and they ensure that the stream water quality within the forest stays suitable for aquatic communities. Sediment filters are also used in order to prevent sedimentation from occurring and effecting the reproduction of E. brevirostrum.
The implementation of small impoundment is currently the largest threat to E. brevirostrum. According to C.E Johnston and W.W. Hartup, "...impoundments along the creek isolate holiday darter populations." Human induced threats to E. brevirostrum in result in habitat fragmentation and poor water quality. This poor water quality can be a result of direct pollution into a stream or poor agricultural practices by upstream land owners. In order to keep these from being a problem, there needs to be research done on how impoundments in streams negatively affect their populations. Other than the state of Alabama protecting the fish, there are no other agencies that specifically protect Etheostoma brevirostrum.

Management Recommendations

Etheostoma brevirostrum tends to be found in fast moving currents in shallow water. This type of habitat makes it an easy target for seine netting. The fast moving currents would make seine netting very easy in order to take population counts. Also, it can be done with only 3-4 people and causes no destruction to the habitat. The distribution of E. brevirostrum is confined to only 4 streams. Because the distribution is so small, there could be population checks in all of its known habitats. This type of population count could not be done on a species that has a large distribution. E. brevirostrum live to be about 4 years old and will mature within the first year of life. This means that populations will increase every year, therefore population counts should be taken at least annually. Spawning takes place around April and May, so counts should be taken both before and after spawning in order to determine population counts and birth rates. Population counts should be taken around June or July in order to give the yearlings time to hatch and grow large enough in order to be caught by seine nets and are large enough to be accurately identified. E. brevirostrum is not known for being affected by any kind of specific invasive species, so the removal of any invasives would not be effective in helping population counts. The best way to manage E. brevirostrum is to ensure the water quality of the habitat as well as to prevent impoundments from being constructed in its streams.
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