Stripetail darter

Stripetail darter
Conservation status
Least Concern  (IUCN 3.1)[1]
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Actinopterygii
Order:	Perciformes
Family:	Percidae
Genus:	Etheostoma
Species:	E. kennicotti
Binomial name
Etheostoma kennicotti Putnam, 1863

The stripetail darter (Etheostoma kennicotti) is found in tributaries of the Ohio, Tennessee, and Cumberland Rivers throughout Illinois and Kentucky. It is also found in the Paint Rock River system which runs through Alabama,^[2] and is one of the 324 fish species found in Tennessee.^[3]

Introduction

The stripetail darter males are golden orange and as adults can grow up to 2.8 inches long. It also has black bands present on the caudal fins and soft dorsal fins. The stripetail darter typically nests on the underside of slabrocks in shallow pools with egg numbers ranging from 50 all the way up to 500. Eggs from the stripetail darter range from 1.9 to 2.5mm and are adhesive. Newly hatched stripetail darters are typically around 4.1 to 4.7mm in length and have fully developed pectoral fins with 12 incipient rays.^[4] At this point in time there do not seem to be any management strategies enacted specifically for the purpose of preserving this particular species. However, due to the fact that stripetails breed in shallow pools, siltation would probably have an affect on their breeding abilities. Eggs need oxygen to survive and siltation poses the threat of suffocating the darter’s eggs. The typical effects of human pollution and streamside destruction have the worst impacts on the stripetail darter. Therefore, the best way to keep stripetail darters from going into decline is to enforce the need for streamside management zones and reduce or eliminate point source pollution in streams.

Geographic Distribution

The stripetail darter (Ethestoma kenicotti) is a small, benthic freshwater fish that inhabits river tributaries. Historic or native geographic range of the stripetail darter is likely similar to its current range. Currently, the stripetail darter inhabits tributaries of the Ohio, Tennessee, Cumberland, and Paint Rock river systems. The Green River drainage in Kentucky also contains a population of Stripetail darters.^[5] The Paint Rock river system and Ohio River systems hold the largest populations of the species and it is less common throughout the Tennessee river system. States in which the stripetail darter inhabits include the following: Tennessee, Ohio, Kentucky, Illinois, Alabama, Georgia, and Mississippi.^[6] Stripetail darter’s distribution is typically spotty throughout its range with multiple subpopulations; however, the species is still abundant overall. Page and Smith discovered that the species also varies slightly depending on where the subpopulation of the species occurs.^[7] The reason for this isolation of the populations could be due to climate effects such as low temperatures and low water levels.^[8] The current estimated population is over 10,000 individuals through the range of this fish. It is also important to note that the population is remaining stable and does not seem to be diminishing at any rate.^[6]

Ecology

Ecologically the stripetail darter has many important considerations including its diet, predators, microhabitat, and other biotic and abiotic factors that influence it. The diet of the stripetail darter includes mayflies, fishflies, midge larvae, isopods, stoneflies, cladocerans, isopods, and stoneflies.^[2] Stripetail darters are able to live in a wide range of PH levels and water temperatures.^[9] Typically these darters also live in slab pools in streams and headwaters.^[10] Manmade structures such as dams may now inhibit this species from being able to spread out its distrubution. With hundreds of dams located in Tennessee alone it becomes difficult for fish to spread out into new habitats because they are blocked from getting there. Another manmade limiting factor for these fish may come from the introduction of exotic plants and animals. Exotic fish can especially add pressure to the stripetail darter through competition and predation.

Life History

The breeding season for the stripetail darter in lower Ohio River tributaries begins in late Mach to early April and continues until late May. The temperatures that stripetail breed in are between 14 and 20 degrees Celsius. Stripetail darter eggs are small, about 2.1mm in diameter, spherical and adhesive.^[4] The eggs are usually laid under slabrocks in medium sized or smaller streams that feed into larger bodies of water. The slabrocks provide shelter and protection for the eggs and allow males to guard them more efficiently.^[2] The stripetail also prefers over hanging vegetation to be present near the spawn sites and gravel or sandy bottoms.^[6] The stripetail darter lays anywhere from 50 to 400 eggs at a time. After it’s born it takes around one year for the stripetail to reach sexual maturity. The maximum lifespan of this fish is 3 years.^[2]

Current Manangement

As of right now there are no management plans in place specifically aimed at the conservation of the stripetail darter. They are not listed on the endangered species list and their populations are considered stable. It is estimated that over 10,000 are alive in the wild today and this number is high enough for sustainability.^[6] While there are no specific practices used to conserve the species at this time there are multiple ways humans can reduce their impacts on streams and continue the preservation of all freshwater life. For instance, no-till farming is a good practice for reducing erosion. This is especially critical for those who farm near streams or have manmade headwaters like many farmers have in the Midwest.^[11] The reason no-till farming helps is because it reduces erosion that causes water siltation which wreaks all kinds of destruction on freshwater life. For instance, siltation is a big part of the reason for the decline of ashy darters (Etheostoma cinereum).^[12] Because small fish eggs are especially susceptible to siltation it is important to prevent it from occurring. Another way to prevent sedimentation includes establishing Stream Management Zones in logging areas near perennial and intermittent streams. The elimination of pollution and the use of chemicals such as DDT can also ensure the survival of the stripetail darter. These two things are often responsible for many cases of diseased freshwater wildlife. A final concern would be with exotic species. The introduction of exotic species to places where stripetails live could possibly wipe them out through competition.

Management Recommendations

The first thing that should be done to help manage the current population of stripetail darters is a more accurate population count. Right now it is estimated that there are over 10,000 individuals, but that number should be refined to help determine the best management practice. In order to calculate just how many stripetail darters exist in the wild, seining should be used. Kick seining has already proved to be an effective method for collecting benthic fish and most fish collected can be released.^[10] The seining should be done everywhere there are known populations of the stripetail darter. Calculations from the densities can then be made to obtain an accurate number of the whole population size. Ideally this would also occur at least once every few years. After obtaining numbers on the populations size of the stripetail darter I recommend efforts be put in place to protect its habitat. Because darters are susceptible to many anthropogenic disturbances such as siltation, dredging, and impoundments, it is important these things be reduced as much as possible.^[10] This can be done through public awareness and regulations such as the establishment of stream management zones. Stream management zones provide buffers around streams that hold wildlife. The buffers then help reduce siltation, provide bank stability, and regulate water temperatures.

References