Least darter

Last updated

Least darter
Least darter.jpg
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Perciformes
Family: Percidae
Genus: Etheostoma
Species:
E. microperca
Binomial name
Etheostoma microperca

The least darter (Etheostoma microperca), is a species of freshwater ray-finned fish, a darter from the subfamily Etheostomatinae, part of the family Percidae, which also contains the perches, ruffes and pikeperches. It is generally found in lakes and streams in northeastern part of the United States and along the Mississippi River systems.

Contents

Description

E. microperca fish are very small in body size, typically are 25–35 mm (1–1+3⁄8 in) long with a maximum of about 45 mm (1+3⁄4 in). [2] Their main color is an overall light olive brown covered in darker brown speckles. The lateral line is often absent, or when it is present, it is very short. They have seven to 15 dark blotches along their sides which are wider than they are tall. The second dorsal and tail fins have many small dark spots that form wavy rows. E. microperca also has a distinct teardrop-shaped spot under the eyes and often several other dark lines radiating outward from the eyes on their heads and snouts. The breeding males have a band of red spots in the middle of their first dorsal fins. Males also have oversized pelvic fins, and their pectoral, pelvic, and anal fins are flushed with orange or red. The females look very similar to males, but are lacking any of the red or orange and have smaller pelvic fins. [3] Their fins are spotted and lightly pigmented. They have a fusiform to cylindrical body shape that is slightly elongated and are slightly laterally compressed anteriorly and are round to oval in cross section. In perciform teleosts, the posterior, exposed part of each scale bears tiny tooth-like projections (cteni) – ctenoid scales. This species has 32–38 of these ctenoid lateral scales. Their tails, dorsal fins, and other fins are rounded or squared. The dorsal fin has two lobes, slightly separated, the first with five to seven spines and the second with 9–10 rays. The pelvic fins are thoracic, and their anal fins have one or two spines and five or six rays. [2] The pectoral fins in this darter species may function in vertical movement, as well as in low-speed maneuvering, as these fish lack swim bladders. Their pectoral fins can also be used for braking and may be used to maintain position in strong currents. Therefore, these pectorals have multiple functions and make pectoral fin length an equivocal habitat indication for the bladderless darters. [4]

Distribution and habitat

The fish species, Etheostoma microperca, is distributed across the northeastern part of the United States, particularly in the midwest. This fish is also one of the 324 fish species found in Tennessee, and has been found in other states, such as Minnesota, Illinois, and Ohio, and many others. As of 2008, it had been documented at a limited number of sites across the southern two-thirds of Minnesota, but most of its populations occurred in the west-central portion of the state in the Otter Tail River and upper Mississippi River drainages. [5]

Adults of E. microperca are usually found in streams near vegetation, such as along overhanging grassy banks and among filamentous algae. Juveniles are mainly found in thick growths of algae along the edges of streams. These fish are rarely found in midstream or away from vegetation; they are found exclusively near the edges of streams in quieter water to avoid the strong currents. [6] They mainly reside in natural lakes and permanent wetlands that contain large amounts of aquatic vegetation and clear waters. [7]

Diet

Adapted for feeding on prey active on and around plants, the species has a terminal mouth, orienting the opening towards prey anterior to the fish. With its long peduncle, long pectoral fins, and laterally compressed body, E. microperca is able to be fast and efficient in capturing its prey. The preferred prey are Batidae nymphs, Tanytarsini (e.g. Tantarsus) and Orthocladiinae (e.g. Corynoneura, Cricotopus). Small items, such as microcrustaceans and Chironomidae, are also important in the diet of E. micoperca. These prey are very small, as this particular species is very small itself in body size and mouth. [4]

Lifecycle

E. microperca will migrate from the deeper pools of streams to shallow, weedy habitats from March to May. During spawning, males develop three-dimensional territories of about 30 cm (12 in) in diameter and defend them from other males. Females enter a male's territory and spawn on pieces of aquatic vegetation. Females will travel through many males' territories and can lay about 30 eggs per day. [8] Least darters are a short-lived species; in Minnesota, they live 2–3 yr. [9] By early January, the male's genital papilla begins to swell, and by late March or early April, the testes are enlarged and sexually mature. They also develop lateral flaps of skin on their pelvic fins as early as late January, and by mid-March their breeding colors are evident. The female's genital papilla is also enlarged up to the spawning period, but her color and pattern changes very little. Over time, ova develop into eggs. The spawning position of E. microperca is almost always vertical; horizontal positioning during successful egg-laying is only occasionally observed. Males tend to spawn with several females. [10] Males also guard small territories from other males and also guard the eggs until they hatch. [3]

Conservation

Habitat loss and degradation are the greatest threats to least darter populations. They are vulnerable to pollution, pesticides, agricultural and urban runoff, eutrophication, and loss of habitat elements, such as low-velocity waters and aquatic vegetation. Other potential threats to this species include loss of forested habitats around streams, stream reclamation, and the introduction of non-native and predatory fish species. Maintenance of high-quality water systems is recommended for this species. Water systems with large populations of least darters should be protected from human disturbances and development.

Conservation efforts in Minnesota

Prior to 1990, the least darter was known from 31 sites in 10 streams and 9 lakes scattered across the southern three-fourths of the state. Surveys from 1990 to 2002 added 47 sites in 9 new streams and 41 new lakes, mostly in the Otter Tail River system and the upper Mississippi River drainage. A collection from Long Lake on the border of Itasca and St. Louis Counties was the first record of the least darter in the Lake Superior drainage. Surveys completed by the Minnesota County Biological Survey from 1997 to 2008 found new sites for this species, but also found some historical sites had been lost in highly developed areas. More thorough sampling is needed to obtain accurate population estimates. Additionally, the identification of specific environmental stressors is needed to further understand how to aid the fish populations. Genetic analysis may also aid in the conservation of this rare species. Currently, no specific management plans are in use for the least darter in Minnesota. [7]

Related Research Articles

<span class="mw-page-title-main">Bluegill</span> Species of fish

The bluegill, sometimes referred to as "bream", "brim", "sunny", or, as is common in Texas, "copper nose", is a species of North American freshwater fish, native to and commonly found in streams, rivers, lakes, ponds and wetlands east of the Rocky Mountains. It is the type species of the genus Lepomis, from the family Centrarchidae in the order Perciformes.

<span class="mw-page-title-main">Johnny darter</span> Species of fish

The johnny darter is a species of freshwater ray-finned fish, a darter from the subfamily Etheostomatinae, part of the family Percidae, which also contains the perches, ruffes and pikeperches. It is native to shallow waters throughout North America east of the Rocky Mountains.

<span class="mw-page-title-main">Vermilion darter</span> Species of fish

The vermilion darter is a species of freshwater ray-finned fish, a darter from the subfamily Etheostomatinae, part of the family Percidae, which also contains the perches, ruffes and pikeperches. It is endemic to the southern United States, where it only is found in Turkey Creek in Jefferson County, Alabama, part of the Mobile Bay drainage basin. It was first described by Herbert Boschung in 1992, who was the curator of ichthyology at the University of Alabama, along with biologist Richard Mayden and scientific illustrator Joseph Tomelleri. On December 7, 2010, the US Fish and Wildlife Service designated 13 mi (21 km) of Turkey Creek watershed as critical habitat for the darter. According to the IUCN, the population of this fish is declining.

<span class="mw-page-title-main">Fantail darter</span> Species of fish

The fantail darter is a species of freshwater ray-finned fish, a darter from the subfamily Etheostomatinae, part of the family Percidae, which also contains the perches, ruffes and pikeperches. It is widely distributed across streams in North America.

<span class="mw-page-title-main">Finescale dace</span> Species of fish

The finescale dace is a species of freshwater fish in the family Cyprinidae of order Cypriniformes. It is native to the northern portions of Minnesota, with relatively smaller populations in northern New York, Vermont, New Hampshire, and Maine.

<i>Etheostoma exile</i> Species of fish

Etheostoma exile, the Iowa darter, is a species of freshwater ray-finned fish, a darter from the subfamily Etheostomatinae, part of the family Percidae, which also contains the perches, ruffes and pikeperches. It is native to the lakes and streams of Iowa, along with about 17 other species of darters.

<span class="mw-page-title-main">Mud darter</span> Species of fish

The mud darter is a species of freshwater ray-finned fish, a darter from the subfamily Etheostomatinae, part of the family Percidae, which also contains the perches, ruffes and pikeperches. It is endemic to the lowlands of the Mississippi River basin from Wisconsin and Minnesota south to Louisiana and East Texas. It is also found in the drainages of the Sabine and Neches Rivers of Texas and Louisiana. It can be found in slow-moving waters on riffles in rivers, as well as in creeks, swamps, lakes, and reservoirs. It mostly consumes the larvae of midges and blackflies. This species can reach a length of 7.1 cm (2.8 in), though most only reach a length of 5 cm (2.0 in).

The corrugated darter is a species of freshwater ray-finned fish, a darter from the subfamily Etheostomatinae, part of the family Percidae, which also contains the perches, ruffes and pikeperches. It is endemic to the eastern United States only known from Caney Fork, Tennessee, where it has been shown to have as many as five subgroups. They are active hunters which prey on insects, fry, and possibly young snails. Multiple species and subspecies of these darters can coexist where substrate is varied, so this must be carefully preserved to accommodate many similar species. With the warming of spring, E. basilare enters its breeding cycle and males develop their dimorphic coloration. Like most darters, it hugs the stream bed, using its body shape and fin posture to maintain its position.

<span class="mw-page-title-main">Bluntnose darter</span> Species of fish

The bluntnose darter is a species of freshwater ray-finned fish, a darter from the subfamily Etheostomatinae, part of the family Percidae, which also contains the perches, ruffes and pikeperches. It is found in eastern North America where it is found in slower moving and still waters.

<span class="mw-page-title-main">Swamp darter</span> Species of fish

The swamp darter is a species of freshwater ray-finned fish, a darter from the subfamily Etheostomatinae, part of the family Percidae, which also contains the perches, ruffes and pikeperches. It is endemic to the Eastern United States.

<span class="mw-page-title-main">Blueside darter</span> Species of fish

The blueside darter is usually found in the Tennessee River drainage in Tennessee, Alabama, North Carolina, and Virginia, and less commonly found in Bear Creek, Shoal Creek, and Barren Fork.

The stripetail darter is a species of freshwater ray-finned fish, a darter from the subfamily Etheostomatinae, part of the family Percidae, which also contains the perches, ruffes and pikeperches. It is endemic to the eastern United States. It is found in small rivers and streams in the states of Tennessee, Ohio, Kentucky, Illinois, Alabama, Georgia, and Mississippi. Males are a golden-orange color with black barring on the fins, and grow to a length of about 2.8 in (7 cm). This fish feeds on midge larvae and other small invertebrates. It breeds in the spring; eggs are attached to the substrate, often under slab rocks, where they are guarded by the male. The population trend of this fish seems to be stable and it is a common species with numerous sub-populations over a wide range, and the International Union for Conservation of Nature has assessed its conservation status as being of "least concern".

The goldstripe darter is a species of freshwater ray-finned fish, a darter from the subfamily Etheostomatinae, part of the family Percidae, which also contains the perches, ruffes and pikeperches. It is endemic to the southeastern United States where it is found in Gulf Slope streams from the Colorado River drainage in Texas to the Flint River in Georgia, the Atlantic Slope in Ocmulgee River system, Georgia, and the Mississippi embayment north as far as southeastern Missouri and western Kentucky. It is typically found in small springs, streams, and creeks with aquatic and marginal vegetation and detritus. The female spawns on multiple occasions between about mid-March and June, sticking the adhesive eggs to plants, gravel and the sides of rocks. The goldstripe darter is a common species with a wide range and numerous sub-populations, and the International Union for Conservation of Nature has assessed its conservation status as being of "least concern".

The cypress darter is a species of freshwater ray-finned fish, a darter from the subfamily Etheostomatinae, part of the family Percidae, which also contains the perches, ruffes and pikeperches. It is endemic to fresh waters of the central and eastern United States. Its range includes drainages from the Choctawhatchee River, Florida, to the San Jacinto River, Texas, as well as the Mississippi River basin from southern Illinois and eastern Oklahoma to the Gulf of Mexico. It inhabits vegetated margins of swamps and lakes, and backwater habitats during the summer, while in winter it moves to flooded riffles and backwater bayous. It feeds mostly on small crustaceans, as well as insects and their larvae. Spawning takes place during spring and summer, with clusters of up to three eggs being laid, often stuck to the surface of dead leaves. The cypress darter has a very wide range and its population trend seems to be stable. It is a common species with numerous sub-populations, and the International Union for Conservation of Nature has assessed its conservation status as being of "least concern".

The arrow darter is a species of freshwater ray-finned fish, a darter from the subfamily Etheostomatinae, part of the family Percidae, which also contains the perches, ruffes and pikeperches. It is found in parts of Kentucky and Tennessee, particularly in the Cumberland and Kentucky Rivers. These small fish are part of the perch family. They grow to be about 4.5 inches (11 cm) in length. Their opercle, breast, and cheek are all unscaled. They have a vertical black bar at the base of their caudal fin. Six to nine vertical banded bars run down the side of the fish. The dorsal side of the fish is olive green in color, and the ventral side is a yellow to white pattern. The first dorsal fin has a black base, followed by green color, and then a reddish-orange end. The second dorsal is clear with two rows of laterally lined orange spots. The caudal fin is clear and has two-three vertical lines of orange spots. The anal fin has a green base and then clear at the end. The breeding male has bright orange-red spots and breeding tubercles present on the scales.

<span class="mw-page-title-main">Tippecanoe darter</span> Species of fish

The Tippecanoe darter is a species of freshwater ray-finned fish, a darter from the subfamily Etheostomatinae, part of the family Percidae, which also contains the perches, ruffes and pikeperches. It is endemic to the eastern United States.

<i>Etheostoma zonale</i> Species of fish

Etheostoma zonale, the banded darter, is a species of freshwater ray-finned fish, a darter from the subfamily Etheostomatinae, part of the family Percidae, which also contains the perches, ruffes and pikeperches. It is endemic to the eastern United States.

<span class="mw-page-title-main">Blackbanded darter</span> Species of fish

The blackbanded darter is a species of freshwater ray-finned fish, a darter from the subfamily Etheostomatinae, part of the family Percidae, which also contains the perches, ruffes and pikeperches. It is native to the river systems of the southeastern United States where it is found in the states of Tennessee, Georgia, Florida, Mississippi, Alabama, and Louisiana. It lives over sandy or gravelly bottoms in smaller rivers and streams and its color varies depending on the different habitats in which it lives. It feeds on small insect larvae and is itself preyed on by larger fish. It spawns between February and June depending on locality. It is generally a common fish throughout most of its range.

<span class="mw-page-title-main">Redfin darter</span> Species of fish

The redfin darter is a species of freshwater ray-finned fish, a darter from the subfamily Etheostomatinae, part of the family Percidae, which also contains the perches, ruffes and pikeperches. It is native to the south-central United States, where it occurs in Missouri, Arkansas, Kansas, and eastern Oklahoma.

The lipstick darter is a species of freshwater ray-finned fish, a darter from the subfamily Etheostomatinae, part of the family Percidae, which also contains the perches, ruffes and pikeperches. It is endemic to the eastern United States, where it occurs in the Tallapoosa River drainage above the Fall Line in Alabama and Georgia. It inhabits rocky riffles of creeks and small to medium rivers.

References

  1. ↑ NatureServe (2013). "Etheostoma microperca". IUCN Red List of Threatened Species . 2013: e.T202504A2745380. doi: 10.2305/IUCN.UK.2013-1.RLTS.T202504A2745380.en . Retrieved 19 November 2021.
  2. 1 2 "Etheostoma microperca(least darter)" . Retrieved 3 May 2012.
  3. 1 2 "ODNR Division of Wildlife". Ohio Department of Natural Resources . Retrieved May 3, 2012.
  4. 1 2 Paine, M.D.; Dodson, J.J.; Power, G. (October 1982). "Habitat and food resource partitioning among four species of darters (Percidae: Etheostoma) in a southern Ontario stream". Can. J. Zool. 60: 1635–1641. doi:10.1139/z82-214.
  5. ↑ "Etheostoma microperca". Minnesota Department of Natural Resources. Retrieved 26 April 2012.
  6. ↑ The life history of the least darter, Etheostoma microperca, in the Iroquois River, Illinois. Urbana, Ill. : State of Illinois, Illinois Institute of Natural Resources, Natural History Survey Division, Illinois Natural History Survey. 1979.
  7. 1 2 "Least Darter" . Retrieved 3 May 2012.
  8. ↑ Petravicz, J. J. (1936). "The breeding habits of the Least Darter, Microperca punctulata Putnam". Copeia. 2: 77–82. doi:10.2307/1436646.
  9. ↑ "Species profile". Minnesota Department of Natural Resources . Retrieved May 3, 2012.
  10. ↑ Burr, Brooks M.; Page, Lawrence M. "The life history of the least darter, Etheostoma microperca, in the Iroquois River, Illinois". ideals.illinois.edu. Retrieved May 3, 2012.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.