Goldline darter
Encyclopedia
The goldline darter is a rare fish found primarily in the Cahaba River
in central Alabama
and the Coosa River
in Georgia
and Alabama. It has been federally listed as a threatened species since April 22, 1992.
The fish is between 1.6 and 2.9 inches long with brownish red and amber dorsolateral stripes. Unlike other members of the Hadropterus subgenus, its back is a pale to dusky color. It has a white belly on which a series of square lateral and dorsal blotches can be seen. These blotches are separated by a pale or gold-colored stripe.
This species prefers to live in areas with moderate to swift current and a water depth of over 2 feet in the main channels of free-flowing rivers. These areas where it is most common have a bottom of bedrock substrates, cobble
, or small boulders and contain patches of water willow or river weed.
There are two disjunct populations of goldline darters in the Alabama River Basin in addition to the population in the Mobile Basin. One of these groups occurs in the middle Cahaba River system, while the other is found in the Coosawattee River
system, which is a tributary of the Coosa River.
The goldline darter is threatened due to water quality degradation on the Cahaba River. Strip mining activities, urbanization
, and sewage pollution
have exterminated populations. The building of reservoirs has also led to the fragmentation and isolation of some populations of goldline darters. Attempts to raise the population of the goldline darter will focus on habitat preservation and water quality improvement. The main decrease in population density is in the Little Cahaba River population.
As in other Hadropterus subgenus members, the goldline darter spawns beginning in March and continues spawning through May or June.
Cahaba River
The Cahaba River is the longest free-flowing river in Alabama and is among the most scenic and biologically diverse rivers in the United States. The Cahaba River is a major tributary of the Alabama River and part of the larger Mobile River Basin...
in central Alabama
Alabama
Alabama is a state located in the southeastern region of the United States. It is bordered by Tennessee to the north, Georgia to the east, Florida and the Gulf of Mexico to the south, and Mississippi to the west. Alabama ranks 30th in total land area and ranks second in the size of its inland...
and the Coosa River
Coosa River
The Coosa River is a tributary of the Alabama River in the U.S. states of Alabama and Georgia. The river is about long altogether.The Coosa River is one of Alabama's most developed rivers...
in Georgia
Georgia (U.S. state)
Georgia is a state located in the southeastern United States. It was established in 1732, the last of the original Thirteen Colonies. The state is named after King George II of Great Britain. Georgia was the fourth state to ratify the United States Constitution, on January 2, 1788...
and Alabama. It has been federally listed as a threatened species since April 22, 1992.
The fish is between 1.6 and 2.9 inches long with brownish red and amber dorsolateral stripes. Unlike other members of the Hadropterus subgenus, its back is a pale to dusky color. It has a white belly on which a series of square lateral and dorsal blotches can be seen. These blotches are separated by a pale or gold-colored stripe.
This species prefers to live in areas with moderate to swift current and a water depth of over 2 feet in the main channels of free-flowing rivers. These areas where it is most common have a bottom of bedrock substrates, cobble
Cobble (geology)
A cobble is a clast of rock with a particle size of to based on the Krumbein phi scale of sedimentology. Cobbles are generally considered to be larger than pebbles and smaller than boulders . A rock made predominantly of cobbles is termed a conglomerate....
, or small boulders and contain patches of water willow or river weed.
There are two disjunct populations of goldline darters in the Alabama River Basin in addition to the population in the Mobile Basin. One of these groups occurs in the middle Cahaba River system, while the other is found in the Coosawattee River
Coosawattee River
The Coosawattee River is a river located in the northwest part of the U.S. state of Georgia.The river begins at the confluence of the Ellijay River and Cartecay River in the city of Ellijay in Gilmer County. The river flows west through the foothills of the north Georgia mountains.In Murray...
system, which is a tributary of the Coosa River.
The goldline darter is threatened due to water quality degradation on the Cahaba River. Strip mining activities, urbanization
Urbanization
Urbanization, urbanisation or urban drift is the physical growth of urban areas as a result of global change. The United Nations projected that half of the world's population would live in urban areas at the end of 2008....
, and sewage pollution
Pollution
Pollution is the introduction of contaminants into a natural environment that causes instability, disorder, harm or discomfort to the ecosystem i.e. physical systems or living organisms. Pollution can take the form of chemical substances or energy, such as noise, heat or light...
have exterminated populations. The building of reservoirs has also led to the fragmentation and isolation of some populations of goldline darters. Attempts to raise the population of the goldline darter will focus on habitat preservation and water quality improvement. The main decrease in population density is in the Little Cahaba River population.
As in other Hadropterus subgenus members, the goldline darter spawns beginning in March and continues spawning through May or June.