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The goldline darter (''Percina aurolineata'') 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. ==References== * Gimenez Dixon, M. 1996. (''Percina aurolineata'' ). (2011 IUCN Red List of Threatened Species. ) Downloaded on 2 September 2011. * * 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Goldline darter」の詳細全文を読む スポンサード リンク
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