Channa maculata (Lacepède 1801)

This taxon is one of a number of benthopelagic species in the Yangtze River system. Benthopelagic fish inhabit the water column niche immediately above the bottom, feeding on benthos and zooplankton. The upper Yangtze basin consists chiefly of Paleozoic limestone and terrigenous sedimentary rock, with some granitic material. The most downstream element of the upper Yangtze basin is often termed the Sichuan Basin; here the Yangtze cuts through Triassic and Permian material before entering the Three Gorges. The Three Gorges area is a stretch of the Yangtze that runs approximately 660 kilometers, terminating at the site of the Three Gorges Dam. Prior to construction of the dam, the Three Gorges area was a site of exceptional natural beauty; after dam construction the gorge areas were filled with approximately 100 meters in depth of Yangtze water, and considerable amounts of the watershed were graded. The lower Yangtze basin consists of anabranching river structures and Pleistocene coastal terraces. Prior to development of the Three Gorges Dam, the Yangtze Delta was replenished with a copious sediment load reaching the river mouth; however, the dam has now severely limited the natural flow and deposition of sediment to the delta region. Consequently, the integrity of the delta is been compromised, with scouring exceeding deposition, and the very stability of the delta is endangered. Lower and middle basins of the Yangtze carry heavy pollutant loads. In the lower Yangtze basin nitrate levels are high, measuring at about 1000 tons per day at Datong; these levels accrue from high applications of chemical fertilizer applied and also considerable loadings of untreated sewage due to the large human population of the basin, with correspondingly little infrastructure for sewage treatment. Heavy metal concentrations are also high in the lower Yangtze, with measurements of dissolved lead at 0.078 microgram/liter; cadmium (0.024 microgram/liter), chromium (0.57 microgram/liter), copper (1.9 microgram/liter), and nickel (0.50 microgram/liter). Levels of dissolved arsenic have been measured at 3.3 microgram/liter) and zinc at 1.5 microgram/liter), both notably higher by factors of 5.5 and 2.5 respectively than other typical large world rivers. In Yangtze River suspended sediment, arsenic comprises 31 microgram/gram, lead comprises 83 microgram/gram, and nickel comprises 52 micrograms/gram of sediment content A number of other benthopelagic associates are found in the Yangtze, including: Anabarilius polylepis, Bangana rendahli, Pseudogyrinocheilus prochilus, Sinocyclocheilus grahami and Siniperca roulei. The demersal fish Silurus meridionalis also is found as a Yangtze River endemic species.

Distinct pairing during breeding in shallow freshwater areas amid plants (Ref. 205). Oviparous (Ref. 205).

Inhabits silty and weedy bottoms of rivers and ponds or lakes (Ref. 9671). Feeds on crustaceans, large insects, frogs and fishes (Ref. 5258). Recorded as having been or being farmed in rice fields (Ref. 119549).

Adults inhabit silty and weedy bottoms of rivers and ponds or lakes (Ref. 9671). Feed on crustaceans, large insects, frogs and fishes (Ref. 5258). Oviparous (Ref. 205). Recorded as having been or being farmed in rice fields (Ref. 119549).

fisheries: commercial; aquaculture: commercial

分布於中國大陸、日本、台灣及菲律賓等。台灣分布於西部河川中、下游、池塘與溝渠等。已能人工養殖，主要以南部為主。

常見的食用魚類，也是手術後進補的聖品，現在已經可以人工養殖。不過野生的七星鱧在棲地被破壞及外來種的競爭下，已經較少見。

體延長而呈棒狀，尾部側扁。 頭較大，頭頂平，前部略平扁。口大，端位，下頷略突出，口斜裂；上頜末端達眼睛後緣直下方；上下頜均有銳利牙齒。頭部及體部均被有大小一致之圓鱗；側線平直，在臀鰭起點上方中斷，向下1行或2行鱗片，再沿體側中央向後直走，側線鱗為50-56。背鰭單一，僅具軟條38-45；具腹鰭，但小型；尾鰭圓形。體灰黑色，腹部灰色；體側有不規則的大型黑斑二行，尾鰭基部前後有黑白交錯之橫紋，在幼魚時更明顯。

棲息於河流、池塘與溝渠等水生植物雜生和淤泥底質的靜水域或緩流處。能在缺氧或淤泥中生活。常藏身於水草或水底襲擊小魚及其他水生動物。成魚會築巢及具護幼習性。

The blotched snakehead (Channa maculata) is a species of snakehead. It is one of four species of the genus Channa native to China. It is also to native northern Vietnam and Taiwan, but has been widely introduced to other countries, where it is an invasive species. This predatory species typically grows to a length of 20–30 cm (7.9–11.8 in), but it has been confirmed at 33 cm (13 in) and some suggest it may reach a far larger size.