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Southeast Ecological Science Center
Channa maculata (Lacepde, 1802)
Reprinted with permission of Tokai University Press from Masuda, H., K. Amaoka, C. Araga, T. Uyeno, and T. Yoshino (eds.). 1984. The Fishes of the Japanese Archipelago. Tokai University Press, Tokyo, Japan.
Original description: Bostrychus maculatus Lacepede, 1801:140, 143. Histoire naturelle des poissons 3:i-lxvi + 1-558, pls. 1-34. Type locality: none designated. No type specimens.
Synonyms: Ophicephalus guentheri Sauvage and Dabry de Thiersant, 1874:4.
Common names: blotched snakehead. No other English names known; hei-yu (Tungting Lake, China; Nichols, 1943); tai wan li (Mandarin); le-hi (Taiwan; Shen and Tzeng, 1993); Taiwan-dojo (Japan and Taiwan; Uyeno and Arai, 1984; Hosoya, 2002); fibata (Madagascar; Paul V. Loiselle, personal commun., 2003).
Native range: southern China, south of the Chang Jiang (Yangtze) basin and Hainan (Nichols, 1943; Okada, 1960; Hay and Hodgkiss, 1981; Uyeno and Arai, 1984); northern Vietnam (Kotellat, 2001a).
Introduced range: Taiwan (established); introduced into Japan beginning in 1916 from Taiwan, established in Nara, Hyogo, Hiroshima, Mie, and Shiga prefectures, Japan, as of 1960 (Okada, 1960; Liang and others, 1962; Hay and Hodgkiss, 1981; Uyeno and Arai, 1984; Shen and Tzeng, 1993); Philippines (Uyeno and Arai, 1984), and Madagascar (misidentified as Channa striata; Raminosoa, 1987; Welcomme, 1988; Reinthal and Stiassny, 1991; Stiassny and Raminosoa, 1994; Lever, 1996; Lvque, 1998). Brind (1914) described a snakehead, Ophiocephalus marmoratus, from specimens supposedly acquired in Singapore and Malacca, Malaysia. “About 60 specimens, from 3 to 6 inches in length, were caught by a sailor of a merchant vessel and brought to New York direct” (Brind, 1914). There are no records of C. maculata having been introduced to either locality. The illustration that accompanied his description of this fish, although somewhat poor, appears to be of C. maculata and most certainly is not of any snakehead native to Singapore or Malaysia. Moreover, Brind (1914) commented that this fish “can stand cold water.” Therefore, we have included O. marmoratus as a synonym of C. maculata and conclude that either the localities from which these specimens were obtained were in error or that they were acquired from Chinese traders in those two cities. A somewhat similar situation involving a bagrid catfish, Hemibagrus elongatus, the holotype of which was supposedly from Singapore, was reported (Kottelat and others, 1998) where the actual type locality is believed to be China. Those authors also noted that although the type of H. elongatus might have come from Singapore, there had been active trade in Singapore of fishes imported from China for purposes of food, aquaculture or accidentally that would explain its Chinese origin. There are no type specimens of O. marmoratus.
This species may be one of the most widely introduced snakeheads in the Indian and Pacific Ocean basins. As of August 2002, it was becoming apparent that many reports of introductions and established populations of Channa striata in such places as Hawaii and Madagascar were based on misidentifications of C. maculata (Ralf Britz, personal commun., 2002). We have confirmed (October 2002) that the snakehead species recorded from Hawaii since the late 1800s is indeed C. maculata and not C. striata. See comments under Introduced range in the account for C. striata.
Channa maculata was introduced into Madagascar about 1978 by former President Didier Ratsiraka who had seen snakeheads at an aquaculture facility during an earlier visit to North Vietnam. The species he saw in North Korea was likely C. argus, but the species that was shipped to President Ratsiraka from China was C. maculata. The shipment was divided equally, one group stocked into ponds at the presidential summer residence near Antananarivo, adjacent to the headwaters of the Betsiboka River. The remaining fish were stocked into ponds at Ratsiraka’s home near Vatomandry on the east coast. Subsequent floods from monsoons washed snakeheads out of ponds in both localities and into adjacent natural waters. By 1986, C. maculata was well established in floodplain lakes of the Betsiboka basin. Nearly the same occurred on the east coast of Madagascar. There is an extensive canal system (Pangalanes Canal) that includes many inland lakes along the Indian Ocean coast of Madagascar that extends for hundreds of kilometers north to south. Snakeheads entered this canal system from ponds near Vatomandry and spread rapidly, being recorded about 200 km north of Vatomandry near Toamasina, the northern terminus of the Pangalanes Canal, several years later. It also dispersed southward to the Mangoro River. The species apparently was also moved to other areas of Madagascar by Sino-Malagasy merchants (Paul V. Loiselle, personal commun., 2003). It was initially misidentified as C. striata beginning with Raminosoa (1987). Reports of C. striata from Mauritius are also possible misidentifications of C. maculata.
Size: To 33 cm (Okada, 1960) but reaches a length of more than 1 m when fully mature (William S. Devick, personal commun. to Paul L. Shafland, 2002).
Habitat preference: Streams, lakes, ponds and ditches in southern China; prefers shallow waters with vegetation (Okada, 1960; Hay and Hodgkiss, 1981).
Temperature range: Native range is subtropical to warm temperate. Nevertheless, Okada (1960) reported that in Japan, this species tolerated “seven days in 7 oC air temperature out of water.” Atkinson (1977), however, cited it as a “tropical” species. Nevertheless, this snakehead has become established far north of its native range and assumed climate tolerances in Japan, following its introduction there.
Reproductive habits: Builds a circular, open nest in vegetation. Eggs float to surface and are guarded by parents. Spawns in Japan in early summer (Okada, 1960).
Feeding habits: Reported to feed on crustaceans, large insects, frogs, and fishes (Okada, 1960; Hay and Hodgkiss, 1981); described as a fierce predatory fish that “hides among rocks or aquatic plants until its prey approaches, then it quickly attacks, kills, and swallows its victim” (Hay and Hodgkiss, 1981).
Paul V. Loiselle (personal commun., 2003) reported that a fisherman in Madagascar had observed young blotched snakeheads slithering onto land, allowing their bodies to be covered by ants, then returning to the water where the ants floated at the surface and were devoured by the juvenile snakeheads. He also commented that amphibian populations in Madagascar are probably being negatively affected by the introduced blotched snakehead. Historically, frog tadpoles in the central highlands were preyed upon to some extent by native eels (Anguillidae), but now those same waters contain considerable numbers of Channa maculata.
Characters: No patch of scales on gular region. Head profile slightly depressed. Dorsal rays 40-46; anal rays 26-30. Lateral line scales 41-60 with lateral line continuous; transverse scales below lateral line 11; 9 scale rows between posterior rim of orbit to upper edge of operculum. Color pattern similar to that of Channa argus; dark stripe from tip of snout through orbit extending to almost above anterior base of pectoral fin; second dark stripe from posteroventral corner of orbit to posteroventral edge of operculum; sides of body with two rows of large, dark blotches extending posteriorly to anterior caudal peduncle; blotches in the form of two bar-like markings on caudal peduncle; dark markings toward mid-dorsal part of back extending up onto proximal part of dorsal fin. A key character for separating this species from C. argus are the bar-like markings on the caudal peduncle. In C. maculata, the most posterior dark bar (usually complete) is preceded and followed by pale bar-like areas, whereas in C. argus such pale markings are absent and the final dark marking is irregular, often blotch-like.
Commercial importance in the United States: Rarely mentioned on aquarist-oriented websites. Because it is a valuable food fish in southern China and Taiwan, we believed it could be available for sale in live-food fish markets. Ralf Britz (personal commun., 2002) confirmed that this species was one of the two snakeheads purchased from a live-food fish market in Boston, Massachusetts, in November 2001. A reexamination of the second specimen confirmed that it was also Channa maculata. We also noted from Federal records that imports of snakeheads from Guangdong Province, China, had increased during 2001. Because most culture of blotched snakeheads occurs in that province, the likelihood of availability of this northern snakehead “look-alike” in U.S. markets was increased. Ralf Britz (personal commun., 2002) also confirmed that the blotched snakehead has been present in Hawaii since before 1900, misidentified as C. striata, based on specimens in the U.S. National Museum of Natural History. We have learned that the species presently in culture in Hawaii as of 2002 is C. striata (Pam Fuller, personal commun., 2002), apparently imported in the early 1990s (Domingo Cravalho, Jr., personal commun., 2002).
Commercial importance in native range: Considered an important and valuable food fish in China (Nichols, 1943; Atkinson, 1977; Hay and Hodgkiss, 1981). It is the second most important snakehead species cultured in China with most culture activity located in Guangdong Province, southeastern China (Fang Fang, personal commun., 2002). Liang and others (1962) commented that it is only sold alive as a food fish within its introduced range in Taiwan.
Environmental concerns: This species is known to be a thrust predator feeding on large invertebrates and fishes. Moreover, its temperature tolerance indicates a species that could live in subtropical to temperate areas in the United States if introduced. That it is established throughout much of central Japan, an area located generally between 34-37o N, and its southernmost range in China is Hainan Island (about 19o N), is indicative of a species that has potential to establish from extreme southern Florida to North Carolina on the Atlantic Coast or central California on the Pacific Coast.
Comments: The diploid number of chromosomes of Channa maculata is 42 (Wu and others, 1986).
This species is also established on Oahu, Hawaii, and may prove to be a more widely introduced snakehead in the Indian and Pacific Ocean basins than previously known. See comments above and under Introduced range in the account for Channa striata.
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