Japan. J. Ichthyol. 魚 類 学 雑 誌 41(3): 317-321, 1994 41(3): 317-321, 1 9 9 4

Description A Record of a Great Siberian , Measurements and counts are shown in Table 1. dauricus, off Niigata, Sea of Japan The fish, with 5 rows of unique scutes and 2 pairs of (: Acipenseridae) long barbels attached to the undersurface of the snout, had a heterocercal caudal fin and a strongly Yoshiharu Honma1 and Hideyoshi Itano2 curved (semicircular), ventrally positioned mouth, 1Faculty of Science, Niigata University , reminiscent of sharks. The left and right gill (operc- 2-8050 Ikarashi, Niigata 950-21, Japan ular) membranes were free from the isthmus and 2Niigata Prefectural FisheriesExperimental Station , broadly connected with each other. As the opercu- 3-13098-8 Ikarashi, Niigata 950-21, Japan lum does not cover perfectly the branchial cavity, gill filaments are visible without difficulty by the naked (ReceivedJune 27, 1994; in revisedform September10, 1994;accepted September 14, 1994) eye (Fig. 2). The ventral fins were situated postero- ventrally near the cloaca, the latter being somewhat closer to the ventral fin bases than the anal fin origin. In recent years, the occurrence of , The color when fresh was dark grayish-green dor- family Acipenseridae, has become less common wor- sally and white ventrally. All scutes and the anterior ldwide. With regard to Japanese waters, Honma margin of the pectoral fins were white. (1988), who compiled records and distributional notes on sturgeons along the coast of the Japanese Discussion archipelago, noted that sturgeons had not been rep- orted since 1980. He especially noticed the bio- Amaoka and Nakaya (1975) reported 4 individu- geographical significance of two comparatively als of Huso dauricus from waters around Hokkaido, recent records: the first of a great Siberian sturgeon, one, which was caught by gill net 2 miles off Oshoro Huso dauricus, from the coast of Hokkaido Bay in February 1975, being the first record from the (Amaoka and Nakaya, 1975) and a record of a green Sea of Japan. Since only 5 individuals have been sturgeon, mediostris, in the Sea of Japan off documented from the north-eastern waters of Japan, Aomori Prefecture, on 19 May, 1979 (Shiogaki, it is very likely that the present specimen marks not 1982). Further, Shiogaki (1990) reported briefly on only the southern extreme of the species distribution a great Siberian sturgeon caught in a gill net for in the Sea of Japan, but also for the Japanese archi- salmon off the coast of Wakinosawa, Mutsu Bay, pelago. Aomori Prefecture, the most northern part of Miyadi (1940) illustrated H. dauricus from the Honshu Island, on 26 January, 1989. Songhua River, and mentioned further localities, viz. The present short paper dealts with a recent record the Amur River, Ussuri River and Lake Khanka. of a great Siberian sturgeon caught from the coast of Mori (1936) and Berg (1948/1962) also noted these Niigata, Sea of Japan. localities, emphasizing the Amur Basin. Sato (1942) listed the species from Sakhalin Island, and Kostarev and Turnin (1970) obtained several immature speci- Material mens from the coast of the Okhotsk Sea. Previously, On 17 April, 1994, a medium-sized sturgeon was Soldatov and Lindberg (1930), Taranetz (1937), caught by a motor trawler, fishing for olive flounder, Schmidt (1950), Andriashev (1954) and Lindberg Paralichthys olivaceus, 6.4km off Neya Village, San- and Legeza (1965) had no records documented from poku Town, northern part of Niigata Prefecture, the Okhotsk Sea. central west Honshu Island (Fig. 1). After exhibi- Regarding the present specimen, considered to be tion at a fish festival (early May) at that fishing immature male (subadult), it seems probable that village, the frozen specimen was kindly presented immature great Siberian sturgeon migrate in coastal through the courtesy of the fisherman, Mr. Z. waters of the northern part of the Sea of Japan and Tamura, to Niigata Prefectural Fisheries Experimen- western Okhotsk Sea, before entering Russian Far tal Station. East rivers for spawning (Berg, 1948/1962; Kostarev

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Fig. 1. Map of Niigata Prefecture, Sea of Japan, showing the collection site (arrowhead) of a great Siberian sturgeon, kaluga, Huso dauricus. Other known localities in Japanese Islands: 1-Sarufutsu, 2-Oshoro, 3 Minami-kayabe, 4-Wakinosawa, 5-Sanriku.

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Fig. 2. Side (top) and ventral (below) views of a great Siberian sturgeon, Huso dauricus (1619mm in fork length), caught by motor trawler, off the coast of Sanpoku Town, Niigata Prefecture, Sea of Japan. Note rows of scutes, 2 pairs of barbels, strongly curved mouth and gill membranes free from the isthmus.

and Turnin, 1970). It is also likely that very few addition, a further undetermined specimen reported individuals move into the middle regions of the Sea by Saito et al. (1958) from off the coast of Kakizaki, of Japan, such as Niigata, via the coast of southern near Naoetsu, might have been A. multiscutatus. Hokkaido and northern Honshu. Although the identity of the latter specimens is dou- For the records of sturgeons in Niigata district, btful (Nakabo, 1993), it appears that two sturgeon subsequent to Tanaka's original description of Acipe- species belonging to different genera, Acipenser and nser multiscutatus and further notes (1908, 1933, Huso, have been collected from the Niigata region. 1936), Honma (1952, 1988, 1992) tentatively added As was mentioned above, their migration routes may this species to his ichthyofaunal list of Niigata Pre- have followed the west coast of Sakhalin Island, fecture. The specimen in question was caught off Hokkaido and northern Honshu in the cold water Naoetsu, southernpart of Niigata Prefecture. In condition.

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Table 1. Measurements and counts of the present specimen of a male Huso dauricus

Acknowledgments found in Niigata Prefecture. Niigata NippO-sha, Niigata. 358pp. (In Japanese.) The referee kindly informed us a record of Huso Kostarev, B.L. and B.V. Turnin. 1970. Huso sturgeon in dauricus caught by the set net from the coast of waters of the northwestern part of Okhotsk Sea. Bull. Sanriku-chou, Iwate Prefecture, Northeastern Dis- Pacif. Sci. Inst. Fish. Oceanol., 74: 346-347. trict of Honshu, the Pacific side, on 20 May, 1984. Lindberg, G.U. and M.I. Legeza. 1965. Fishes of the Sea of Japan and adjacent area of the Sea of Okhotsk and the Yellow Sea. II. Teleostomi: XII. - Literature Cited XXVIII. Polynemiformes. Acad. Nauk., Moscow- Amaoka, K. and K. Nakaya. 1975. First record of kaluga Leningrad. 391pp. sturgeon, Huso dauricus, from Japan. Japan. J. Ich- Miyadi, D. 1940. Freshwater fishes of Manchoukuo. Pages thyol., 22: 164-166. 22-88 in T. Kawamura, ed. Report of the limnobiolog- Andriashev, A.P. 1954. Fishes of the northern seas of the ical survey of Kwantung and Manchoukuo. USSR. Acad. Nauk., Moscow. 566 pp. (In Russian.) Mori, T. 1936. Studies on the geographical distribution of Berg, L.S. 1948/1962. Freshwater fishes of the USSR freshwater fishes in Eastern Asia. Toppan Print, Tokyo. and adjacent countries. Vol.1. Acad. Nauk., Jerusalem. 88pp. 504pp. (English version by Israel.) Nakabo, T. (ed.). 1993. Fishes of Japan with pictorial keys Honma, Y. 1952. A list of the fishes collected in the to the species. Tokyo. 1474pp. (In Japanese.) Province of Echigo, including Sado Island. Japan. J. Saito, Y., C. Miyamoto and K. Takahashi. 1958. A stur- Ichthyol., 2: 138-145, 220-229. (In Japanese with Eng- geon caught in Kakizaki, Province of Echigo. Collect. lsih summary.) Breed., 20: 123-124. (In Japanese.) Honma, Y. 1988. Records and distributional notes on the Sato, S. 1942. A check list of the fresh water fishes of sturgeons along the coast of Japanese archipelago. Bull. Saghalien Island. Trans. Sapporo Nat. Hist., 17: 102 Biogeogr. Soc. Japan, 43: 51-55. (In Japanese with Eng- 112. lishsummary.) Schmidt, P.U. 1950. Fishes of the Okhotsk Sea. Acad. Honma, Y. 1992. Colored illustrations of marine fishes Nauk., Moscow-Leningrad. 370pp. (In Russian.)

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Shiogaki, M. 1982. A catalogue of the fishes collected from of Soviet Far East and adjacent waters. Acad.Nauk., the waters of Aomori Prefecture, Japan. Bull. Fish. Exp. Vladivostok. 200pp. (In Russian.) Stat., Aomori Pref., 1-36. (In Japanese.) Shiogaki, M. 1990. Rare and remarkable fishes recently collected from the coast of Aomori Prefecture. Letters 新 潟 県 山 北 町(日 本 海)か ら 得 ら れ た ダ ウ リ ア チ ョ ウ ザ from Aomori Pref. Aquacul. Cent., (51): 6. (In Japa- メ の 記 録 nese.) Soldatov, V.K. and G.U. Lindberg. 1930. A review of the 本 間 義 治 ・板 野 英 彬 fishes of the seas of Far East. Acad. Nauk., Vladivostok. 1994年4月17日 に,本 州 西 海岸,新 潟県 北 部 の山 北 町 寝 屋 沖 576 pp. (In Russian.) で ダ ウ リア チ ョウ ザ メ1尾 が 底 曵 網 に入 った.こ の標 本 は尾 叉 Tanaka, S. 1908. Notes on some Japanese fishes, with 長161.9cm,体 重32.56kgの 雄 亜 成 体 と思 わ れ,左 右 の鰓 膜 が 峡 descriptions of fourteen new species. J. Coll. Sci., Imp. 部 で 連 続 して,峡 部 か ら離 れ て い る こ と,口 が大 い に湾 曲 して 半 Univ. Tokyo, 23: 1-54. 月 形 を な して い る こ とで,容 易 に本 種 と同定 さ れ る.ま た,日 本 Tanaka, S. 1933. Fishes. Pages 74-352 in I. Amemiya, ed. 海 側 の南 限 の み な らず,本 種 分 布 の 南 限 の記 録 と して 注 目 され An illustration of useful, noxious and admiring aquatic る. and plants. Taichi-shoin, Tokyo. (In Japanese.) Tanaka, S. 1936. Fishes of Japan. Dainippon Tosho, (本 間:〒950-21新 潟 市 五 十 嵐2の 町8050新 潟 大 学 理 Tokyo. 334pp. (In Japanese.) 学 部;板 野:〒950-21新 潟 市 五 十 嵐3の 町13098-8新 Taranets, A.J. 1937. Handbook for identification of fishes 潟 県 水 産 試 験 場)

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