/ c,_ ti.-- FISHERIES RESEARCH BOARD OE cumg NANAIMO, B. FISHERIES RESEARCH BOARD CE CANADA r Translation Series No. 533 Migration of the iSurumet squid, Ommastrephes sloani pacificus (Steenstrup), ------ in -the -coastal waters of Japan By Junsuke Soeda From: Scientific Papers of the Hokkaido Experimental Fisheries Institute No. 4, pp. 1-30, 1950. - Translated by*Expme-s,s-Ttanslatian_Service-,_ -4-01- +Il e Bureau for Translations, Foreign Language Division, Department of the Secretary of State of Canada Fisheries Research Board of Canada Biological Station, Nanaimo, B. C. 1965 GP/5 44 DEPARTMENT OF THE SECRETARY OF STATE SECRÉTARIAT D'ÉTAT BUREAU FOR TRANSLATIONS BUREAU DES TRADUCTIONS FOREIGN LANGUAGES DIVISION DES LANGUES DIVISION ÉTRANGÈRES TRANSLATED FROM - TRADUCTION DE INTO - JAPANESE ENGLISH SUBJECT - SUJET MIGRATION OF THE SQUID ISUR1flME 1 AUTHOR - AUTEUR SOEDA, JUNSUKE TITLE IN ENGLISH - TITRE ANGLAIS MIGRATION OF TEE (SiTUI-4-11SURUIel) CeLASTREPHES SLOAN' PACIFICUS (STEENSTRUP) IN THE COASTAL WATERS OF •,fAPAN TITLE IN FoREIGN LANGUAGE - TITRE EN LANGUE ETRANGERE Ommastrephes sloani pacificus (STEENSTRUP) ;5:e1-. tàs REFERENCE - RgFdREN,CE (NAME OF BOOK OR PUBLICATION - NOM DU LIVRE OU PUBLICATION) , )% CAZ-1/4:C eUgg.Irjtjr--( Wre tu-4> _,GM-T-ME EXPERIMENTAL FISHERIES INSTITUTE ) No.4, 'Mtn-CH-1-9,C /--3 û /Îrà • PUBLISHER - éDITEUR EXPERIMENTAL FISHERIES INS' TITUTE OF HOKKAIDO CITY - VILLE DATE PAGES 1950 1 - 23 Mr. G e A. Mendel, Chief REQuEST RECEIVED FROM Foreign Languages Division OUR NUMBER REQUIS PAR NOTRE DOSSIER N ° 5506 Express DEPARTMENT Dept. of Fisheries TRANSLAToR Translation MINISTÉRE TRADUCTEUR Service YOUR NumBER DATE CoMPLETED 27th Jan. 165 VOTRE DOSSIER NO 769-18-14 REMPLIE LE DATE RECEIVED REÇU LE 7th December 1964 50 $-200-10- "e6' MIGRATION OF THE SQUID ISURUMEt, OMMASTREPHES SLOANI PACIFICUS (STEENSTRUP) IN THE COASTAL WATERS OF JAPAN JUNSUKE SOEDA Report from the Experimental Fisheries Institute of Hokkaido, No. 4 March 1950 Experimental Fisheries Institute of Hokkaido 4 OF THE Sun MIGRATION , SURUMEI OLTIASTREPIIES SLOANI P.1 PACIFICUS (STEENSTRUP), IN THE COASTAL WATERS OF jApAN Junsuke Soeda INTRODUCTION The squid, Surume, Ommastrephes sloani pacificus, is very common and is found in all coastal waters of Japan, although there are some seasonal variations in its distribution. From the point of view of the quantity fished, it is one of the most important natural resources of the sea in Japan. In Hokkaido, especially, larger quantities of squid are caught than of any other sea product, about 60% of the total catch being made in South Hokkaido. Hence the economy of the South Hokkaido region depends to a large extent on the fishing of squid. From 1910 onwards, the fishing of squid can be divided into three periods with respect to the quantity caught in Hokkaido. The first period lasted until the early Taisho era. The boats used had no engine, and the fishing was carried out when the boats were at anchor. This period, therefore, may be described as the rowing boat period. The second period lasted until about 1935. Some engine- powered boats were now used; the fishing was still carried out at anchor, but the fishing area was considerably increased. The third period began in 1935 and reaches up to the present time. No advances or changes in the types of fishing boats have been made, but the number of engine-powered boats has greatly grown. The boats are not anchored, and the fishing position is changed continuously so that the fishing area has increased still further. The quantity fished annually during these three periods increased from about 18,750 to 37,500 tons in the first period, 2 to about 56,000 tons in the second period and to about 94,000 tons in the third period. There were however considerable differences in every period, depending on the year (see Fig. 1). An investigation into the causes of the fluctuations in the annual quantities fished is required, so that fluctuations can be predicted and thus help to stabilise the squid fishing industry. In the case of the squid, however, there is no method airailable at present for investigating their group formation and age distributior„ which are known in the cases of other fish. Hence fundamental eco- logical studies must be undertaken, and any investigations should • be based on the results of such ecological studies. Complete ecolo- gical studies of one species cannot however be carried out in a short period. Studies of this kind are now in progress, but parallel investigations of the migration routes, which are directly related to the fishing, are also needed. D.2 .••■■ ,• Fig. 1: Annual total catch in Hokkaido (kan) (1 kan - 3.75 kg.) 3 History of the investigetions of migration The Hokkaido Fisheries Institute made an investigation in 1889 of the directions from which the squid came every season. According to their records, along the Pacific coast of South Hokkaido the squid travel from shallow water to deep water, in the Tsugaru Channel the squid come from the west and move to the east, in the Hinokiyama district the squid come from the south-east and travel to the west, and in the Goshi district they come from the South and travel to the north. According to an investigation carried out by the Ministry of Agriculture and Commerce in 1912, squid arrive in Sado Island the from the Noto coast and then P.3 gradually move further out from the shore at the beginning of winter. Sasaki (1921) has published a report on the differences in the fishing season in various parts of the coastal waters of the Japan Sea, but failed to find any evidence that the squid migrate all the way from Kyushu to Hokkaido. He did not reach a conclusion on the problem of the Surume species, i.e. whethar all the Surume-squid in the coastal waters of Japan belong to the same species or not e and after comparing the development and the rate of maturing of the reproductive organs of squid found in Hokkaido with those of the squid found in Kyushu he concluded that it was improbable that the squid would travel such a great distance. Ishii (1932) has reported, from the results of ecological investi» gations carried out at Oki Island in Shimane prefecture, that there are two different species of squid. Isahaya and Kawana carried out investigations on the squid in Hokkaido and North East Japan over a period of 6 years (1927 - 1932), and classified the Surume- squid found in the Japan Sea into two main types, the Northern type and the Southern type, which they classified further into sub- groups, as shown in Table 1. They also reported (1932) that the Surume-squid generally travel in a north-westerly direction. 4 Table 1: The classification due to Isahaya, and the distribution North Distribution -district Pacific east of the Hidaka and Pacific Group: Uraga Coasts. species South Distribution - the Iwate Northern Pacific prefecture Group: coasts Type Japan SeaSe Distribution - around Esashi Surume- species : and Hakodate, and as far as -{ East Muroran Squid Southern Pacific Distribution - district south of species : the Iwate prefecture coasts Type Japan SeeSea Distribution - districts further species : south than Rishiri and Rebun I Islands Tauchi and Sanyoshi (1940) have suggested, from a consideration of the relationship between the fishing season and locality, differences in the annual catch, etc., that there are two different groups of squid, one of which travels long distances, like the common sardine Sardina Melanosticta (T. et S.), while the other group stays within a local area. The present author (1945) has discussed the possibility of predicting the annual fishing conditions for the Surume-squid and has described briefly the two types suggested by Ishii and Isahaya and the relationship between the distribution and fishing season. After considering the changes in sea temperature, the feeding habits of the squid, their change in size (mantle length) and the seasonal changes in the fishing grounds, obtained from the results of inves- tigations at fishing grounds where the statistics of the amount caught the previous year were known, thp present author reported (1946) that the Surume-squid in the coastal waters of Japan all belong to a single species which travel between Saharein (Karafuto) in the North and Kyushu in the South. In order to prove this, marking and releasing tests were carried out in the autumn of the same year in the Tsugaru Strait. Some of the results were published 5 in Part 1 (1947) and additional results have been reported since. The results obtained to date (1948) are summarised in this report. The Movement of the Fishing Season and the Change in Mantle Length The Surume-squid can be caught anywhere along the coasts of Japan, both on the Japan Sea coasts and the Pacific coasts. The most important fishing grounds are, however, the coasts along which the Tsushima Current flows, and the Tsugaru Strait. According to Sasaki (1921), who has described squid fishing in the Japan Sea, the fishing season commences at Uryo Island in early spring and after ten days or so the first catches are made at Oki Island; about 2 weeks after this fishing begins on the north-west coast of the Noto Peninsula. The fishing season at the Noto Peninsula com- mences in early May and by the middle of the month fishing begins on the west coast of Sado Island, and, at the end of the month, on the east coast of the island. The fishing season in the Tsugaru Strait begins a few days later. The change in mantle length of the squid caught at many p.4 'places during their fishing season is described.