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ANADIAN TRANSLATION OF FISHERIES AND AQUATIC SCIENCES No. 4914 1•113.MRY ItiND• OCE nIt5LIOrTistQ• UE " „ •, Fuf oethISS pl.7.(1n'b Report of an ecological survey of the Steller sea lion in Hokkaido by T. Itoo, H. Katoh, K. Wada, K. Shimazaki, and K. Arai Original Title: Hokkaido ni okeru todo no seitai chosa hohoku From: Geiken tsushin, January (305/6): 1-18, 1977 Translated by the Translation Bureau Multilingual Services Division Department of the Secretary of State of Canada Department of Fisheries and Oceans Pacific Biological Station Nanaimo, B.C. 1983 60 pages typescript Secretary Secrétariat of State d'État MULTILINGUAL SERVICES DIVISION — DIVISION DES SERVICES MULTILINGUES TRANSLATION BUREAU BUREAU DES TRADUCTIONS LIBRARY IDENTIFICATION — FICHE SIGNALÉTIQUE c rriti-s 4/1/-1 Translated from - Traduction de Into - En Japanese English Author - Auteur Tetsuro ITOO, Hidehiro KATOH, Kazuo WADA, Kenji SHIMAZAKI and Kazutoshi ARAI Title in English or French - Titre anglais ou français Report of an ecological survey of the Steller sea lion in Hokkaido Title in foreign language (Transliterate foreign characters) Titre en langue étrangère (Transcrire en caractères romains) Hokkaido ni okeru todo no seitai chosa hohoku Reference in foreign language (Name of book or publication) in full, transliterate foreign characters. Référence en langue étrangère (Nom du livre ou publication), au complet, transcrire en caractères romains. Geiken tsushin Reference in English or French - Référence en anglais ou français Whale research reports Publisher - Editeur Page Numbers in original DATE OF PUBLICATION Numéros des pages dans Japanese Whaling Society, Inc. DATE DE PUBLICATION l'original 1 - 18 Year Issue No. Volume Place of Publication Année Numéro Number of typed pages Lieu de publication Nombre de pages dactylographiées Etchujima 1-3-1, Koto ku, Tokyo, Japan 1977 Jan 305/6 60 1008910 Requesting Department Fisheries and Oceans Translation Bureau No. Ministère-Client Notre dossier no Sci Info and Pub J. W. C. // Ps Branch or Division Translation (Initials) Direction ou Division Traducteur (Initiales) Person requesting Dr M. Bigg Demandé par DEC - 198? Your Number Votre dossier no Date of Request August 19, 1982 Date de la demande SEC 5-111 (81/01) .4„ Smetary Secrétariat of State d'État Id MULTILINGUAL SERVICES DIVISION — DIVISION DES SERVICES MULTILINGUES TRANSLATION BUREAU BUREAUDESTRADUCTIONS Cl ients No.—No du client Department — Ministère Division/Branch — Division/Direction City — Vine Scientific Information Fisheries and Oceans and Publications Ottawa Bureau No.—No du bureau Language — Langue Tmmlator (Initials) — Traducteur (Initiales) Japanese J.W.C. 1008910 / ps DEC - 6 198e WHALE RESEARCH REPORTS No. 305 January 1977 Japanese Whaling Whale Research Tokyo, Kotoku, Society, Inc. Institute Etchujima 1 - 3 - 1 T 135 Tel Tokyo (642) 2888 pl Report of an ecological survey of the Steller sea lion 1 in Hokkaido . (I) 2 3 4 3 Tetsuro ITO° , Hidehiro KATOH , Kazuo WADA , Kenji SHIMAZAKI 5 and Kazutoshi ARAI . Fc:r preheyi si ve_ 1. Part of a y study, "Biological research on the stocks of Pinnipedia" partly funded by the Ministry of Education (Research representative Prof. Masaji NISHIKAWA, Ryukyu University). 2. Gifu Dental College 3. Northern Sea Fisheries Research Institute, Faculty of Fisheries, Hokkaido University. 4. Primate Research Institute, Kyoto University. 5. Faculty of Fisheries, Hokkaido University. SEC 5-25 (Rev. 81/11) Canacrâ 2 The objectives of the survey Steller's sea lion, Eumetopias jubata (SCHREBER 1776) (1 Japanese "todo") has long been known to occur in the Sea of Japan. In addition to Allen (1880), Naumov (1933), Ognev (1935), Okada (1938), Matsuura (1943), Ellermann and Morrison-Scott (1951), there can be mentioned the more recent work of Nishiwaki (1972) and Geptner and Naumov (1976). Nishiwaki and Nagasaki (1960), Nishiwaki (1965) and Nishiwaki (1967) have given outlines of the migration, ecology and regional characteristicS of the herds which visit Hokkaido. Using specimens from various parts of Hokkaido, Itoo (1973) stated that three sea areas could be distinguished in which the herds of visiting sea lions were of differing age and sex compositions. However collections were not made along the whole coast, so this study was both limited and preliminary. There are also studies made some twenty years ago of the damage done by sea lions to the fishery, particularly by collecting the observations of people engaged in coastal fishing, but there have been absolutely no studies of sea lion ecology in Japan. According to Nishiwaki (1967) and Itoo (1973) it could be considered that the sea lions visited two sea areas, in north and south Hokkaido, with contrasting characteristics. The objective of the survey was to clarify many basic points about the ecology of the sea lions such as the seasons at which they appear and disappear, their distribution,their haul-out areas, the composition of the migrating herds, the size of the herds and their feeding. Also included in the planning were studies of the growth, sexual maturity, breeding, comparative morphology and parasites of captured specimens. 3 During the course of the survey many people gave us assistance. We wish to express and record our gratitude to the following persons. In the survey in Northern Hokkaido:- Mr Shigeo OISHI (Rebun town, Funadomari) Mr Yasuo OISHI (Rebun town, Funadomari) Mr Hirota SAKANO (Rebun town, Funadomari) Mr Binichi KURI (Rebun municipal offices) Mr Jusuke OTSUKA (Rebun municipal offices) Mr Takaji FUJIMOTO (Sarafutsu village, Hamaonishibetsu) Mr Mitsutaka KURASHINA (Keio University) In the survey in Southern Hokkaido:- Mr Yoshietsu ARASHIDA (Usushiri Fisheries Experimental Station, Faculty of Fisheries, Hokkaido University) Mr Kiyoshi NOMURA (Usushiri Fisheries Experimental Station Faculty of Fisheries, Hokkaido University) and also all the hunters from Minamikayabe town, Birodomari, especially Mr Ryoji KAMATA and everyone at the Northern Sea Fisheries Research Institute of the Faculty of Fisheries of Hokkaido University. The methods of the survey The Northeill Hokkaido survey, which centre3around the north shore of Rebun Island (Rebun town, Funadomari) was made in two periods, from 21 December 1975 to 13 January 1976 and from 27 February to 10 March 1976. The Southern Hokkaido survey was made in the southwest part of Funka Bay (Minamikayabe town) from 28 February 1976 to 22 March 1976. (Figure 1) * Funka Bay is shown on many maps as Ushiura Bay. Translator. :17) • • .•: • T R ESR1FIA i* «REF N . 4- HI MAS11111A REE F FUNKA IA? ,Z:31000 - ,tstANI • CAPE e lIKO.T1111 SR1RA SE B IRQUIMA RI FIINA »MAU BA y UE11.11F1 ik.** Wt.% NA Ke. 6 ilokm 13 AMIN MALI lkm Figure 1 The survey areas and the places where sea lions were captured. The * shows the places of capture, the numbers in brackets shows the number captured. • Cooperation was obtained in both areas from the persons locally concerned with sea lion destruction operations. In Northern Hokkaido six trips were made with Mr Yasuo OISHI in his Kojumaru No. 5 - (1.5 tons) to observe the number of individuals, the size composition and movements of sea lions on the reefs and at sea. Following Scheffer (1967) and Allen (1880) the measurements made on the eleven individuals captured included the body length and thirteen other measurements and there were also thirteen measurements of the size and weight of the internal organs, including the gonads. The skulls and the whole skeletons were preserved as dry specimens and the gonads, the exterior and interior parasites were preserved as specimens hardened in 10% formalin. The age was assessed principally from the annual ring structure of the cementum layer and the dentine layer of No. 3 incisor in the upper 10,45 jaw . The stomach contents were investigated after hardening in 20% formalin. Through the good offices of Mr Yasuo OISHI it was also possible to obtain as specimens nineteen skulls captured before and after the survey periods. The teeth and tusks of an individual captured in February 1976 were received from Mr Kiyoshi ARASHIDA, and these twenty individuals were included as specimens for age determination. Reference was made to the capture records (1973 to 1975) in the Rebun town municipal offices to ascertain the numbers captured in recent years. Sea lion hunters and others in the fisheries business were interviewed about sea lion ecology. 6 Results and discussion Because the number of specimens is extremely small, analyses and discussions of the habits and movements of the sea lions, their exterior morphology and of the data related to the weight of their interior organs, gonads and skulls are omitted from the present report. Studies of the exterior and interior parasites and information obtained about pinnipedia other than sea lions are to be presented in separate reports. 1. Report of observations (Rebun) Number of individuals on land On trips with Mr OISHI and with local sea lion hunters, observations were made of sea lions on land on Hirashima reef about 600 m north of Todo Island, offshore from the northwest of Rebun Island, and the numbers were counted with binoculars (Nikon 9x35). The dates of observations and the numbers of individuals were as follows:- 12 December 1975 30 - 40 28 December 1975 30 - 40 30 December 1975 71 2 January 1976 1 The reefs were assigned numbers by the authors (see Figure 2). Observations were made on 30 December without being noticed by the sea lions for about 15 minutes after 6.35 a.m. from the point on land marked "0" on reef No. 4 (R - 4). The herds were resting on land and the largest total a L: a oiist- ance oF number observed on the southern side of reef No. 2 s/ (R - 2 , local name "uchinoshima" -"middle island") and on the southern side of reef No. 1, at .1 àieLarice. of go vyt (R 1, "okinoshima" - "outer island") was 71. • 7 •■■■ Hm Figure 2 The Hirashima reefs on the north coast of Rebun Island.