This article analyses inter-linkage among regimes related to regulation of and deliberates on the implications for Japanese policy in the future. International regulation of consists of not only the International Commission (IWC), but also the United Nations Convention on the Law of the Sea (UNCLOS), Convention on International Trade in Endangered Species of Wild Fauna and Flora CITES), and relevant regional regulatory regimes. This article shows that linkage between UNCLOS and IWC generated synergistic effect and further promoted another linkage between UNCLOS and North Atlantic Marine Mammal Commission (NAMMCO).
Based on the result of the analysis, the implications for diplomacy of the government of Japan were derived. Since the adoption of a moratorium on commercial in 1982, regulation of under IWC emphasized protection of whale stocks, rather than utilization of the resource. Japan argued that such situation of IWC goes against the objective of the International Convention for the Regulation of . On that ground, Japanese delegation states that withdrawal from the IWC is an option. However, even if Japan withdraws from the IWC, it will not mean that Japan can resume commercial at her own discretion.
In the case of withdrawal from IWC, how to fulfill the requirement of UNCLOS—to work through appropriate international organizations for conservation, management and study of cetaceans—will be a problem. Not only resumption of commercial , but also the continuation of scientific in will raise the same problem. An option for appropriate international organization would be Commission for the Conservation of Marine Living Resources (CCAMLR), although in-depth consideration of policy inter-linkage and compatibility between scientific activities under CCAMLR and scientific is necessary.

JEL classification: Q, Q28, R59

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In the present treatise the chief characteristics of the oceanographical conditions of the Ocean are founded on the observations taken on board the Japanese fleet during the years 1946 to 1952. Among many interesting facts found by the Japanese fleet, we may mention these significant points.
1) In the Ocean, the temperature and chlorinity graph of the sea surface increases in the shape of a parabola as the distance from the pack-ice line increase.
2) Ocean currents computed from dynamic calculation near the Scott Island in 1949 show eastward flow to the north of 67° S, and southward flow along the 180° line to the south of 67° S.
3) The insignificancy of the circumpolar water is due to bottom topography and to small clockwise circulations.
4) The boundary of two currents is a good ground, even in the Ocean, and in the homogeneous area good is not expected.

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According to the data in the seasons of 1962/63 to 1965/66 at least, the main sei grounds generally existed in the sea region between the Convergence and the Subtropical Convergence.
It seems that when the Convergence shifted further south than other seasons, the catch per unit effort of sei whale declined, and in the season of inverse phenomena; it increased.
Accordingly, if such a tendency is evident as a rule, the stock assessment based on the catch data must be corrected by the rate of exploitation caused by the latitudinal fluctuation of the Convergence.

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The published works of the late Dr. Seiji Ohsumi (Gunma, 1930–Tokyo 2019) are presented here as a modest contribution to the perpetuation of his memory. This bibliography was compiled so as to include both his scholarly works and other popular publications targeted toward a general audience. It is grouped into the following four categories: 1. Scientific journal papers (including unpublished works presented to the International

Commission Scientific Committee (IWC/SC)); 2. Books and book contributions (authored works, translations and other contributions such as editorial supervision, commentary, editing and editorial advice); 3. Reports and booklets, and 4. Others. The latter group comprises works published in the Geiken Tsuushin Whales Research Institute/Institute of Cetacean Research (WRI/ICR) Quarterly Newsletter, and other miscellaneous writings such as essays and articles that appeared in various magazines, newsletters and other organizations’ periodicals, most of them in Japanese. Some interviews and website articles are also included as he made it a point to record them among his written works. Scientific works are listed by year of publication and, on the same year, alphabetically by author. Other publications are presented chronologically by group.

During a span of 65 years, he authored and coauthored the 741 works listed in this compilation. Their numbers, by category, are: 286 scientific papers, 58 books and book contributions, 40 reports and booklets, and 357 works in other categories (100 in Geiken Tsuushin and 257 miscellaneous).

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南極海鯨類捕獲調査（JARPA）と商業捕鯨の南極海第IV区で採集された 1,654 個体のクロミンククジラのヒゲ板を用い，ヒゲ板の成長と外縁先端部に出現する V 字形の欠刻について検討した。ヒゲ板長は体長の増加に伴い伸長し，雄は体長 8.0 m 以上で 261.8 mm に，雌は体長 8.5 m 以上で 278.3 mm に達した。欠刻は胎児のヒゲ板には認められなかったが，出生後の体長 5.4 m 以下のヒゲ板全てに認められたことから，欠刻は出生時に形成された可能性が高く，摩耗により体長 6.4 m 付近で完全に消失すると考えられた。

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The bacteriological samples of gastrointestinal contents from the whales in the Ocean stored at -5° and -20° respectively were examined. The number of heterotrophic bacteria in the gastrointestinal contents of baleen whales stored for 4 to 5 months at -5° were from 10⁵ to 10⁶ cells per ml of stomach contents, and from 10³ to 10⁶ cells per ml of intestinal contents. In the samples stored at -20° bacteria in the stomach contents were generally more than that in the intestinal contents. On the other hand, no marked difference in the bacterial population between the two samples was seen in samples stored at -5°. As the chitinoclastic bacteria that survive at low freezing temperature can be detected only in the stomach contents, the bacterial flora of stomach and intestines of the same whale in the Ocean may be different.

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2019 年に再開された大型鯨類の商業捕鯨再開により、捕獲されたニタリクジラの皮から搾油、精製して脂肪酸組成の組成を分析し、過去の文献値と比較した。文献値よりも高度不飽和脂肪酸の含有率が高いことが分かった。また、他の鯨類と高度不飽和脂肪酸の含有率を比較したところ、中程度であることが分かった。高度不飽和脂肪酸を活用したサプリメントの開発が期待される。

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In a long-term, large-scale serologic study in the western North Pacific Ocean, anti-Brucella antibodies were detected in common minke whales (Balaenoptera acutorostrata) in the 1994–2010 offshore surveys (21%, 285/1353) and in the 2006–2010 Japanese coastal surveys (20%, 86/436), in Bryde’s whales (B. edeni brydei) in the 2000–2010 offshore surveys (9%, 49/542), in sei whales (B. borealis) in the 2002–2010 offshore surveys (5%, 40/788) and in sperm whales (Physeter macrocephalus) in the 2000–2010 offshore surveys (8%, 4/50). Anti-Brucella antibodies were not detected in 739

minke whales (B. bonaerensis) in the 2000–2010 surveys. This suggests that Brucella was present in the four large whale populations inhabiting the western North Pacific, but not in the minke whale population. By PCR targeting for genes of outer membrane protein 2, the Brucella infection was confirmed in tissue DNA samples from Bryde’s whales (14%, 2/14), sei whales (11%, 1/9) and sperm whales (50%, 2/4). A placental tissue and an apparently healthy fetus from a sperm whale were found to be PCR-positive, indicating that placental transmission might have occurred and the newborn could act as a bacterial reservoir. Marked granulomatous testes were observed only in mature animals of the three species of baleen whales in the western North Pacific offshore surveys, especially in common minke whales, and 29% (307/1064) of total mature males had abnormal testes. This study provides an insight into the status of marine Brucella infection at a global level.

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This study describes the morphological and morphometrical changes associated with prepubertal ovarian development in the minke whale (Balaenoptera bonaerensis). Ovaries were harvested from 94 immature minke whales caught in the Ocean during the summer feeding season (December-March). Notable differences in ovarian size and morphology were found among animals. Up to 10 folds difference in ovarian weight was found among prepubertal whales of similar body size. During the prepubertal period, ovaries grew slowly and approximately doubled their weight. The morphologies of right and left ovaries were almost identical while the growth of the ovary appears to occur preferentially on the right side. The most striking morphological feature was numerous small antral follicles less than 5 mm in diameter found in ovaries of younger immature whales. The occurrence of these ovaries was highest in whales less than 6 m long and gradually decreased as body length increased. In larger whales, the occurrence of ovaries with a smaller number of follicles up to 10 mm and thick tunica albuginea increased. Thus, the ovary of the minke whale experiences bursts of small follicular development during the early prepubertal period before becoming a more developed ovary with fewer but larger follicles, and thick tunica albuginea.

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This study describes a paternity method based on microsatellite DNA genotypes to estimate the abundance of mature male

minke whales (Balaenoptera bonaerensis) in the Indo-Pacific region of the using a maximum likelihood approach. The analyses were based on biological and genetic (microsatellite DNA at 12 loci) data from minke whales collected by surveys of the Japanese Whale Research Program under Special Permit in the -Phase II (JARPAII) in the Indo-Pacific region of the . A total of 2,126 minke whales taken in the austral summer seasons 2006/07, 2008/09, 2009/10, 2010/11 and 2011/12 from locations 35°E to 145°W were used in the analyses. The abundance of mature males estimated by this method was then extrapolated to estimate total abundance for comparison with results for abundance obtained using conventional line transect methods in the research area. The total abundance derived from the paternity method (ca. 210,000–220,000) was generally lower than that obtained by the line-transect method (ca. 260,000–410,000), although the figure from the line-transect method was within the 90% confidence interval of the estimates by the paternity method, and the area covered by both methods was slightly different. Additionally, the geographical locations of mother/fetus–father pairs provided the opportunity to evaluate the current hypothesis on population structure of this species in the Indo-Pacific region. Results for the geographical distribution of mother/fetus–father pairs were generally consistent with the hypothesis of separate Eastern Indian Ocean and Western South Pacific Ocean populations, because 8 of 10 pairs were found in the expected areas of distribution of either populations. However, two pairs were found in distant areas. As a whole, the results from the present study demonstrated the utility of the paternity method for estimating the abundance of minke whales and for assisting the interpretation of population structure hypotheses.

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A total of 21 papers were presented to the Session 34 titled "Current status of cetaceans and other marine mammals in the North Pacific and other accessory seas". A total of 23 cetacean species occurred mainly in the western North Pacific and other accessory seas was assessed their population status. Reliable abundance estimates for some of baleen whales, such as common minke whales (Okhotsk-west Pacific stock) and Bryde's whales (western stock) which are in relatively good population status, are available based line transect methodology endorsed by the Scientific Committee of IWC. On the other hand, it was very concerned that western gray whales are in critically endangered status. It was noted that population of Steller sea lions have been depleted but magnitude of depletion are different by area. Current research activities on cetaceans and other marine mammals in Asian waters were reviewed with inviting reports from China, Korea, Thailand and USA. Topics of cetacean researches in other oceans; North Atlantic and were also comparatively reviewed, it was noted that Norway has incorporated multi specific management system for cetacean harvest and Japanese research take provides long-term monitoring ecosystem. Some of ongoing advanced research projects in Japan were also reviewed.

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The concentrations of various components of follicular fluid were compared among three groups of follicles (small, <5 mm; medium: 5-10 mm; large, >10 mm) with a control that consisted of the components of umbilical serum using seven pregnant minke whales. Follicular oocytes recovered from the follicles were also used for measurement of oocyte diameter after removing the cumulus cells. The mean diameter of the ooplasm in the oocytes from the large follicles (143.2 μm) was significantly greater than those from the small (127.1 μm) and medium (131.7 μm) follicles, although there were no significant differences in diameter of the whole oocyte and thickness of the zona pellucida among the three follicular sizes. The osmolarity of the follicular fluid from the small follicles (363.3 mOsmol) was significantly lower than that of the medium follicles (388.9 mOsmol) and tended to be lower than that of large (381.9 mOsmol) follicles, respectively, both of which were similar to that of the umbilical serum (379.5 mOsmol). There was no significant difference in the concentrations of all components of the follicular fluid between the medium and large follicles. As compared with the values of the umbilical serum, the total-protein, glucose, albumin and chlorine concentrations of the follicular fluid from the medium and large follicles were significantly higher, and the total cholesterol and calcium concentrations were significantly lower. The concentrations of lactic acid (85.3-136.0 mg/dl) of the follicular fluid from the three groups of follicles were significantly lower than that of the umbilical serum (360.0 mg/dl). Among the follicles, the follicular fluid from the small follicles (136.0 mg/dl) contained a significantly higher concentration of lactic acid than that from the large follicles (85.3 mg/dl). The progesterone concentrations were not significantly different among the fluid from the three group of follicles and the umbilical serum: however, the estradiol 17-β concentrations of the follicular fluid increased with the size of the follicle (14.3 and 34.6 ng/ml for small and large follicles, respectively). These results offer new information concerning whale reproductive physiology, especially for improvement of in vitro oocyte maturation and related technologies in whales.

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Genetic analyses were conducted to investigate the individual identification (and matching) of southern right whales (Eubalaena australis) from samples collected in the austral summer in the Indian Ocean sector of the

(between 80°–135°E, south of 60°S). The study was conducted to evaluate the utility of this approach for studies on site fidelity and range. In total, 157 skin biopsy samples were collected from free-ranging whales during fourteen summer surveys. The DNA was extracted from each biopsy sample, genotyped at fourteen microsatellite loci, sequenced for 381 nucleotides of the mtDNA control region, and the sex determined by the presence of a Y-chromosome specific locus. Eight matches were detected (four males and four females) using individual matching by multi-locus genotypes supported by mtDNA haplotype and sex determination. Where photographs were available, two matches were confirmed by photo-identification. These eight re-samples show that at least some males and females returned to the same feeding grounds across years. The average longitudinal dispersal ranges, latitudinal dispersal ranges and average direct distances between marks and recaptures were: 13°06′ and 7°15′; 1°23′ and 0°47′; and 361 n.miles and 199 n.miles for males and females, respectively. The time spans ranged from 3–13 years with an average of 6.7 and 7.8 years for males and females, respectively. Sampling and matching occurred in an area where visual surveys showed aggregations of southern right whales associated with high krill concentration. The study confirms the feasibility of the genetic approach, but more definitive inferences on site fidelity and movement ranges will require a large number of biopsy samples genotyped, from both south and north of 60°S.

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Tail flukes of the

minke whale fetuses were studied to expand the available knowledge on fetal development, which is relatively understudied, as previous studies are qualitative in nature. Seven measurement points on the tail flukes of 122 fetuses (after conception 12.9 to 259.5 days) were recorded. We quantitatively defined the developmental stages based on the measurements. Tail flukes formed after an estimated fetal age of 57.8 days (9.4 cm) and retained almost the same shape as postnatal at 124.6 days (47.3 cm). The results also revealed that the growth rates differed at each measurement point and each developmental stage.

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The present study was conducted to obtain new information on relationships among serum testosterone (T), estradiol-17 β (E₂), follicle-stimulating hormone (FSH), and luteinizing hormone (LH) concentrations and histology of seminiferous tubules in captured common minke and Bryde’s whales during the feeding season. Blood samples and testes were collected from common minke (n=39 for blood samples, n=15 for testes) and Bryde’s (n=14 for blood samples, n=7 for testes) whales captured from May 2001 to August 2001 in the Western North Pacific. Serum T concentrations, in 35.9% of the common minke and 57.1% of Bryde’s whales, were below the detection limit (< 2.5 pg/ml). There were no significant differences in the serum concentrations of E₂, FSH, and LH among immature, mature common minke and Bryde’s whales except that LH levels of immature Bryde’s whales was higher than those of common minke whales. In most seminiferous tubules of mature whales, only a single-layer of spermatogonia was observed. However, spermatozoa were observed in seminiferous tubules in 2/13 of mature common minke and 4/4 of mature Bryde’s whales with the low or undetectable T levels. These results indicate that the low serum T concentrations reflect the inactivity of spermatogenesis in both baleen whales, and that it is not possible to assess gonadal activity in either common minke or Bryde’s whales using serum sex hormone concentrations during the feeding season.

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The reliability of body condition indicators for the minke whale Balaenoptera bonaerensis was examined. Samples were collected from the Ocean south of 60°S and 70°E to 170°W in austral summer by the Japanese Whale Research Program under Special Permit in the (JARPA). As body condition indicators, blubber thicknesses, girths, LMD-indices (√body length / body weight × blubber thickness), d/r-ratios (blubber thickness/surface body radius), BW/BL³ (Body weight/body length³) and G/BL (Girth/Body length) were used. Blubber was thicker in the posterior than in the anterior of the body and thickest in the dorsal and ventral region near the fluke. The blubber in the mid part of the body was similar in thickness through ventral to dorsal region without just ahead of dorsal fin. The results showed that the medial lateral blubber thicknesses and d/r-ratios were highly correlated with total blubber mass (%sculp) and date, showing that these were simple and suitable body condition indicators for the minke whale. In addition, the precise formulae for estimating the weight of the minke whales (r² > 0.85) were derived using body length and a girth.

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Estimates of several life-history parameters of the pelagic subspecies of Bryde’s whale (Balaenoptera edeni brydei) in the western North Pacific were made based on samples collected from the second phase of the Japanese Whale Research Program under Special Permit in the Western North Pacific (JARPNII) from 2000 to 2016. A total of 730 individuals were sampled in the western North Pacific, between the Japanese coast and 170°E and between 35°N and approximately 42°N. Age information was obtained from earplugs of 475 individuals (65.2%). The growth curves were estimated as L_t=12.65 (1−e^{−0.189 (t+5.250)}) and L_t=13.30 (1−e^{−0.170 (t+4.929)}) for males and females, respectively. The mean age at sexual maturity was estimated as 7.72 (SE=0.49) and 8.56 (SE=0.39) years, and the mean body length at sexual maturity was estimated as 11.41 m (SE=0.25) and 11.75 m (SE=0 .23) for males and females, respectively. The annual ovulation rate was estimated as 0.526/year. Increased readability of earplug age in the JARPNII resulted in improved estimates of age-related life-history parameters for the western North Pacific Bryde’s whale compared with those based on samples collected during the past commercial

period.

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