Kumano-nada is known for its industry in which cetaceans are used as a resource, including whale watching and dolphin fishery. However, information on the cetacean fauna of Kumano-nada remains insufficient. Therefore, in this study, we investigated the cetacean fauna and their occurrence patterns during fall and winter in southern Kumano-nada by analyzing sighting data recorded during dolphin drive fisheries in Taiji, Wakayama, Japan. In total, 22 species (Mysticeti: five species, Odontoceti: 17 species) were identified from 31 fishing season datasets. Thirteen species with relative frequencies of >50% were categorized into four groups: species with a peak occurrence in September–October, species with a peak occurrence in November–December, species with a peak occurrence in January–February, and species without a peak occurrence. Four species for which sighting rates declined owing to the Kuroshio meander were noted, and the distribution of two of these species, short-finned pilot whales and pantropical spotted dolphins, may be strongly affected by the Kuroshio current. In addition, a substantial mixed-species group of melon-headed whales or pygmy killer whales and Fraser's dolphins was confirmed.

　The effect of temperature and irradiance on the photosynthesis of a tropical seagrass, Halodule uninervis, from Amami-Oshima Island, Kagoshima, Japan, close to the northern distributional limit in the western Pacific, was determined using a pulse amplitude modulation (PAM)-chlorophyll fluorometer and dissolved oxygen sensors. The response of oxygenic photosynthesis to irradiance (0–1000 µmol photons m^－2 s^－1) at 15 and 24℃ revealed that the maximum net photosynthesis (NP_max) was 14.7 and 51.9 µg O₂ g_ww^－1 min^－1, respectively. The temperature response of gross photosynthesis (8–40℃) showed that the highest gross photosynthetic rate occurred at 30.5℃ (T_opt^GP). In contrast, the temperature response of the maximum quantum yield (F_v/F_m) of photosystem II after 3 days of cultivation in darkness revealed that F_v/F_m gradually increased to the optimal temperature (T_opt^Fv/Fm) of 23.9℃, then gradually declined at higher temperatures. The combined effects of 12-hour chronic exposure to temperature and irradiance at 15 and 24℃, under 300 and 1000 µmol photons m^－2 s^－1 showed that the depression of F_v/F_m was more pronounced under low temperature with high irradiance, indicating the occurrence of chronic low temperature-light stress.

　In order to achieve a more efficient means of promoting ovarian maturation and spawning of the Pacific white shrimp Litopenaeus vannamei, we evaluated the reproductive performance of female broodstock subjected to unilateral eyestalk ablation compared to that of non-ablated individuals under laboratory conditions. Two consecutive experiments were conducted for a period of eight weeks each, and in both experiments, animals were fed at a rate of 10% of total biomass in each tank. In Experiment I, with the aim of determining an appropriate feeding regimen suitable for re-circulating systems, animals were fed with two dietary regimens: commercial formulated pellets only, and a combination diet of formulated pellets and fresh polychaetes (Nereis sp.). In terms of the incidence of gonadal maturation and number of spawned eggs, unilaterally-ablated shrimp fed the combination diet showed the most satisfactory results. Therefore, in Experiment II, we utilized the same treatments in order to demonstrate the validity of this methodology. The results demonstrated that L. vannamei broodstock can be readily matured and spawned under laboratory conditions, but that it is necessary to include live feeds in the diet in order to achieve a higher rate of maturation and spawning.

　A sampling of whole horse mackerel and sardine was conducted at randomly selected fresh fish retailers in special wards of Tokyo, and quality was investigated using Fish Analyzer^TM Pro. We then used principal component analysis and cluster analysis in an attempt to develop a typology of retailers' sales strategies. The quality survey revealed that most of the sampled fish were not suitable for raw consumption and that the range of fat content was particularly large for sardines. Statistical analysis suggested that the strategies of fresh fish retailers could be classified into four categories, indicating the usefulness of using datasets that include quality information to classify retailers' sales strategies.