The occurrence of pinnipeds of the families Phocidae and Otariidae have been documented along the coasts of the Sagami and Tokyo Bays, Japan, based on records present in diverse databases, journals, reports, and articles. This review analyzed historical sightings of Pinnipedia in the Sagami and Tokyo Bays from 1879 to 2023. A total of 37 records encompassing five seal species and three sea lion species were validated, with no reports of walruses (Odobenidae) in the region. Noteworthy findings included two old reports of the Japanese sea lion (Zalophus japonicus), designated as extinct by the International Union for Conservation of Nature, one extralimital sighting of the northern elephant seal (Mirounga angustirostris), and a record of ribbon seals (Histriophoca fasciata) at the southernmost region of Japan. Therefore, this comprehensive review provides valuable insights for future investigations on Pinnipedia.

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The distribution and habitat of Oxynotus japonicus (Squaliformes: Oxynotidae) are reviewed based on seven specimens (514.2–628.1 mm TL) from Sagami and Suruga Bays of southern Japan, and literature records. This paper represents the first record of the species from Sagami Bay based on specimens, and includes a detailed description. The high frequency of occurrence in Sagami and Suruga Bays suggests that both bays provide preferred habitat for this species. This species inhabits steep seafloor topography at depths from 150 to 400 meters, and its distributional range extends from Sagami Bay to Taiwan, in the north-western Pacific Ocean.

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One and two specimens of Cirrhitus pinnulatus pinnulatus Forster, 1801 (Cirrhitidae), widely distributed in the Indo-Pacific tropics and temperate waters, were collected from the Cape Manazuru and west coast of Boso peninsula, Sagami Bay, Japan, respectively. In Japanese waters, C. p. pinnulatus has been recorded from the Izu Peninsula (uncertain east or west coast), Kii Peninsula, Kochi Prefecture, Hyuga-Nada Sea, Satsuma Peninsula, the Osumi Islands, the Ryukyu Islands, and the Izu-Ogasawara Islands. Thus, the specimens described here in detail with supplementary materials represent reliable records from Sagami Bay and northernmost records for the species. In addition, the factors responsible for the occurrence of this species in Sagami Bay were discussed.

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Fejervarya kawamurai is naturally distributed in the western part of Honshu, Shikoku, Kyushu, and the Ryukyu islands in Japan. However, in recent years, this species has also been spotted in the Kanto region. The presence of this species has been confirmed in several areas in Kanagawa Prefecture; however, its detailed distribution throughout Kanagawa Prefecture is unknown. In this study, we surveyed the distribution of this species in paddy fields throughout Kanagawa Prefecture. The presence of F. kawamurai was confirmed in Izumi Ward, Totsuka Ward, Sakae Ward, Yokohama city, Fujisawa city, Yamato city, Chigasaki city and Chuo Ward, Sagamihara city. Continuous distribution of this species was confirmed in the paddy fields along the Sakai river and Hikiji-gawa River, which indicates that this species expands its distribution via paddy field areas. However, enclaved introduction sites were identified approximately 16 km away from other introduction sites. This suggests that this species might have invaded each site separately based on anthropogenic factors.

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