| Zoo Name: | Otaru Aquarium おたる水族館 |
| Location: | Otaru, Hokkaido, Japan |
| Coordinates: | 36.7985°N 137.3881°W |
| Num Animals: | 5,000 |
| Area: | 107000m2 (Total area including attached amusement park)[1] |
| Num Species: | 260 |
| Total Tank Vol: | 3500000l (except for the seal and fur seal tanks connected to the sea)[2] |
| Annual Visitors: | 350,000(2006) |
| Members: | JAZA[3] |
| Exhibits: | Harbor porpoise etc. |
Otaru Aquarium (おたる水族館, Otaru-suizokukan) is a public aquarium operated by Otaru Public Aquarium Corporation, Third Sector, in Otaru City, Hokkaido, Japan. It is one of the largest aquariums in Hokkaido, and It is a member of the Japanese Association of Zoos and Aquariums (JAZA).[4] The aquarium is accredited as a Museum-equivalent facilities by the Museum Act from Ministry of Education, Culture, Sports, Science and Technology.[5]
Built in July 1958 as a "marine venue" for the Hokkaido Grand Exposition, the aquarium began operations in 1959 as the Otaru Municipal Aquarium, and with the completion of the new building (now the main building) in 1974, it was managed by the Otaru Aquarium Public Corporation, a third-sector corporation.
The aquarium consists of the main building, which exhibits a wide variety of fish and shellfish, the Dolphin Stadium, which features dolphin and sea lion shows, the Marine Park, where seals, walruses, sea lions, penguins, and other animals are kept, and the amusement park, Otaru Shukuzu Marine Land. The marine animal park is located in a natural cove, where seabirds also fly in. Wild sea lions and largha seals sometimes stray into the park from the coast and are kept there.
The aquarium is usually open from spring break in March (previously April) to November, but has been open in winter since 2006 in conjunction with the Otaru Snow Light Path and the Sapporo Snow Festival.
In 2023, Otaru Aquarium was entrusted with the breeding and operation of AOAO SAPPORO, an aquarium that opened on the fourth to sixth floors of the tower building in Chuo-ku, Sapporo.
The Otaru Aquarium has been actively conducting research activities and has produced research results in the cases of Harbour porpoise and Bearded seal births and artificial nursing.[9]
Jirokichi, a male Harbour porpoise that survived until 2008, holds the record for the world's longest breeding record at 24 years. Jirokichi was protected in 1984 when he was caught in a fixed net off the coast of Sutsu Town in the Goshi region. According to Makoto Oda, the director of the aquarium at the time, she was a juvenile dolphin with no teeth at the time of her protection [She lived at the aquarium until March 25, 2008, although she had lost most of her sight due to her advanced age. She was about 165 cm long and estimated to be 24 years old. In 2007, a [[green turtle]] without a right front fin was protected on the beach in Hatsuyamabetsu Village and has been kept in captivity to this day.[10]