Upcoming! Biwako Museum's 30th Anniversary Special Exhibition 'The Museum as a Time Machine: Lake Biwa Through the Eyes of Ichthyologists' Media Preview to Be Held

Overview

・The exhibition will feature approximately 230 specimens, making it the largest freshwater fish exhibition in Japan.

・Rare natural history specimens collected in Japan during the Edo period by German physician and naturalist Philipp Franz von Siebold—including those of the crested ibis, loach, and Gengoroubuna—will come to Japan for the first time from the Netherlands.

・Fish specimens collected in Lake Biwa in 1879 by the Vega expedition team will be loaned from the Swedish Museum of Natural History and displayed in Japan for the first time.

・Fish specimens collected from Lake Biwa and its surroundings by Dr. David Starr Jordan, a world-renowned ichthyologist at the time, will be exhibited for the first time.

・A concurrent aquarium exhibition, 'Siebold's Journey to Edo and Japan's Freshwater Fish,' will feature live displays of fish species that Siebold brought back and were later described as new species.

・A media preview will be held on Friday, July 17.

Event Details

Period: Saturday, July 18, 2026 (Reiwa 8) to Monday, November 23 (National Holiday)

Hours: 9:30–17:00 (Last admission at 16:00)

Location: Special Exhibition Gallery and Aquarium Exhibition Gallery, Biwako Museum, Shiga Prefecture

Admission Fees: (General Exhibition) Adults: ¥840, University Students: ¥470, High School and younger: Free (Special Exhibition) Adults: ¥340, University Students: ¥270, Elementary, Junior High, and High School Students: ¥170

*To view the special exhibition, a combined ticket for both general and special exhibitions is required.

Media Preview and Opening Ceremony

● Media Preview

Date and Time: Friday, July 17, 16:30–17:30

*For inquiries about the media preview, contact the Planning and Public Relations Department at 077-568-4811.

● Opening Ceremony

Date and Time: Saturday, July 18, 9:45–10:00

Location: Biwako Museum Atrium

Attendees: Vice Governor Higashi, Director Kameda, exhibition collaborators

Program: Speeches by officials, ribbon-cutting ceremony

*As it is believed that Siebold purchased a crested ibis specimen in Ōno, Tsuchiyama Town, Kōka City, Shiga Prefecture, students from local Ōno Elementary School will also attend.

Details of the Special Exhibition

Specimens serve as 'time capsules' that convey past nature to the future. Museums that house numerous specimens can thus be seen as 'time machines' that allow us to understand the past. This exhibition explores what kinds of fish lived in Lake Biwa in the past, traces the changes over time, re-examines the current state of the lake, and considers what we can do for its future.

Lake Biwa has fascinated researchers from Japan and abroad since the Edo period, leading to numerous surveys and specimen collections. This exhibition introduces the history of ichthyological research developed through international collaboration with overseas researchers and museums, and highlights the ongoing appeal of global research activities.

<Edo Period>

The exhibition will display Siebold's collection—including specimens of the crested ibis, loach, and Gengoroubuna—for the first time in Japan, offering a rare opportunity to experience Japan's aquatic environment during the Edo period through actual specimens from that era.

<Meiji Period>

Ichthyological taxonomy research on Lake Biwa flourished most during this period. Researchers from around the world visited Lake Biwa, competing in surveys and collections to discover new fish species—a period that could be described as a 'battle for lake fish.' The exhibition will introduce what these researchers saw and how they advanced their studies.

Ayū specimen collected in 1879 (Swedish Museum of Natural History) Wataka specimen collected in 1879 (Swedish Museum of Natural History)

<Taishō and Early Shōwa Period>

This was a period when the overall picture of Lake Biwa's fish fauna became clear and research greatly advanced. Tanaka Shōho was the first to systematically summarize Lake Biwa's fish fauna, and later researchers from the Shiga Prefectural Fisheries Experiment Station, including Kawabata Shūgorō, enriched the content. Additionally, new species such as the Biwako giant catfish and Iwatoconamazu were described.

Type specimen of the Biwako giant catfish, displayed for the first time (held by the National Museum of Nature and Science)

<Late Shōwa and Heisei Period>

This was a period when human activities significantly altered Lake Biwa's environment. Changes in aquatic environments due to comprehensive lake development, river modifications, reduced spring water, and the impact of invasive fish species led to a decline in many native fish. The exhibition will introduce valuable specimens that convey the changes before and after, such as those donated by the Emperor Emeritus to the Netherlands in 1979.

Understanding the changes during this period provides crucial insights into what is needed to protect Lake Biwa in the future.

Tanago fish that drastically declined in the late Shōwa period. Specimen donated by the Emperor Emeritus in 1979 (held by Naturalis Biodiversity Center)

<Present (Reiwa)>

At the end of this journey through Lake Biwa's history, the exhibition turns to the current state of the lake. It introduces the latest research and conservation efforts by ichthyologists and offers insights into what natural elements we should preserve for the future of Lake Biwa. The exhibition aims to inspire each visitor to consider what they can do for Lake Biwa's future and connect that awareness to daily actions.

Details of the Aquarium Exhibition 'Siebold's Journey to Edo and Japan's Freshwater Fish'

A linked aquarium exhibition will be held alongside the special exhibition. It will feature live displays of Japanese freshwater fish species collected by Siebold on his journey from Nagasaki to Edo and later described as new species by Coenraad Jacob Temminck, the first director of the National Museum of Natural History in Leiden, and Hermann Schlegel, its second director. Alongside, sketches by Edo-period artist Kawahara Keiga and photographic materials of type specimens of freshwater fish will be displayed. By combining historical materials with modern live displays, the exhibition will clearly present the appearance and charm of Japan's freshwater fish from around 200 years ago.

*Type specimen: The specimen used in the scientific paper that first described a species as new, serving as a guarantee of its characteristics.

<Main Live Freshwater Fish on Display (subject to change)>:

Oikawa, Kawamutsu, Numamutsu, Nigorobuna, Gengoroubuna, Yaritanago, Aburabote, Kanihira, Itomoroko, Motsugo, Kamatsuka, Dojo, Minamimedaka, Namazu, Ariakegibachi, Goldfish (Ryukin, Ranchu)

Additionally, fish displayed in the permanent aquarium exhibition (Japanese eel, lotus) will also be highlighted with information panels due to their connection with Siebold.