For centuries, fishermen in Japan have been creating ink prints of fish and sea species in a practice known as Gyotaku (魚拓) or “fish rubbing” in English. Originally used to record catches or brag about them in front of others, Gyotaku later became a recognized art form. Now, a new study led by two Japanese biologists has found a new use for the fish prints as a research tool for examining marine biodiversity and tracking extinct species.
Yusuke Miyazaki and Atsunobu Murase from the University of Miyazaki in southern Japan studied 261 samples of gyotaku collected from bait-and-tackle shops in local areas with threatened fish species.
“Methods for obtaining historical biodiversity information are mostly limited to examining museum specimens or surveying past literature,” the researchers write in their study. “The present study demonstrates the validity of examining ‘gyotaku’ for historical biodiversity information.”
According to the study, the oldest gyotaku prints date back to 1839, towards the end of Japan’s Edo Period. A collection of these prints is currently held at the Tsuruoka City Library. Others made in the 1850s–60s are kept at the Chido Museum in Tsuruoka and the Homma Museum of Art Sakata, Yamagata Prefecture.
Gyotaku is traditionally created by pressing a sheet of thin Japanese Washi paper onto a fish coated in black Sumi ink. The print usually includes additional stamps indicating the date of the catch, the location, the fisher’s name, a witness’s name, the fish species, and the type of fishing tackle used. While traditional gyotaku was printed by using black writing ink, modern color versions are used today for artistic and educational purposes.
According to the researchers, the “distributional information” provided in Gyotaku prints proved to be a credible data source for identifying dwindling fish populations included in the country’s Red List of endangered species. For instance, out of the tens of prints they collected, the biologists found only one depicting the fish species Sillago parvisquamis around Tokyo Bay, where it’s in danger of extinction. Seven prints of Hucho perryi were found in Hokkaido, while just three prints of Latesjaponicus (or Japanese Lates) were recorded in Miyazaki Prefecture.
“Given the rarity of these threatened species in some regions, ‘gyotaku’ are probably important vouchers for estimating historical population status, and factors of decline or extinction,” the scientists concluded.
But now, gyotaku itself is in danger of extinction. “Storage of gyotaku in the public areas of shops and stores is usually less than ideal, with exposure to tobacco smoke, sunlight, and moisture,” the study says. “This is the main reason for deteriorating gyotaku. In fact, some shop owners reported disposing of older damaged materials.”
Furthermore, the researchers concede that an equal threat to gyotaku is modern technology, as fishers today inevitably prefer to boast their catches in the new documentation form known as the selfie.