On Wednesday (July 30), an 8.8-magnitude earthquake struck the Kamchatka Peninsula in Russia, triggering tsunami warnings along the Pacific coast in several areas and affecting Japan. Simultaneously, in the city of Tateyama in Chiba Prefecture, Japan, four sperm whales were found stranded on the beach, sparking discussions among Japanese netizens on whether this was related to the earthquake or tsunami, with some expressing concerns that it could be a precursor to a major earthquake.
Experts have clarified that the rare occurrence of multiple whales stranding simultaneously does not have direct evidence linking it to earthquakes.
According to Japanese media reports, the initial tsunami following the earthquake reached Japan on Wednesday morning, leading authorities to issue tsunami warnings for various coastal regions and evacuate residents. On the same day, a man captured footage of the four sperm whales stranded near the coast of Tateyama in Chiba Prefecture.
The tsunami warning coverage by Tokyo Broadcasting System (TBS) included this news, sparking widespread speculation among the public about its connection to the earthquake. It is worth noting that the related video was taken around 5 a.m. local time on Wednesday, while the earthquake occurred around 8:25 a.m., indicating that the whale stranding incident happened before the earthquake.
Sperm whales are the largest toothed whales, reaching up to 18 meters in length and weighing over 50 tons. They are known to live in groups, with small numbers of males and large groups of females and calves forming groups of tens to hundreds of individuals. The stranded whales this time were around 7 to 8 meters long, considered sub-adults. While sperm whales are commonly seen in the waters near Tateyama, stranding events have not occurred there before, adding to the anomaly of the situation.
Miganishi Taeko, a researcher specializing in whales at the National Museum of Nature and Science in Japan, mentioned that while sperm whales are common in the waters near Tateyama, the simultaneous stranding of four whales is extremely rare.
Taeko emphasized that even if abnormal underwater noises are heard before an earthquake, it is difficult to determine the impact on whales. Whales, being mammals that require air to breathe, swim between deep and shallow waters. If they suddenly surface rapidly due to unknown reasons, it could put excessive stress on their bodies.
She further stressed that determining the cause of whale strandings is difficult through observation alone and requires investigations like autopsies to ascertain the cause of death, identify gender, conduct DNA analysis for genetic relationships, and estimate age through teeth analysis to uncover the truth.
Regarding the investigation of this case, Hokkaido University assistant professor Mikka Kuroda stated that on average, there is a whale or dolphin stranding incident daily throughout Japan, indicating these occurrences are not uncommon. Hence, there is currently insufficient evidence to directly link whale strandings to earthquakes.