Ten Lions Fall Ill as Temperatures Surge
Three lionesses have died from suspected heatstroke at Tama Zoological Park in Hino, western Tokyo.
The deaths occurred as Japan faced prolonged extreme heat and unusually high humidity.
The lionesses died on July 28, July 31 and August 2. They were aged three, 11 and 15.
Veterinary examinations found severe dehydration and multiple organ failure in all three animals. The final causes of death remain under investigation. However, zoo officials believe intense heat was a major factor.
The health crisis began in mid-July. Two lions first showed signs of illness on July 18.
Their symptoms included loss of appetite, weakness and reduced physical activity. Other animals later developed similar problems.
By July 22, 10 of the zoo’s 16 lions required medical treatment. The affected group included two males and eight females.
Zoo management suspended the public lion exhibition and Lion Bus service from July 23. The closure will continue until the animals’ health improves.
Zoo Expands Emergency Cooling Measures
Zoo employees are using water sprays and powerful fans to cool the animals.
Veterinarians are also providing intravenous fluids, vitamins and other medicines. Three lions remain seriously unwell and are receiving continuous treatment.
Four animals have recovered or are showing signs of improvement. Six other lions have not developed health problems.
The zoo has installed additional spot air conditioners and industrial fans inside restricted lion facilities. The animals will remain away from public areas while treatment continues.
Officials said the zoo already provided shade and ventilation during the summer. However, the sudden arrival of extreme heat placed greater pressure on the animals.
Lions are generally considered capable of tolerating high temperatures. However, Japan’s humid conditions are different from the dry heat found in many parts of Africa.
Zoo management said it was strengthening heat protection across the lion enclosure to prevent further deaths.
Japan’s Extreme Heat Raises Wider Alarm
Several Japanese cities recorded temperatures of at least 40 degrees Celsius during July.
Japan also introduced the term “cruelly hot day” for temperatures above 40 degrees Celsius. The designation is intended to highlight the serious dangers of extreme heat.
Nearly 18,600 people were taken to hospital with heat-related illness between July 20 and July 26. Forty-five people were pronounced dead on arrival, according to Japan’s Fire and Disaster Management Agency.
Japan’s highest recorded temperature remains 41.8 degrees Celsius. It was registered in Isesaki, north of Tokyo, on August 5, 2025.
