Three lionesses at Tama Zoological Park in Tokyo have died from suspected heatstroke, and seven other lions are under treatment, a zoo spokeswoman confirmed Tuesday. Since mid-July, 10 of the zoo's 16 lions have exhibited symptoms such as loss of appetite and decreased activity. The three lionesses died on July 28, July 31, and August 3, respectively. A veterinarian attributed the deaths to heatstroke, citing dehydration and multiple organ failure. The spokeswoman noted that while lions are generally heat-resistant, Japan's high humidity—unlike the dry heat of Africa—poses a unique challenge. The heat arrived suddenly after the rainy season ended in late July, overwhelming the animals. The zoo is strengthening countermeasures by sprinkling water, improving ventilation, and installing spot air conditioners. This incident coincides with a broader heatwave in Japan, where nearly 18,600 people were hospitalized for heatstroke between July 20 and 26, with 45 deaths. Japan records about 1,300 heat-related deaths annually and aims to halve that number by 2030. Scientists link the increasing frequency of extreme heat events to human-induced climate change. Japan's highest recorded temperature, 41.8°C, was registered in Isesaki on August 5, 2025. Authorities have adjusted cultural and sporting events, including the World Cosplay Summit, due to the heat.