Three lions at Tokyo's Tama Zoological Park have died due to suspected heatstroke, as the country endures one of its hottest summers on record, a zoo spokeswoman confirmed.
Since mid-July, 10 of the 16 lions at the zoo have shown symptoms such as loss of appetite and lethargy. Three lionesses died over the past week, with the latest death reported on Tuesday.
The zoo's veterinarian suspects heatstroke as the cause, citing signs of dehydration and multiple organ failure. Despite lions’ natural heat tolerance, the combination of Japan’s intense heat and high humidity poses a unique challenge compared to the dry heat of Africa.
"Heat arrived suddenly after the rainy season ended in late July," the spokeswoman said. The zoo has intensified its heat mitigation efforts by sprinkling water, enhancing ventilation, and installing spot air conditioners to protect the remaining lions, some of which are still receiving treatment.
Japan’s Record Heat and Its Impact
Japan recorded its highest temperature of 41.8°C in August 2025, and this summer has seen multiple days classified as "cruelly hot" due to extreme heat and humidity. Between July 20 and 26 alone, nearly 18,600 people were hospitalized for heatstroke, with 45 fatalities reported upon arrival at medical facilities.
The government aims to halve heat-related deaths, which currently average around 1,300 annually, by 2030. Scientists link the increasing frequency and severity of heatwaves in Japan to human-induced climate change.
Adjustments and Precautions
- Event schedules, including cultural and sporting activities, have been shifted to cooler times to reduce heat exposure.
- Public awareness campaigns have been intensified to prevent heat-related illnesses.
- Zoological parks and animal care facilities are adapting protocols to safeguard animals vulnerable to heat stress.
