Yunnan witnesses largest butterfly emergence in a decade

Two women watch the butterflies in the Butterfly Valley in Southwest China's Yunnan province, on May 20, 2021. [Photo/Xinhua]

Monitoring data show that the aggregate number of butterflies in three major cluster areas in the valley is estimated to be more than three times that of the same period in 2020.

The phenomenon only occurs in Mexico and China's Yunnan. "The ecological environment of the valley is ideal for butterfly breeding, and there are abundant bamboo leaves here which butterflies feed on," said Yang.

The butterfly explosion will last for about 20 days and will likely peak between May 25 and 28, he added.