In 2017, Lei diversified his inventory by introducing ducks into 6.67 ha of rice fields, and continued his experiment with fish farming in another 3.3 ha of rice fields the following year.

His efforts paid off. In addition to the fish and ducks, he reaped high-quality organic rice as there were no chemical fertilizers or pesticides used, so as not to poison the animals raised in the fields. The organic rice, a much sought-after product among China's high-income earners, can be sold for 10 to 20 yuan per kg.

To kill insects, Lei relies on solar insect killer lamps and has planted vetiver grass as a repellent.

However, the growing number of uninvited guests such as wild boars and monkeys has become a nuisance. "Five mu (3,300 square meters) of rice fields were ravaged by boars, and monkeys stole bamboo shoots grown on 3 mu of my land," the farmer complained.

Lei is one of the many farmers troubled by increasing wildlife numbers in the area. They frequent farmlands and villages as their habitats keep improving.

Xiao Yingzhong, an official with the Jianyang Forestry Bureau, said forest vegetation recovered after years of conservation, which has boosted biodiversity and increased the number of wild animals, as ecological farming lures them further into the fields.

Located at the foot of the Wuyi Mountains, Jianyang boasts abundant forest resources and is an important area for wildlife conservation.

Xiao said 80 percent of wild animals in Jianyang are well protected now, thanks to persistent efforts to improve conservation infrastructure and crackdowns on pollution discharge, poaching and illegal logging.

The egrets will launch their invasion again, and boars and monkeys are coveting the crops too. Lei has a slim chance of winning the war, but he was quick to see the silver lining.

"By selling organic rice, I can earn at least 6,000 yuan per mu (667 sq m), much more than the old days even if the egrets gobble up all the fish," Lei said.

Hu Defu, a professor at Beijing Forestry University, said wildlife habitats have been damaged by human activity for a long time. However, as the environment improves, some wild animals see immediate restoration of their population and it is their turn to invade the working and living spaces of people.

"In some places, the government has been subsidizing farmers for losses caused by wildlife," Hu said. "Local governments should come up with a proper subsidy mechanism for farmers having such problems."