South Korea is facing a difficult winter for its honey makers, as climate change takes a toll on the bees.

For almost five decades, Park Gyeong-je has listened to the gentle humming of millions of honeybees, but lately, he's heard that sweet buzz of silence. Now at the age of 65, Park operates a traditional migratory apiary in South Korea's Sancheong County, packing up his hives and heading across the countryside in the spring to move along with nature's flow of seasonal blooms. It's a soothing, fulfilling career, but, as a Reuters in-depth report reports, the climate change reality of increasing uncertainty is making this ancient trade a wager against nature.

Seasons may come and go unnoticed in an urban, temperature-controlled environment, but not for a person who depends solely on the rhythm of the earth for their livelihood. The old, separate seasons of spring and fall are disappearing altogether, writes Park, leaving behind a "harsh terrain of just winter and summer". The erratic weather has disrupted the natural environment, forcing wild trees and flowers to bloom earlier and for a much shorter time than usual, leaving the bees with a very short season to collect nectar.

The unpredictable climate has also created a short-term physical threat for the insects. Now, worker bees are forced to navigate the hillsides with much greater difficulty and unpredictability during their prime foraging time, as the winds are stronger and more erratic. In addition to the physical pressure of the weather, there has been an increase in deadly biological dangers. Aggressive parasitic mites and exotic diseases have spread more rapidly in warmer, more humid seasonal cycles and can weaken and kill entire colonies within weeks.

Park started with eight hives in 1979 and has expanded to approximately 110 hives with approximately 8.8 million bees, but maintaining these numbers has become more difficult than ever.

This is a local problem in the Korean countryside, but it reflects a wider global trend. The steady disappearance of honeybees is not only a problem for honey producers, but also a concern for the world's food supply, say climate scientists and agricultural experts interviewed by Reuters. Bees are essential for the pollination of many crops grown outdoors and in greenhouses, such as apples, strawberries, and tomatoes. Under extreme environmental stress, bee colonies can no longer pollinate these crops effectively, which can affect food production, prices, and biodiversity.

In response to the changing situation, the structure of the beekeeping industry itself is slowly changing. With the reduction of natural food sources such as black locust and chestnut groves, many beekeepers have been pushed towards artificial feeding techniques to prevent their colonies from starving during the winter.

That results in a difficult situation where bees become less able to forage and survive on their own, while farmers are put under pressure to keep producing more bees, only to lose more colonies to environmental stress, according to experts from local agricultural administration agencies.

In the end, Park's day-to-day efforts to save his millions of little workers offer an insight into how ecosystems are affected by environmental change. When managed bee colonies collapse, it can signal wider pressures on the natural world. As research institutes work on new beekeeping technologies and efforts to breed more climate-resilient bees, the challenges facing beekeepers continue to grow.

Park and other lifelong beekeepers hope that these ecological warnings will be taken seriously before the buzz of the hives grows quieter.