A persistent drought has decreased the water surface area of Sun Moon Lake.

A persistent drought has decreased the water surface area of Sun Moon Lake, the largest in Taiwan, and may bring some boat services to a halt, United Daily News reported on Wednesday.

As the only natural lake in Taiwan, Sun Moon is usually very deep and boasts green clear water; however, conditions have changed dramatically this year with dropping water levels and rare waves.

The worsening drought has reduced part of the lake to a large area of mud, exposing the "Nine Frogs," an indicator of the water level.

There are fears that if the drought continues, Sun Moon Lake would have to close it's wharfs and cease boat tourism services, according to a deputy director of the lake administration.