It’s beach season in Qingdao again. And that means the return of the most menacing sun-protection gear on the planet: the “bandit mask.” These masks are something of a local tradition among middle-aged and elderly women aiming to avoid suntans. (In China dark skin implies laboring, while fair skin indicates a life of indoor leisure.) Masks typically go for around $3, though many enterprising “aunties,” as older women in China are known, make their own.

But this year not only are they braving temperatures as high as 37 degrees Celsius, but they’re also swimming in what some are saying is Qingdao’s worst green algae infestation since 2008 (link in Chinese).

Once a sleepy fishing village renowned for its beer—it’s the home of Tsingtao Brewery—Qingdao is now a major port and center of industry. Its rapid development has seen more and more fertilizer and sewage pumped into the Yellow Sea. The combination of rising temperatures and a steady supply of nitrogen-rich effluent creates a hothouse for enteromorpha prolifera, the type of algae that has bloomed over Qingdao’s seas. Though it’s not harmful, it’s also not great for fishing activity—or for Qingdao’s beach resorts.

Luckily, the locals don’t appear to mind. Here’s a look at how some of Qingdao’s resilient beachgoers are dealing with the tide of green:

Imaginechina via AP Images Keeping the rays at bay.

This round up is via Jiangsu News’ Sina Weibo account (link in Chinese, registration required):

Local fishermen have it less easy: