From Friday night fish fries to shrimp cocktails, people sheltering in place have learned how to cook their favorite dishes at home. As a result U.S. seafood sales have doubled during the pandemic. Globally, the United States ranks fifth in seafood consumption and China—where hunger for seafood has skyrocketed with rising incomes—is number one. While wild fisheries are on the decline, aquaculture is expanding to increase the global food supply. 

“Gui Jie” in Beijing, meaning Ghost Street, is dedicated to crayfish and is filled with towering bright red crayfish statues. While it might just seem like a show for tourists, the Chinese are responsible for 90 percent of the world’s crayfish consumption and crayfish is on menus throughout the country. Between 2006 and 2016, crayfish production more than tripled to 850,000 tons. Surprisingly, crayfish is not native to China but the Chinese began raising them when aquaculture began expanding in the 1980s. 

Fish is brain food. This is a lesson we learned from our mothers and grandmothers. They were right—the Omega-3 fatty acids in fish are good for our health. Omega-3 is an essential fat, but our bodies cannot make it, so it must come from the food we eat, and fish is the best source. Fish, like people, cannot make Omega-3, so they too get it from their food.

Spring is the best time to eat snails, when they are their plumpest, sweet and rich in protein. Snails have been slurped in China for centuries and are an inexpensive treat for a holiday celebration. In contrast to French escargot, which is served with butter and garlic, the Chinese eat snails in stir-fry, braised or boiled and eaten right from the shell. Not all snails are a treat, however, and unfortunately some are extremely damaging to crops and natural ecosystems when they are introduced into a non-native environment. 

In May 2009, I was traveling with researchers from the Shandong Academy of Agricultural Sciences to learn about rural water pollution. One of them realized it was Mother’s Day and decided to treat the 3 mothers in the group to a fishing trip. We soon pulled into a farm with rows of large concrete ponds filled with fish. This was my first introduction to the world’s largest aquaculture industry, where fish are farmed in ponds, reservoirs, and even rice paddies. China produces 50 million tons of seafood annually, far eclipsing the 0.5 million tons farmed in the United States.

The Chinese government is fighting a war on pollution on multiple fronts to protect its air, water, and soil. Despite passage of the stringent Water Ten Plan in 2015, water quality still has not met anticipated targets in one-third of the country. But one Chinese pollution control success story was Beijing’s investments in municipal wastewater treatment plants in the run up to the 2008 Olympics. 

Spreading manure on crops recycles the nutrients, but as it decomposes it releases methane. And lots of it. Agriculture is the largest source of methane emissions globally. Each year, methane from livestock manure has the warming equivalent of 240 million tons of carbon dioxide, or the same as the annual emissions from 52 million cars.