Fish were dying in Mathews County this summer, and Joe and Sabine Baker of Cobbs Creek saw their share of the carnage.

On four days in August—the 10th, 16th, and 28th-29th—juvenile menhaden entered the headwaters of Cobbs Creek behind the Bakers’ house, schooled up, used all the oxygen, and died.

"It looked like you could walk across the water on them," said Joe Baker.

He said that at first the fish kill was a boon for blue herons, seagulls and crows, but after a while "it got so rank, even they didn’t want ’em." Millions of flies congregated to feast, as well, forming a thick mat across the Bakers’ waterfront backyard.

Finally, Sabine Baker decided to take advantage of the smelly bounty that nature had bestowed, and she emulsified the fish to create fertilizer for her plants and vegetables.

"It smells awful, but it really works good," said Joe Baker.

Mark Alling with the Virginia Department of Environm...