One year ago, almost to the day, How the World Works noted a story in the Sacramento Bee warning of the dangers of a virulent West Nile season -- because mosquitoes were flourishing in the abandoned pools of foreclosed homes.

Today, the Wall Street Journal is featuring a terrific Page One story by Michael Corkery (should be accessible to non-subscribers) on how Northern California government agencies are employing mosquito fish as an abatement technique. The fish are dumped in abandoned swimming pools, and then proliferate like crazy as they scoop up larvae.

There is much to enjoy in Corkery's story, but no shortage of pathos, either. Once they've eradicated the local mosquito population, or a home is successfully sold to new ownership, the fish usually die as the pools are drained or made habitable for humans. "They are sacrificial," says Chris Miller, a biologist at the Contra Costa mosquito and vector control district.

But my favorite part was this:

Not everybody likes turning swimming pools into giant aquariums. "First you have fish, then you have birds that eat them" and then bird droppings, says Arnie Shal, a retired accountant, who lives next to several foreclosed houses with pools in Clearwater, Fla. "It's not really a healthy situation."

Ah, the cycle of life. It's just not healthy.