Workers in hazmat suits used a fish-killing chemical to rid a San Francisco lake of invasive species – a major step toward turning the area into a nature preserve.
The San Francisco Chronicle says the carcasses of carp, goldfish, sturgeon and other species floated to the surface Wednesday, several hours after nearly 50 gallons of rotenone was dumped into Mountain Lake.
The goal is to make room for the introduction of native species like three-spined sticklebacks, Western pond turtles and chorus frogs at the lake in the Presidio.
Rotenone is a plant-based chemical that is widely used to rid lakes of alien fish. Officials say it is not harmful to birds or humans, and all traces of the chemical disappear from water in several days.