The publication of Rachel Carson’s Silent Spring in 1962 sent shock waves through state agencies. The following year, in 1963, the Arkansas branch of the Bureau of Sport Fisheries and Wildlife (which later became the US Fish and Wildlife Service) imported grass carp as an organic treatment for catfish ponds. Carp, with their voracious appetites for plankton, were a chemical-free filter. When the approach proved successful, additional species — black, silver, and bighead carp — were brought from Vietnam and Malaysia, and later from China and Russia as well. Without differentiating among the species, agencies like the US Department of...