Fresh-water fishermen had better be careful how they use DDT. If they wipe out mosquitoes by treating the breeding places, they may starve the neighborhood fish by cutting off their food supply. That's the opinion of Professor Bertil G. Anderson, who teaches at both Ohio State and West Virginia. He has been studying the effects of DDT on living fish food, and he is alarmed.
The game fish are the topmost rung of a long fish-eat-fish biological ladder. At the bottom are one-celled organismsbacteria, algae, protozoawhich form the prey of slightly larger creatures (tiny crustaceans). These get eaten by the next...