A report by three federal agencies shows live Asian carp do not have to be present for their DNA to turn up in the environment.
The report identifies six other ways genetic material from bighead and silver carp may have reached waterways in the Chicago area and western Lake Erie. It says the DNA may have come from storm sewers, fisheries sampling gear, fish-eating birds, dead fish carcasses, barges and sediments. The report says carp DNA from those sources could remain in place for several days. Asian carp DNA has been found in dozens of water samples beyond an electronic barrier meant to prevent the fish from reaching the Great Lakes. Scientists are concerned the carp could destroy the lakes multi-billion dollar fishing industry.