Congress ordered the study after scientists discovered genetic material of Asian carp near Lake Michigan. More carp DNA was discovered last year in Sturgeon Bay in northern Lake Michigan, some 250 miles from stretches of the Illinois River where the fish are known to spawn. It is unclear if the DNA is from actual fish or came from the feces of birds flying from areas where the carp are commonly found, since the genetic material can stay for days in the guts of birds before being expelled.