THE PEREGRINE falcon's scientific name is Falco Peregrinus, which means Falcon Wanderer. Three subspecies are recognized in North America: F.P. Pealei from the coastal islands off Alaska; F.P. Tundrius, which nests above the tree line in the Arctic; and F.P. Anatum, which once ranged over North America from coast to coast. In the 1960s, scientists discovered that DDT was interfering in the egg shell formation of meat and fish eating birds. Healthy birds were laying eggs so thin they were crushed by the weight of the incubating adult. By 1965, no Peregrine falcons were fledged in the eastern or Central United States. By 1968, the Peregrine population was completely eradicated east of the Mississippi River. In 1972, use of DDT was severely restricted in the United States and worldwide.
