U.S. birders spend as much money for seed as U.S. gov's donation to Africa

According to John Marzluff's book Welcome to Subirdia p. 82-3


"Across U.S, birders, buy one half milllion to nearly one and a quarter million tons of seed.


Roughly same amount as corn, wheat, rice that U.S. gov donates annually to feed people in Africa.


Annual cost of $3.5 billion.  Hence 350 species of birds has been reported eating at feeders in U.S."