the other night i was watching a program about killer whales and they mentioned that at the top of the food chain, the killer whales were getting high concentrationof pcb's. thats horrible to think we are poisoning such wonderful mammals, it ends up that alot of the killer whales of cananda are moving out and finding other places to be cuz of the pollutants and kill of there natural food..herring, salmon..but on another note, they showed the same killer whales attacking a baby grey whale, they did not manage to kill it with the mother right there protecting it, but they almost suceeded, but they did eventually kill a baby grey whale in the end..very fascinating stuff..