duraboat,

These types of killer whales(transients) do a lot less hunting of salmon then they do of sea mammals. They keep their "conversation" (you know, the clicking and sonar stuff) down to almost nothing so as they can sneak up on other sea mammmals without alarming them of their presence. Other sea going mammals can hear this stuff pretty good. It is because of this "silence" that makes them less effective in herding salmon for dinner. Other resident type orcas actually emit frequencies (conversation -remember they are very intelligent) on how best to organize and attack or chase the salmon as a "pack" -or pod. -They often work closely together and coordinate their efforts. Kinda like how the humback whales in Alaska feed on krill/plankton by working together surrounding the krill by air bubbles and tail thrashing and a bunch of them coming up through the center for a massive feast..... Springer was a "resident" whale or fish eater mostly.
Good Fishing, Darin