Thanks for the interesting talk.
If my neighbour complained about crows predation of song birds, I tell them about snakes and squirrels. I was curious as to why cats didn't show up on the chart. I've heard they eat hundreds of millions of song birds a year in Canada.
I live half the year on Vancouver Island and half the year in Algonquin Highlands, Ontario - think lakes, balsam, white pine, silver birch forest. We have both in both places. The big difference I have noticed is that ravens tend to be solitary whereas crows flock. Also, their vocalizations are so different.
In Ontario, we have lots of blue jays which dominate the feeders and intimidate the other birds except the hairy woodpecker.