Same. According to the article, ours is the largest of the sub-species, but I can't see them grabbing a chick or duckling, much less a kitten.Are we talking about the same birds?
https://en.wikipedia.org/wiki/Blue_jay#
Here they are much smaller than the crows. - Or we have larger crows?
Maybe our (very large crows and ravens) have been colouring their feathers? Or they turned blue from the cold?