Why do blue-jays have the greatest need for self expression?

In "Jim Baker's Blue-Jay Yarn," the author describes for the reader a man by the name of Jim Baker. Jim Baker, a "middle-aged, simple-hearted miner," seems to have an unusual talent in that he can understand animals. According to Jim Baker, the vocabulary skills an animal possesses depends on the kind of animal. Some animals are more proficient with language than others. Apparently, blue-jays are "the best talkers he had found among birds and beasts."
Blue-jays seem to have the greatest need for self-expression because "there's more to a blue-jay than any other creature." Jim Baker seems to think that blue-jays have effective use of grammar and are rarely at a loss for words. He compares blue-jays to humans, sharing that "A jay will lie, a jay will steal, a jay will deceive, a jay will betray." Jim Baker believes that blue-jays are better at swearing than cats, and in short, they are "everything that a man is."