Yeah. It literally only tells you when it's within vision. It kinda seems only really useful if you're traveling around anyway and happen to get the message. If you're already actively hunting spawn locations for it, doesn't really do a lot of good. And that's with me personally disagreeing that they're hard to see. Only time I really have difficulty with anything blending in is if it happens to be spawned around a group of the same mob type. And even then, they still tend to stand out a little bit.