User blog comment:Miskos3/Fairy Tail 511: The Hell of Starvation, Review/@comment-112.203.149.21-20161121091607

Minerva can probably tell their location due to her magic. Territory is practically a magic that helps it's user perceive that space. And if this is not the case, nearby mages can probably detect Sting's magic and the immense magic of Larcade as well.