love to see that the recognition of a dog's natural scenting ability is getting recognition and being used to some specific scent.
Air scenting , trailing , dogs have always done it , sometimes being given corrections to get onto the footstep track .
take a female in season for a walk around the block , or just put her in the back yard , see how many hopeful suitors you will have on your doorstep . That is her vapor wake.
Dogs can assess fairly quickly whether there is something present or not.