Trained dog.
I trained my Cocker Spaniel to find them. I swear it took only two minutes. I let her sniff at some Morels and told her to go find some more. Find is a command she is already very familiar with. I wasn't expecting her to get the hang of it so quickly, but within a minute she was barking to let me know she had found some. Result!
Cockers have an, even for a canine, amazing sense of smell and are quite an intelligent dog. She enjoys it and to her it's a game, Cockers do love to play! I can get her to find any mushroom that I can find. That's the only problem, I have to have one to show her before she will find more.