summer yotes can give you fits. they are well fed, its hot, they don't move alot. but the young of the year aren't the brightest at this time either and are not call-shy and if you can get near a den and "loafing" area they can be trapped fairly easy. For me, i prefer to trap than call, but a canine pup distress has worked well for me in spring and summer. You may not fool mom and dad, but the young you should be able to take out. make sure your set-ups are perfect, they are hard enough to call in when they are hungry, so don't blow what could be a one-time deal. play the wind, and good luck.
p.s. don't give up on your trapping...once you get the hang of it you will really catch the fur.

brian