Rookie, when you say the yote's howling is it after you make a call ?
If thats the case they are wise to you, some one has been calling them and missing with their shots, If they start that howling you need to find another place to call, If when you go into a area and find a place that looks good ,, sit down and get your self ready but wait at least five or ten min's before you start calling, Start your call and for about thirty to forty five seconds, then wait for another five min's, and repeat this five or six times, Most people call too often and too long, I know it's hard to sit there and wait but it pays off in the long run. Make sure you are well hidden and be still,, that is the main thing, Hope this helps rookie, Best of luck, it's a great sport, I have enjoyed it for fifty five years, there is nothing like it.
Best Wishe's Joe