I too have problems with people chasing and photographing my chickesn when I'm not outside with them or at home...and I live in a rural area.  When I am home I am not very friendly when I confront them.  I then advise them that they are stressing my chickens and that affects their egg laying.
I disagree with the others who have posted that your chickens are a nusience.  They are on your property and these people are tresspassing.  Your chickens should be allowed to free range as you want them to,. I would put a sign very prominently on my property that says, "yes, I know they are out" and "Please leave the chickens alone".  Thank you.
 
Unfortunately, people think they are entitled to go on other peoples property and do whatever they want.  The only way these people will stay off of your property and leave your chickens alone is to be blunt with them.
 
Good luck.