WildBryanWood - Since the pictures I have acquired two more of the gourd style set-ups.
LBD - I have been known ( Pellets ), to rehome a Sparrow or two that try to bully the Martins. My wife's cats welcome them with open paws.
987Ron - They do seem to like them.
oldrivers - We had , I think, 14 nesting females last spring.
Ganchik - Thanks
JimJakosh - I think I'll make some plugs shaped like the gourd style to put in the holes. Seems to keep out unwanted birds more.
LesB - We have a lot of the Swallows flying around all the time but have no idea where they are nesting.