I built my nesting boxes 19 in. off the gound. .is this ok? Do they need a pirch or walkway to walk on in front of the boxes, or will they jump/fly up into them?? I think i may build a walkway that goes along the front of the boxes, but it may act as a roost too, so i don't want it directly in front of the boxes, maybe like 6 or 8 inches away, but parallel to the nesting boxes. .is this ok? will they be able to jump the 6 in. gap and safely jump the gap into the boxes? AND will they jump up onto the railway (19 in) ?? or should i build a little ramp? Thanks. .