Second, lets note that there are TWO nest boxes.
You might think that is not enough nest boxes, however when they all insist on using the SAME box...
Sometimes there is a back up at the nest box:
|Eureka and Nugget in the box, Myrtle wants in.|
and sometimes those who go broody and therefore hog the best box are forced to share:
|Broody Myrtle forced to share with Eureka|