This morning I checked the bluebird boxes and found this. 
It is just a few blades of dry grass, but it is the beginnings of a bluebird nest. Since I cleaned out all of the boxes last week (see Spring News-April 1), I will now be monitoring the boxes weekly to check for any nesting activity. Regular monitoring is important, for instance, I have learned that Mariton's nest boxes have also been used by black-capped chickadees, tree swallows and house wrens. I also learn how many eggs are laid, how many eggs hatch, and how many hatchlings fledge. Probably most importantly, I know when the fledglings leave the nest. Then I remove the old nest, so the bluebirds can bring in clean material to start a second brood.
My mother (who will be reading this) told me as a child not to play with bird nests, because the mother bird will smell humans and won't come back to the nest. It is still good advice for children, but we now know that most birds can't smell. And two decades of monitoring have taught me that bluebirds will tolerate a fair amount of disturbance. Still, I keep my monitoring to a minimum. I open the box, peek in, count eggs or chicks, then lock it up and continue walking. I probably spend less than 30 seconds at a box. That way I am less likely to attract the attention of predators like raccoons. About 20 yards from the box, I make notes of what I found, which I later enter in a spread sheet at the office.
A few boxes later, I found this completed bluebird nest. This nest was built in less than a week. Truly amazing. If you visit Mariton, I will be glad to tell you which nest boxes are active--so that you can observe from a distance without disturbing the nest.
