Ransom is finally good for something besides managing projects.
This morning I made him a coffee and then heard the familiar noise. The water heater, no matter what I do, and the fact that it's newish makes noises randomly and you can hear it all over the house. It's a perfect storm of someone showering while someone else is flushing or something but it will start up and sporadically go for a few minutes and running the hot tap in the master bathtub seems to clear it.
I made a comment that I needed to go fix that and he offered to put a decoy owl up on the roof for me.
It is April Fools Day after all. I'm sorry? What will an owl do?
It will make the Flicker think this territory is already occupied so he'll find somewhere else to drum.
And then it dawned on me. The Northern Flicker birds I feed, and watch drum on other people's vent stacks every time we go for a walk or run are doing the same things here and my mysterious water heater issues that ONLY happen in spring and only for a few minutes and half a dozen plumbers have checked the heater and can't find any problems with it are just birds looking for mates.
(And when I filmed the noise aiming the camera directly at the water tank, of course it was loud. That's where the vent stack terminates. Oh my God.)
Huh.
Decade-old mystery solved right there.