Had something similar happen last summer—thought for sure it was critters, but turned out the previous owner had buried wiring without proper conduit. Moisture got in, corroded everything slowly... ended up rewiring completely. Hope yours isn't that serious!
Had a similar backyard mystery myself, but it wasn't wiring at all. I get why you'd suspect buried wiring issues—especially if the previous owner cut corners—but sometimes it's simpler than that. Last spring, I noticed flickering shadows and weird intermittent lighting in my yard. My first thought was exactly like yours: critters chewing through wires or moisture damage underground.
But after digging around (literally), I realized it was actually just a loose connection inside one of my outdoor fixtures. The wind would blow slightly, and the fixture would shift just enough to make the light flicker. Took me forever to figure it out because I was so convinced it had to be something underground or complicated.
Not saying your issue isn't serious, but before you start tearing up your yard or rewiring everything, maybe double-check the simpler stuff first? Loose bulbs, fixtures, or even a faulty switch inside the house can cause some pretty convincing "mysteries." Learned that lesson the hard way after spending a weekend unnecessarily digging trenches in my lawn...
Anyway, hope you get it sorted without too much hassle. Keep us updated—curious to hear what it turns out to be.
