I'm going out on a limb here...but...
First off, the beaver, probably, got relocated by some "do-gooder" to that area without checking with the local landowners...the beaver just didn't materialize out of thin air, or "morph" into a beaver from a tadpole...someone dropped it off and it made its way to Bot's GPs' farm.
Secondly, calling in the Fish&Game or the DNR will draw attention to the fact that the furry little chair-leg munchers are on the property...now you got tree-huggers singing "KOOM-BYE-YAH" around the pond with little Japanese-Origami-Candle-Holders floating in the pond...
Hey, wait...Bot, that's it...invite the tree-freaks, have 'em light the candles and with a little luck, they'll burn the damn dam down!
Problem solved! And by no less than short-sighted do-gooders!
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