Busy as a Beaver

Beaver Dam and Pond near Weir 101

Beavers have recently reoccupied a pond at work (known as the "old" beaver pond, as opposed the the "new" beaver pond a half a mile away or so).  They have built an elaborate dam across the exit of the pond and raised the level 6 inches or more, and flooded a large area of grass around the edge.

Some scientists are less than thrilled about this; one is concerned that the beavers will alter her long-term study of the rate of mercury methylation by freshwater ecosystems.  She has a technician trying to discourage the beavers by tearing a hole in the dam and allowing the water to drain.  However, every time he does, the beavers have the dam repaired and maybe even further reinforced by the next morning.  A bit like a cartoon. I think it would be easier to adapt the science to the beavers, but, maybe that's just me.

Beavers were once hunted to near extirpation in the eastern United States, mostly for their fur which was used to make felt for the elegant top hats of old, and the hunt for more beavers led the mountain men into the west, and helped open the west for settlers.  The fur from the beaver pelts was treated with mercury to make better felt, and this was one of the historical sources of mercury pollution. It also led the term "mad as a hatter" as the felt makers fell victim to mercury neurotoxicity from lingering over boiling pots of fur in mercury solution, and ultimately, the Lewis Carol's famous character, the Mad Hatter.