High levels of Mecury found in fish in NPs.

Yeesh, did not expect that.

California has a vast legacy of methylmercury in the environment from mercury used during the gold rush, but that wouldn't migrate to high-mountain lakes, at least not the territory we're discussing. But since a significant amount of air pollution from China reaches the west, it's very possibly from their coal burning. Nice.

ETA my fishing luck/skill assures my continued safety WRT excess mercury consumption via high-country trout.

Same here!

I was listening to a program a week or so back on our local radio, they were talking about old mining activities which caused loads of mercury being washed downstream, most is still held in the muck or has settled out where gold would be found still. Held behind dams etc. It may be with us for generations.
Duane

They recommend only eating one fish a month caught from the American River. Mercury is cumulative. We old farts do not have that much longer to live so probably could eat two fish a month. Would not let my grandkids do that. I will continue to eat all the fish I catch in the mountains!

I knew you'd say that W_D.

It'd be nice if they'd let you know where they caught fish with high levels, but I wouldn't let it stop me either. Even if I ate all I caught it wouldn't be too many.

There's a tremendous amount of literature but we're still not well versed on the fate and transport of this nineteenth century legacy. We do know it attaches to sediment and sediment slowly heads to the ocean.

Mercury in sediment fans

The Yuba, Feather and Bear rivers were hit hard by mine waste, and it was the blocking of navigation on the Sacramento River that put a halt to hydraulic mining. I'm picturing fisticuffs between miners and riverboat captains.

Cheers,