Where to find live blackworms?

[thedwightguy]

Blackworms (tubifex) grow in duck crap; run a bucket under water and they clean out pretty quick. Used to get them that way at a duck farm......near Disneyland!

They concentrate into a ball as the feces are removed; you could do it right on the farm, I suppose!

I don't know where or how far down into the ground they go once it freezes, though, considering Saskatchewan is NOT Disneyland.