Tough times, overfishing shake Superior's herring fleet

December 2, 2015 - MPR’s Dan Kraker reports on the decline of lake herring, called cisco in Lake Superior. The fish typically aggregate in thick schools in the late fall when they swim to shore to spawn. But overfishing in parts of Superior regulated by Wisconsin, and a decline in fish survival, have caused cisco numbers on the Minnesota side of the lake to plummet, putting the lake's small but iconic commercial fishery in jeopardy.