Thousands of Fish Dead Along Chicago Lakefront

Yet another mass animal death: Along the Chicago lakefront, gizzard shad—a type of herring—are dying off in large numbers. Thousands, maybe more, are dead and frozen or floating in Lake Michigan, the Sun-Times reports. Geese and ducks are feeding on the dead and dying fish. Gizzard shad are fairly sensitive, particularly to drops in oxygen levels; the early arrival of ice in the harbors could also be a factor. One biologist says the situation is abnormal, but click for a possible explanation for all the die-offs.
(More mysterious animal deaths stories.)