STOW CREEK TOWNSHIP — What killed 200 red-winged blackbirds in South Jersey?

The Department of Environmental Protection is stumped, after an investigation into the death of the birds in Stow Creek Township in Cumberland County in late November was "inconclusive" as to a cause of death.

In a statement, the DEP said it conducted tests for necropsy, toxicology and histopathology, and it does not appear that pesticides were the cause. Wheat seed from a nearby field tested negative for anything unusual.

"Information provided by the farmer to DEP’s Bureau of Pesticides indicated that the seed was treated with the fungicides difenoconazole, Mefenoxam and Sedaxane and the insecticide Imidacloprid. These compounds are not considered to be very toxic to birds and likely did not cause the deaths," the DEP said in a statement.

The DEP said the birds suffered internal bleeding and trauma because when they hit the ground.

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