In this map, the distribution of AFOs and fishkills is shown on the largest map with a 3.5 mile radius around human-caused fishkills. The percentage of the total number of fish killed between January 1981 and November 2001 attributed to certain causes is broken out in an inset. According to records kept by the DNR, the number of fish killed for the stated period as a result of manure spills is far higher than any other category (61%). See larger map (2,596kb pdf file) /  See DNR source page.