One hundred and eighty-seven voluntter anglers reported 16,609 rod hours of angling effort on 51 Ontario waters in 2009. A total of 964 muskellunge were landed. Based on the reported angling effort, the catch rate expressed in terms of catch-per-unit-of-effort (CUE) was 0.58 fish/rod hour. All but two angled muskellunge were released alive. One muskellunge was harvested and the other died after handling. A total of 44 muskellunge exceeding 50 inches in length were reported. They were angled from Lake St. Clair (16), Ottawa River (13), St, Lawrence River (6), Lake NNipissing (3), French River (2), Rice Lake n(2) and the Thames River (s). The largexst muskellunge reported in 2009 measured 59.3 inches in length. The mean size of muskellunge angled from Ontario waters in2009 was 37.2 inches. Lamprey attacke was evidence in ten muskellunge angled from the Ottawa River. Six of the fish had lamprey attached when they were landed. Red sores, presumed to be lymphosarcoma, were recorded for five rfish (Pickerel, Rideau River, Scugog Lake, St. Lawrence River and Buckhhorn Lake). This represents an observed infection rate of 0.7%.