The annual production (P) of Orconectes virilis between the summers of 1976 and 1977 in Dock Lake was 52.5 kg/hectare. The annual P/ ratio was 1.8, while the mean biomass () was 28.7 kg/hectare. On nearby Shallow Lake during the same time period the annual production was 43.8 kg/hectare. The annual P/ ratio was 1.5 and the mean biomass was 29.6 kg/hectare. Compared to several similar Michigan lakes (surface area 1.4-1.9 hectare) annual production and mean biomass values are lower in the Ontario lakes (surface area 1.2-1.6 hectare). The crayfish in the Ontario lakes have a faster growth rate, earlier age at maturity, and higher mortality rates. The P/ ratio compares to those recorded for other species and regions of the world. Thus far annual P/ ratios reported in the literature vary from 0.5 to 2.0.
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Walter T. Momot (1978) studied this question.