Harvesting of Benthic Algae by Territorial Grazers: The Potential for Prudent Predation

manipulate and quantify the relationship between chlorophyll a biomass and `4C productivity for various algal assemblages. We observed an asymptotic relationship between algal productivity and biomass over a sixteen-fold range of algal standing crops, which differs from the hump-shaped relationship expected for populations following logistic growth. Our results demonstrate that primary productivity would increase significantly if Leucotrichia maintained a higher algal biomass within its territory (e.g. by reducing its short-term harvesting rate), which implies that it is not a prudent predator. Because some of this production is consumed by territorial intruders, however, the yield to Leucotrichia may be maximized at a lower algal biomass than that which maximizes total productivity.