übertool: web applications for ecological risk assessment (beta version)
Cloud-based environmental models used by the USEPA for evaluating pesticide risks to ecosystems under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) and the Endangered Species Act (ESA).
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Maximum Sustainable Yield Model Overview


The maximum sustainable yield (MSY) model was developed to maintain the population size at the point of maximum growth rate by harvesting the individuals that would normally be added to the population, and allowing the population to continue to be productive indefinitely. It is based on logistic model and adds a term representing the number of individuals being removed from the population (H):



When the population size is small, its growth rate is low because there are few organisms to give birth. When the population size is large, still, its growth rate is low because the high mortality rate from competition. When the population growth rate reaches its maximum value, the number of individuals that can be added to a population by natural processes is maximized, which equals the maximum harvest rate. If more individuals than this are removed from the population, the population is at risk for decline to extinction.