  Biological pest control is increasingly used in agriculture as a an
alternative to traditional chemical pest control. In many cases, this involves
a one-off or periodic release of naturally occurring and/or genetically
modified enemies such as predators, parasitoids, or pathogens. As the
interaction between these enemies and the pest is complex and the production of
natural enemies potentially expensive, it is not surprising that both the
efficacy and economic viability of biological pest control are debated. Here,
we investigate the performance of very simple control strategies. In
particular, we show how Pareto-efficient one-off or periodic release
strategies, that optimally trade off between efficacy and economic viability,
can be devised and used to enable high efficacy at small economic costs. We
demonstrate our method on a pest-pathogen-crop model with a tunable immigration
rate of pests. By analyzing this model, we demonstrate that simple
Pareto-efficient one-off and periodic release strategies are efficacious and
simultaneously have profits that are close to the theoretical maximum obtained
by strategies optimizing only the profit. When the immigration rate of pests is
low to intermediate, one-off control strategies are sufficient, and when the
immigration of pests is high, periodic release strategies are preferable. The
methods presented here can be extended to more complex scenarios and be used to
identify promising biological pest control strategies in many circumstances.
