Optimising control of invasive crayfish using life‐history information

Abstract

Summary Optimisation of control methods of invasive species using life‐history information may increase probability that techniques will be effective at reducing impacts of nuisance species. The northern crayfish, Orconectes virilis , has negatively affected native flora and fauna throughout the world in areas where it is non‐native. Yet, life history of invasive populations has rarely been studied. We investigated the life history of three introduced populations of O . virilis within Arizona streams using mark–recapture methods and a laboratory investigation of reproduction to identify times and techniques to maximise effects of mechanical control. We show the most effective time to implement crayfish control efforts is in autumn during their mating season, prior to onset of colder temperatures, at which time the majority of O. virilis become inactive. To improve crayfish survival, recapture and population density estimates, we suggest a mark–recapture programme using a robust sampling approach concentrated during spring and autumn. Identification of vulnerable points in the life history of nuisance species may aid in control efforts.