Ricardo Rivera, 2009

University of Puerto Rico Bayamon

What's eating you? How predators, parasitoids and cannibals combine to suppress populations of the herbivore Lema daturaphila

A two month study on the population dynamics of the three lined potato beetle Lema daturaphila (Coleoptera: Chrysomelidae) was conducted during the summer of 2009 in the ecological field station Blandy Experimental Farm located in Boyce, Virginia. An estimated life table was constructed using proportions of mortality observed in each different life stage of the beetle. The life table was constructed with the number of egg clutches found throughout the summer on Lema daturaphila preferred host Physalis longifolia. The highest proportion of mortality occurred in the transition from eggs to larvae. The highest mortality factor observed in midsummer was predation, with almost no parasitoidism by the tachinid fly Myiopharus infernalis (Diptera: Tachinidae). The study suggests that the influence from the community of predators and parasitoids is controlling the population decline of Lema daturaphila while its food source availability increases. Investigating the community of predators that control the population growth of L. daturaphila will grant us a potential strategy to apply for biological control of pests such as L. daturaphila.

Blandy REU Program Overview