Abstract
Large carrion is inhabited by highly variable and interactive communities of insects.Positive inter-actions in carrion insect communities have been recently the focus in carrion ecology.In contrast,competition between carrion insects is rather undervalued.Here we provide evidence that blow flies(Calliphoridae)and Necrodes beetles(Silphidae),dominant decomposers of large carcasses in terrestrial habitats,compete over carrion.By reanalyzing the results from 90 pig carcasses,we demonstrated that the contribution of the flies and the beetles to the decay was negatively related.The greater part of the large carrion pool was monopolized by blowflies,whereas Necrodes beetles abundantly colonized carcasses,on which blow flies were less effective as decomposers.In behav-ioral assays,we found that adult beetles killed 4 times more frequently feeding than postfeeding third instar larvae of the flies,with the large decrease in the killing frequency after the larvae reached the age of early third instar.Therefore,adult Necrodes beetles preferentially killed the lar-vae that were before or in their peak feeding.The study provides evidence that the interaction be-tween blow flies and Necrodes beetles is a combination of indirect exploitative effects of the flies and direct interference effects of the beetles(the mixed competition).
基金项目
National Science Centre of Poland(2016/21/B/NZ8/00788)