Ecology 6th Edition by Charles Krebs

Exercise 1

Figure 16.21 gives data to show that a majority of biological control successes are attributed to a single species even though several agents have been introduced for each program. Stiling and Cornelissen (2005) present an analysis that shows multiple-releases reduced pest abundance by 27% more than single releases. Discuss why these two sets of data appear to contradict one another.
Reference Figure: 16.21