Bird colonies Refer to your graph from Exercise 6.

(a) Describe the relationship between number of new sparrowhawks in a colony and percent of returning adults.

(b) For short-lived birds, the association between these variables is positive: changes in weather and food supply drive the populations of new and returning birds up or down together. For long-lived territorial birds, on the other hand, the association is negative because returning birds claim their territories in the colony and don’t leave room for new recruits. Which type of species is the sparrowhawk? Explain.