The second, interaction modification, occurs when the donor species alters some other attribute of the transmitter, such as behavior. When predation threatens a prey species, the prey often modify their behavior in order to reduce the chances of coming under the attention of the predator. Dragonfly nymphs are voracious aquatic predators whose prey sometimes include dragonfly nymphs of a different species. When these two predators (one of which will also prey on the other) are given a common prey species, the dragonfly nymph prey often alters its behavior by reducing its activity to avoid predation by the top predator. The combined effects of the dragonfly nymph prey's reduced activity and a shift to some predation of the dragonfly nymph prey by the top predator can reduce the mortality rate of the shared prey item (Wissinger & McGrady 1993; Crumrine & Crowley 2003).