For example, avian regulation of spruce budworm populations breaks down after budworm density exceed a critical level.
(avian regulation of spruce budworm populations; breaks down; T:after budworm density exceed a critical level) (budworm density; exceed; a critical level)
avian regulation of spruce budworm populations budworm density
breaks down exceed
T:after budworm density exceed a critical level
a critical level