Theory 67/Field programme/Predator exclusion
Cascades Need Range Overlap
The claim
Trophic cascade strength in exclusion experiments is set by the ratio of predator range to prey range, so wide-ranging predators produce weak cascades.
01Mechanism
Control requires presence where prey is dense; overlap determines exposure.
02Prediction
Cascade strength should track the ratio.
03Refutation
Strength tracking predator biomass would remove overlap.