Primary or apex predators can actually benefit prey populations by suppressing smaller predators, and failure to consider this mechanism has triggered collapses of entire ecosystems.
Cascading negative effects of surging mesopredator populations have been documented for birds, sea turtles, lizards, rodents, marsupials, rabbits, fish, scallops, insects and ungulates.
The economic cost of controlling mesopredators may be very high, and sometimes could be accomplished more effectively at less cost by returning apex predators to the ecosystem.
Human intervention cannot easily replace the role of apex predators, in part because the constant fear of predation alters not only populations but behavior of mesopredators.
Large predators are usually carnivores, but mesopredators are often omnivores and can cause significant plant and crop damage.
The effects of exploding mesopredator populations can be found in oceans, rivers, forests and grasslands around the world.
Reversing and preventing mesopredator release is becoming increasingly difficult and expensive as the world's top predators continue to edge toward obliteration.
"These problems resist simple solutions," Ripple said. "I've read that when Gen. George Armstrong Custer came into the Black Hills in 1874, he noticed a scarcity of coyotes and the abundance of wolves. Now the wolves are gone in many places and coyotes are killing thousands of sheep all over the West."
"We are just barely beginning to appreciate the impact of losing our top predators," he said.