November 05, 2009

The Ecological Value of Top Predators

More evidence on top predators and overall health of the land, this time from Isle Royal National Park. Research at Yellowstone NP showed similar conclusions.

More broadly, losing top predators means more "meso-predators," which different, more negative effects on the ecosystem.

Some findings:
  • 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.

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