Study: Bats help protect tropical plants

PANAMA CITY, Panama, April 9 (UPI) -- U.S.-led scientists say they've discovered bats play a major role in protecting tropical plants from damage by insects such as beetles and caterpillars.

Researchers at the U.S. Smithsonian Tropical Research Institute in Panama City, Panama, have determined bats in a Panamanian lowland tropical rainforest can consume approximately twice as many plant-eating insects as do birds.

The scientists said their study is the first to compare the ability of bats and birds to protect plants via insect predation in a natural forest ecosystem.

The researchers separated the insect-control effects of bats and birds by placing netting over five common tropical plant species only at night or only by day. Uncovered control plants accessed by both bats and birds lost 4.3 percent of their leaf area to insect herbivores. When only birds were excluded, plants lost 7.2 percent of their leaf area. When only bats were excluded, plants lost 13.3 percent of their leaf area, demonstrating that in a tropical forest bats can be more effective pest control agents than birds, the researchers said.

Smithsonian short-term fellow Margareta Kalka, Professor Elisabeth Kalko of the University of Ulm and Smithsonian postdoctoral fellow Adam Smith report their findings in the journal Science.