Control of Corn Earworm using Brazilian free-tailed bats

Project Overview

Project Type: Farmer/Rancher
Funds awarded in 2007: $999.00
Projected End Date: 12/31/2008
Region: Southern
State: Georgia
Principal Investigator:


  • Nuts: pecans
  • Vegetables: sweet corn


  • Crop Production: application rate management
  • Education and Training: extension, workshop
  • Pest Management: biological control

    Proposal summary:

    Corn earworm infestation in sweet corn can cause significant damage to corn crop yields in Georgia. To prevent corn earworm damage, multiple insecticidal sprayings are required. Corn earworm is the larva of the corn earworm moth and each female moth can lay a thousand eggs in her lifetime. With the prevalence of these moths and the short duration of these insecticides sweet corn is a difficult crop to grow sustainably. We propose to demonstrate using the Brazilian free-tailed bat (Tadarida brasilienses) for control of the corn earworm moth. Through the development of genetic markers for the corn earworm moth and other members of the Noctuide family of moths by Dr. Gary McCracken from the University of Tennessee, it has been established that these moths make up the preferred prey of the Brazilian free-tailed bat. Studies in Texas revealed that 80-90% of this bats' diet may consist of corn earworm moths during the peak emergence periods. Over the past 10 years, we have established permanent resident colonies of Brazilian free-tailed bats, numbering about 3,500 during the seasonal peak population. These colonies of bats roost in several bat houses spaced throughout our 27 acre, certified organic pecan grove in Brooks County, Georgia. During the growing season of 2006, we participated in a bat study conducted by Dr. Gary McCracken, in conjunction with the Centers for Disease Control (CDC). Dr. McCracken agreed to run DNA tests for corn earworm moth from guano of some of the sampled bats. The guano tested positive for corn earworm moth. We propose to plant a ¼ acre plot of sweet corn at the eastern edge of our pecan grove. This would place the plot within several hundred feet of bat houses. The bats will be the only control for the corn earworm moth. Dr. Jim Dutcher, an entomologist and one of our cooperators, will be assessing the corn plants for any evidence corn earworm damage or infestation. We will share the results of our project by posting the information on our website. Also we will present the information to other local county extension agent, who has agreed to give joint presentations to local farmers. We also plan to present the results at certified and/or sustainable farm workshops. We regularly give presentations about the benefits of bats, particularly in agricultural settings, and we would include the results of this project in our future presentations. Bat Conservation International will publish an article in their BATS magazine on the results of our project.

    Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.