Meeting the food demand of the world’s rapidly growing population requires an increase in agricultural productivity. Insecticide use is often promoted as a way to increase yield, however it also causes resistant and new pests that have led to an increase in pest damage and decreased yields. Besides the negative effects on profits, insecticides have been linked to poor environmental quality and can have negative human health effects. Harnessing natural pest control mechanisms is an increasingly promoted approach to reduce pesticide use, increase yield, and improve environmental quality and human health. Bats are a critical component of natural pest management and are estimated to provide billions of dollars’ in pest control services. However, understanding of bat diets and role in agricultural pest control in heavily agricultural areas is limited. By understanding the quantity and identity of pests consumed in relation to availability during the growing season, we can estimate the value of bats to agricultural pest control; providing farmers with relatable information about using bats as part of Integrated Pest Management. We will use next generation DNA sequencing to provide a comprehensive understanding of bat diets from June-October. This information will be disseminated to farmers through the Nebraska Extension offices, the Nebraska Bat Working Group, and a webinar for farmers and extension agents. By understanding the role and value of bats in controlling agricultural pests, we hope that farmers integrate bat habitat and management into an IPM strategy to reduce pesticide use, increase yield and profit, improve environmental quality, and raise the quality of life for farmers, communities, and society.
This research will lead to increased knowledge regarding the type, timing, and amounts of agricultural pests found in bat diets. Specifically, those insect species that two generalist bat species consume throughout the growing season will be compared to the availability of those pests. Using this information, we will quantify the value of pest control services provided by bats to the region. A peer-reviewed publication detailing the findings of this research will be produced to inform the scientific community and farmers of the results.
Sharing results with agricultural producers is critical. To reach farmers, we will initiate an outreach program in cooperation with the University of Nebraska Extension office. Outreach will distribute the results of this study, other studies about the benefit of bats to agriculture, and simple ways to support local bat populations (such at bat boxes, hedgerows, and riparian corridors). Information will also be available on the Nebraska Bat Working Group and Nebraska Extension websites. Finally, we will present the information in a webinar for extension agents and farmers.
Although outside the immediate scope of this grant, the ultimate motivation and desired outcome is farmers adopting Integrated Pest Management (e.g. decrease use of pesticides, increasing bat habitat). Bat consumption of insects results in increased yields, lower insecticide application and costs, increased profits, greater environmental quality, and improved health and quality of life. Additionally, the results of this study could guide further research.
In 2016 we conducted mist-netting to capture bats at two sites near Lincoln, Nebraska. We captured 188 bats at collected 113 guano samples from the Eastern red bat and Big Brown Bat. We placed light traps at 2-4 locations on most of the 22 nights of netting between June and October.
Guano samples were sent to the University of Georgia and anaylized for insecta composition.
Light trap samples are currently being sorted.
Our preliminary DNA results indicate that the 88 samples contained over 500 species of Insecta across 10 orders (figure 1).
These results were compared against the list of corn and soybean pests provided by the University of Nebraska-Lincoln extension. A few samples contained European corn borer and Corn rootworm. However 10-15% of samples contained Arymworm, cutworm, and stinkbugs. 20-30% of samples contained green clover worm, wireworm, and seed corn beetle.
We will attempt to describe how bat diet changes over the season and how that might affect agricultural pests. Additionally, we will finish identifying light trap results and compare diet to insect availability.