Crop pests eaten by bats in organic pecan orchards Veronica A. Brown a, * , Elizabeth Braun de Torrez b , Gary F. McCracken a a Department of Ecology and Evolutionary Biology, The University of Tennessee, 569 Dabney Hall,1416 Circle Dr., Knoxville, TN 37996, USA b Department of Biology, Boston University, 5 Cummington Mall, Boston, MA 02215, USA article info Article history: Received 12 May 2014 Received in revised form 15 September 2014 Accepted 18 September 2014 Available online Keywords: Pecan Bat Pecan nut casebearer Hickory shuckworm Corn earworm Stink bug abstract Bats are generalist predators of night flying insects, including many crop pests. Attracting bats to agri- cultural areas using bat houses may reduce the numbers of these pests and, consequently, their economic impact. We use real time polymerase chain reaction of mitochondrial DNA found in the guano of bats living in bat houses on organic pecan orchards to document the consumption of pest moth species: pecan nut casebearer, Acrobasis nuxvorella Neunzig (Lepidoptera: Pyralidae), hickory shuckworm, Cydia caryana Fitch (Lepidoptera: Torticidae), and corn earworm, Helicoverpa zea Boddie (Lepidoptera: Noc- tuidae). We also use direct sequencing of insect remains in bat fecal pellets to identify stink bugs consumed by bats in bat houses. Evidence that bats prey upon crop pests is the first step in showing that bats are beneficial to pecan farmers and provides incentives for bat conservation. © 2014 Elsevier Ltd. All rights reserved. 1. Introduction Generalist predators can be effective biocontrol agents by reducing pest numbers, thereby reducing or preventing crop damage (Symondson et al., 2002). As native, generalist predators of night-flying insects, bats serve as significant agents for suppression of insect pests in agriculturally intensive areas (McCracken et al., 2012; Kunz et al., 2011). In particular, Brazilian free-tailed bats, Tadarida brasiliensis I. Geoffroy (Chiroptera: Molossidae), have been estimated to provide $741,000 annually in services by suppressing cotton bollworm (also known as corn earworm on corn plants), Helicoverpa zea Boddie (Lepidoptera: Noctuidae), in cotton fields in south-central Texas (Cleveland et al., 2006). Because of their con- sumption of crop pests, Boyles et al. (2011) cite bats as among the most overlooked, yet economically beneficial, non-domesticated animals in North America. However, predatoreprey relationships can be challenging to document in bats, due to the difficulty of directly observing predation in fast-flying, nocturnal animals. Broad-spectrum insecticides are commonly used to control in- sects, but these insecticides often have serious environmental and economic consequences. To encourage pest suppression by bats in lieu of pesticide use, some organic farmers install bat houses to attract bats to their farms and orchards. However, the consumption of crop pests by bats utilizing bat houses on organic farms has not previously been studied. Pecan (Carya illinoinensis, Fagales: Juglandaceae) is a highly nutritious food product that is widely cultivated in the southern United States and is expensive to produce relative to other nut species (Mizell, 2003). The diversity of pests, the variation of insects among orchards, and the masting trait of pecans make it difficult to attribute crop damage and impact on yield to a particular insect pest (Dutcher et al., 2003). However, the most important pests of pecans include two moth species (pecan nut casebearer, Acrobasis nuxvorella Neunzig (Lepidoptera: Pyralidae), and hickory shuck- worm, Cydia caryana Fitch (Lepidoptera: Torticidae)) and several stink bug species (Wood, 2003). In 2006 in Georgia alone, the costs of controlling A. nuxvorella and C. caryana on pecans were esti- mated at $520,000 and $650,000, respectively (Hudson and Dutcher, 2006). Collecting and analyzing feces can provide a noninvasive and inexpensive method for obtaining genetic material for dietary analysis. Molecular analysis of fecal material allows identification of prey species to taxonomic levels that often are not feasible through traditional fecal analysis. Given the difficulty in capturing and monitoring bats in the wild, noninvasive molecular fecal analysis is particularly promising for studying predator-prey interactions in these volant mammals (Boston et al., 2012). Real time polymerase chain reaction (rtPCR; also known as quantitative PCR) is a highly sensitive method of amplifying a specific DNA sequence. When applied to fecal samples, rtPCR allows screening of many samples * Corresponding author. Tel.: þ1 865 974 3699; fax: þ1 865 974 3067. E-mail address: vabrown@utk.edu (V.A. Brown). Contents lists available at ScienceDirect Crop Protection journal homepage: www.elsevier.com/locate/cropro http://dx.doi.org/10.1016/j.cropro.2014.09.011 0261-2194/© 2014 Elsevier Ltd. All rights reserved. Crop Protection 67 (2015) 66e71