Luke E. Dodd

RESPONSE OF NORTHERN BATS (MYOTIS SEPTENTRIONALIS) TO PRESCRIBED FIRES IN EASTERN KENTUCKY FORESTS

Abstract Prescribed fire is becoming a common management tool for restoring forests of North America; however, effects of prescribed fire on forest-dwelling bats remain unclear. During 2006 and 2007, we monitored prey availability, diet, foraging behavior, and roost selection of adult female northern bats (Myotis septentrionalis) before and after 2 prescribed fires in dissected terrain of the Red River Gorge on the Daniel Boone National Forest in eastern Kentucky. Size of home ranges and core areas did not vary between bats radiotracked before and after fires. Bats foraged more often in the vicinity of pine stands than hardwood or mixed stands, and along ridges and midslopes than lower slopes, regardless of burn condition. Home ranges were closer to burned habitats following fires than to unburned habitats. Abundance of coleopterans, dipterans, and all insects combined captured in blacklight traps increased following prescribed fires. Fecal samples of bats demonstrated lepidopterans, coleopterans, and dipterans to be the 3 most important groups of insect prey, with consumption of dipterans increasing after burning. Bats chose roosts that were taller in height and in earlier stages of decay than random snags, and after prescribed fires chose roosts in trees with a greater number of cavities and a higher percentage of bark coverage. More roosts were observed in burned habitats (74.3%; n  =  26) after fires than in unburned habitats (25.7%; n  =  9). The results of this work suggest that northern bats are tolerant to prescribed fire on the landscape pattern and scale observed in this study. Northern bats responded to habitat alterations resulting from prescribed fires through shifts in the location of foraging areas as bats tracked changes in insect availability, and through shifts in the selection of roost trees by occupying trees and snags possessing more potential roosting microsites.

Identification of prey of Myotis septentrionalis using DNA-based techniques

Abstract Identifying and characterizing trophic linkages is fundamental to understanding how prey availability affects predator behavior, distribution, and density, and to elucidating the extent to which predators regulate prey populations. Vertebrate insectivores, such as bats, are a pervasive top-down force on insect populations in forest ecosystems. Bats are predators sensitive to habitat perturbations, whose prey selection behavior warrants further study. We identified trophic connections between a forest bat (Myotis septentrionalis) and its prey by isolating and sequencing cytochrome c oxidase subunit I gene (COI) fragments of insect prey obtained from bat fecal samples. Prey identities were inferred using GenBank and the Barcode of Life Data System (BOLD). We also identified prey remains morphologically from the same fecal samples, allowing comparisons across novel (GenBank and BOLD) and traditional (morphological) techniques. Lepidopterans were the most frequently detected prey in all approaches. Detection of common insect orders varied across procedures (P < 0.001), suggesting methodological bias at coarse taxonomic resolutions. Of the DNA-based approaches, GenBank provided the more diverse assessment of prey. We reveal trophic linkages for northern bats by identifying 20 prey genera and species using BOLD, more than one-half of which were smaller lepidopterans. The disproportionate number of smaller lepidopteran prey (mean [±SE] wingspan 24.2 ± 2.05 mm) exceeded expectations based on field-based assessments. M. septentrionalis is known to use both aerial-hawking and gleaning behaviors. Lepidopteran prey consumed by M. septentrionalis were smaller than reported for conspecfic genera, suggesting this species differentiates itself from sympatric insectivorous bats with the prey it selects.

Habitat Associations of Lepidoptera in the Ozark Mountains of Arkansas

Abstract Lepidoptera were surveyed using blacklight traps during the growing seasons of 2004 and 2005 in two counties that differed in land use patterns in the Ozark Mountains, Arkansas. Marion County is a fragmented landscape; habitats surveyed were upland forest, riparian forest, edge, and field. Crawford County lies in the Ozark National Forest; habitats surveyed were saw, pole, and sapling size classes of timber. Moths ≥20 mm in wingspan were identified and enumerated. A total of 8326 moths of ≥324 species and 22 families were identified and tabulated. The total number of species and family-level composition varied little between landscapes, but the relative occurrence of species varied between landscapes and across habitats. Dominance of common species varied between landscapes with fewer species forming the bulk of the assemblage in the fragmented landscape. Endemism of certain moths in riparian forest suggests this habitat supports many species. In contrast, few species were recorded in field habitats. These data demonstrate the importance of forest habitats for many moth species in the Ozark Mountains. Our study forms a foundation for understanding species richness patterns of Lepidoptera in the hardwood forests of central North America.

Food Habits of Myotis leibii along a Forested Ridgetop in West Virginia

Abstract Data on food habits of Myotis leibii (Eastern Small-footed Myotis) are scarce. We dissected 172 fecal samples collected from 75 adult (29 males and 46 females) and 2 juvenile (1 male and 1 female) Eastern Small-footed Myotis, captured in mist nets along a forested ridge in northeastern West Virginia in 2008. Fecal samples were dissected and prey items identified to the level of taxonomic order and, when possible, to family. Eastern Small-footed Myotis consumed eight orders of arthropods from 11 families. Lepidoptera (moths) composed 41.5% (±1.9 SE) of adult fecal volume and were found in samples of all 75 adults. Coleoptera (beetles) contributed 30.6 ±1.7% to adult fecal volume and were detected in samples of 97.3% of adults (n = 73). Diptera (flies) composed 16.9 ±1.9% of adult fecal volume and were found in samples of 82.7% of adults (n = 62). Fecal samples of adult females contained a higher percent volume of Lepidoptera (45.9 ± 2.4%, n = 46) than samples of adult males (34.6 ± 3.2%, n = 29). These data provide evidence of moderate dietary specialization on Lepidoptera and demonstrate dietary variation between sexes. Data also indicate Coleoptera and Diptera as important taxonomic groups in the diet of Eastern Small-footed Myotis.

Prey consumed by Corynorhinus townsendii ingens in the Ozark Mountain region

ABSTRACT Moths are known to be the primary prey of the Ozark big-eared bat (Corynorhinus townsendii ingens); however, data do not exist as to which species, families, and sizes of moths are eaten. We investigated patterns of prey consumption of C. t. ingens from 2003 to 2005 by collecting discarded moth wings and other insect parts beneath roosts in three maternity areas: north-central Arkansas, northwest Arkansas, and northeast Oklahoma. A total of 42 visits to roosts resulted in 579 remnants of insect prey representing eight insect orders. Of the discarded remains, 57.2% (n = 331) were Lepidoptera, with 81.3% (n = 269) of these identified beyond the ordinal level. Moths representing eight families and 49 species were eaten by C. t. ingens. Noctuidae was the most common family occurring in the diet with 25 species represented. Noctuidae and Notodontidae were typical prey of C. t. ingens in all areas, but consumption of other moth families varied. Corynorhinus t. ingens preyed upon a limited size range of moths, consistent with data for Corynorhinus in other locations in eastern North America. Our data increase the number of species (n = 31), genera (n = 27), and families (n = 3) of moths known to be eaten by Corynorhinus. Because two of the new families of moths documented as prey of Corynorhinus were discovered beneath feeding roosts in Oklahoma on the western edge of our study, we suggest additional surveys are needed at feeding roosts of Corynorhinus in western North America to fully understand the diets of Corynorhinus.

Temporal Changes in Body Mass and Body Condition of Cave-Hibernating Bats During Staging and Swarming

Abstract The rapid colonization of the Pseudogymnoascus destructans fungus across cave systems in eastern North America and the associated bat mortalities (white-nose syndrome; WNS), necessitates studies of cave-hibernating bats that remain unaffected by, or in close proximity to, the leading edge of the fungal distribution to provide baseline predisturbance data from which to assess changes due to fungal effects. Studies of the physiological ecology of cave-hibernating bats during the spring staging and autumn swarming seasons are few, and an understanding of patterns in body condition of bats associated with entry into and emergence from hibernation is incomplete. We sampled bats at the entrance to a cave in Mammoth Cave National Park, Kentucky, during swarming and staging, prior to (2011 and 2012), concurrent with (2013), and following (2014) the arrival of the WNS fungus. We evaluated seasonal and annual changes in body mass and body condition of bats entering and leaving the cave. We captured 1,232 b...

Prey Consumed by Bats Across Central Appalachia Prior to Detection of White-nose Syndrome

ABSTRACT An understanding of prey consumption patterns across bat species is lacking in a community context across Appalachia. This region of North America is of immediate importance to conservation efforts given the emergence of White-nose Syndrome (WNS). We report on prey consumed by 187 bats captured in mist nets from 2006 to 2008 in Kentucky, Ohio, Tennessee, and West Virginia. Results indicate that consumption of arthropod groups varies among bat species and geographic location, but Coleoptera and Lepidoptera were important dietary items across this predator assemblage. We attribute the variation observed across bat species to be due to differences in ecomorphology and foraging strategies. This study provides baseline data for investigating feeding patterns following impacts from WNS in the Central Appalachian region.

Temporal Variation of Nocturnal Lepidoptera and Other Insects at Robinson Forest, Kentucky

ABSTRACT Lepidoptera are a conspicuous, diverse group of forest insects that are responsive to land management and perturbation. Nocturnal Lepidoptera and other insects were surveyed using blacklight traps during June and July of 1997 at Robinson Forest, a large experimental forest located in the Appalachians of eastern Kentucky. Though the capture of Lepidoptera and other common insect orders varied little between sampling locations, a seasonal trend was detected; fewer Coleoptera, Lepidoptera, and total insects in general were captured in June versus July. Lepidoptera ≥20 mm in wingspan were further identified and enumerated. A total of 664 Lepidoptera of ≥100 species and 13 families were tabulated. Species turnover, particularly for the most abundant species, was commonplace between June and July. The food habits of abundant species were varied, suggesting the assemblage of Lepidoptera at Robinson Forest is not only taxonomically rich, but is functionally rich as well.