Bats I

Contributed Paper
ROOM: HCCC, Room 16

8:10AM Models for Emerging Diseases of Wildlife: White-Nose Syndrome
Robin Russell; Trevor Hefley; Brenna Hyzy; Haoyu Zhang; Anne Ballmann; Jordan Meyer
White-nose syndrome is a devastating disease of bats that has recently emerged in the Midwest. We describe the use of a diffusion model for identifying the location and time of introduction of white-nose syndrome, as well as occupancy models accounting for false-positive detections to estimate the changes in detection and occupancy probability for bats in Wisconsin and Michigan. Both types of models are generally applicable across disease systems. We describe the use of these models as well as results that indicate changes in detection probability for Midwestern bats potentially due to white-nose syndrome, and indicating the estimated location and time of introduction of white-nose syndrome. We discuss future directions and other applications of these models (including modelling the spread of chronic wasting disease in Wisconsin).
8:30AM Estimating Population Sizes of Little Brown Myotis Through Novel Methods and Analyses
Austin Waag; John Treanor; Jess Kropczynski; Joseph Johnson
There is an urgent need to better understand the population ecology of bats throughout North America given the precipitous population decreases that have resulted from white-nose syndrome. To enhance conservation of bat species believed to be at risk of extinction or extirpation, novel and efficient tools are required to assess current population statuses and improve surveillance for potential future population declines. Although numerous field methods and analytical tools are available for gathering and evaluating population-level data, there exists a lack of monitoring tools for biologists in western North America, due to the death of known hibernacula. Here, we present a novel approach by using high-frequency radio-frequency identification (HF-RFID) technology, in combination with an analytical approach unused by wildlife biologists. For use with these techniques, 218 female little brown myotis (Myotis lucifugus) in Yellowstone National Park have been implanted with HF-RFID tags. Three buildings across 39 km of Yellowstone’s northern range, which are used by little brown myotis as seasonal maternity roosts, have been collectively equipped with 6 continually operating HF-RFID readers and 42 antennas. Since 6/19/2017, 1,854,619 detections of tagged bats have been recorded. Using mark-resight models, we estimated pre-partition population sizes at two colonies to be 1012.1 (95% CI = 876.0-1169.2) and 289.7 (95% CI = 254.6-329.7). In addition to population estimates, we will also present data on individual roost fidelity, connectivity between roosts, and seasonal arrivals and departures from summer roosts. Through continuously tracking detections of tagged bats, a dataset has been started that will provide biologists with a tool that can track long-term population trends. These data provided by this monitoring system and mark-resight analyses will allow for estimates of local population sizes to be made and uncover aspects of little brown myotis ecology that will be essential for managing bats populations in Yellowstone.
8:50AM Meta-Analysis of Tree Roosting Bats in Eastern Temperate Forests
Evan Drake; Sarah Gignoux-Wolfsohn; Brooke Maslo
This study aims to group bats into general categories based on roost preferences. This information could streamline conservation efforts. If managers know which bats have similar forest preferences, then they can conduct themselves in a way that will benefit several bat species at once. Previous studies synthesizing bat roost preferences have covered expansive areas with diverse habitats. This diversity may lead to overly general conclusions that do not accurately represent any single region. We conducted a meta-analysis focused on the eastern temperate forests of the United States. From an initial search of 2,564 studies, we compiled 104 datasets representing 13 species of tree-roosting bats and extracted data on roost structure, tree genus, tree health, canopy closure, roost height, diameter, site classification, and season. We used a multivariate analysis of variance to examine differences in roost-site characteristics among species. The most frequently used trees were oaks (Quercus spp.) and pines (Pinus spp.). Bats roosting in foliage favored living trees, while bark roosts tended to be in dead trees. The patterns revealed by the 104 data sets could inform forest management decisions that benefit bats. This information could be shared with local landowners and forests management entities.
9:10AM Predicting Habitat Use By Bats to Protect Bats and Inform Wind Energy Development
Clarissa Starbuck; Carol Chambers
Although wind turbines are a clean source of energy, they incidentally kill many bats and birds. Migratory species have the highest mortality; in 2012, ~600,000 bats died from encounters with turbines in the U.S. alone. Arizona has 28 bat species and a high proportion of migratory species that creates a high risk of mortality from interactions at wind energy facilities. Our objectives are to determine the species composition, bat use, and topographic features that might influence bat movement. Our study area encompassed open grassland and shrubland in northern Arizona that were similar to sites considered for wind energy development. We deployed 34 acoustic detectors (SM3BAT) to sample for bat activity at randomly-selected points that represented a range of measures for each habitat covariate. We surveyed points during spring, summer, and fall of 2016 and 2017 and used SonoBat 3 software to identify bat calls to species or species groups. We used occupancy models to evaluate the effects of landscape covariates on bat activity. The highest bat activity occurred in valleys, lower slopes, and evergreen forests. Since most wind energy development in northern Arizona has occurred on flat slopes, shrubland, and grassland, this indicated that best sites for wind energy might not overlap with best sites for bat use. Our predictive map shows bat use in areas of northern Arizona considered best suitable for wind energy development given acoustic activity.
9:30AM Bat Conservation Outside Conservation Lands: A Case Study From Dry Tropical Monsoon Ecoregion of Sri Lanka
Thilina D. Surasinghe; Gayan Edirisinghe; Dinesh Gabadage; Madhava Boteju; Kalika Perera; Majintha Madawala; Devaka Weerakoon; Suranjan Karunarathna
Mammalian conservation in Sri Lanka has mostly focused in the protected area network which only covers >30% of the nation’s land area. Bats are relatively mobile and their overall fitness depends on landscape-scale features, including habitat suitability both inside and outside protected areas. To study the bat communities outside Sri Lankan conservation lands, we surveyed 58 roosting sites in Maduru-Oya National Park periphery. We recorded 15 bat species occupying 16 roosting sites where Rufous horseshoe bat was the most abundant while the Painted bat was the was the least abundant. Our checklist included six “threatened” and one “near threatened” species. The roadkilled specimen of genus Phoniscus we documented— a genus so far only documented in Australasia— is noteworthy. The roosting sites we surveyed had a substantially lower bat density; each roost mostly had a single species. Since a given species occupied multiple roosts indicating lack of species-specific roost selection. The roosting sites included caves of different sizes, large mature trees, abandoned buildings, and underneath bridges; all roosting sites were located within or in proximity to dense forests. We found no roosting bats in home gardens, agricultural lands, grasslands or scrublands. Although the Park periphery is a part of the buffer zone, many anthropogenic activities are threatening the bat community: felling large trees, slash-and-burn agriculture, agrochemical use, and vengeful killing. We strongly recommend adoption of wildlife-friendly land-use practices in the buffer zone such as forest gardening, agroforestry and integrated farming. Bat conservation in this region should take a landscape-scale conservation approach, which includes Maduru-Oya and other surrounding protected areas into a conservation network. Extents of undisturbed wilderness are dramatically declining in Sri Lanka, thus, conservation efforts must be retrofitted into multiuse landscapes and novel ecosystems like areas surrounding Maduru-Oya Park.


Contributed Paper
Location: Huntington Convention Center of Cleveland Date: October 8, 2018 Time: 8:10 am - 9:50 am