2006 Northeast Bat Working Group
East Stroudsburg, PA
Northeast Bat Working Group 2006 Presentations
(*) denotes designated presenter. For information only- not necessarily in order of appearance. An agenda is available for download here.
Individial state reports from ME, NH, CT, VT, MA, MD, NY, PA, NJ, VA, RI, DE, OH, WV, KY and others
Presented by an attendee representing their home state
Jacques P. Veilleux - New Hampshire; Melissa Craddock - New Jersey; Al Hicks - New York; Cal Butchkoski - Pennsylvania; Scott Darling - Vermont; James Kiser - Kentucky; Dana Limpert - Maryland; Karen Morris - Maine
Hibernacula Identification and Study Technique
John Chenger*, Melissa Craddock, & others
The PA Game Commission and the NJ Division of Wildlife will present a program on what constitutes a good hiber site and some procedures on sampling methods and safety considerations. Immediately following this there will be a field trip available to up to one or more of three gated hiber sites nearby in the Delaware Water Gap National Recreation Area. Program: Tuesday, January 10, 6:00 PM at JR Grill/Budget Inn meeting room, more info near the top of this page.
Application of Night Vision Imagers for Bat Studies
Bruce Sabol* and Chester Martin*
Studies of nocturnal animals require special imaging equipment to see and record their activities. Three fundamentally different types of night vision imaging equipment have been employed in the study of bat activity. The basics of these different imagers are reviewed and examples of their use in bat studies are presented. Considerations involved in capturing and interpreting imagery of bat emergences are discussed. Further, we present procedures and reliability estimates for an automated emergence counter, using digital image processing technology. Other potential uses, including population estimates during torpor and hibernation, are discussed.
Wind Turbines and Bat Research: Purpose, Standardization and New Technology
A simple method of quantifying transmitter signal strength
Radio transmitters have the potential for varying considerably in signal strength, especially among the small 0.3-0.5 gram models used in bat research. It is in the researcher's best interest to make sure that units are functioning within acceptable limits before incurring the expense of capturing and tracking the animals. This mini-workshop will demonstrate an inexpensive, uncomplicated means of quantifying transmitter strength in your own back yard. This workshop has been successfully tested on a sample of universally challenged biologists from NY, VT and the FWS. It can certainly work for you.
Comparative Ecophysiology in Bats: Seasonal and Stress-responsive Changes in Glucocorticoid
My current research aims to understand reproductive behavior and physiology in bats within the context of their natural environment. My research has been particularly concerned with how animals adapt to both environmental and social stressors and how variations in this adaptability are related to changes in life history stage, reproductive state, and behavior. I will describe some of my previous research in little brown myotis (Myotis lucifugus) as well as my plans for comparative studies between little brown myotis and big brown bats (Eptesicus fuscus) in Pennsylvania. Due to their exceptionally high energetic intake and output and their need to tightly balance energy resources over variable seasonal conditions, small temperate bats in their natural environment provide an excellent system in which to examine seasonal fluctuations in metabolic hormones, such as glucocorticoids (GC). Of particular interest are the physiological signals that drive the fattening and the increased locomotor behavior that occurs prior to migration and hibernation.
Spring emergence tracking of Indiana bats in NY State during 2005
Alan Hicks*, Mike Clark, Mike Cooper, Robyn Niver, Carl Herzog
Spring emergence tracking of Indiana bats was conducted at the Glen Park Caves, Jefferson County NY and the Walter Williams Complex, Ulster County NY during April of 2005. Animals were released at night and a circling aircraft determined their initial direction of travel. Subsequent day searches with aircraft located animals on their day roosts by searching in the direction indicated during the release night. We were able to locate 26 of 32 animals released at the Glen Park caves and 16 of 18 released from the Williams Complex. Glen Park animals stayed within 15 miles (24 km) of the release site, Williams within 40 miles (64 km). Most roost was located under 540 ft (180 meters) elevation. All but one of the 16 from the Williams roost was located in the same two areas as the sample of 11 animals we tracked during 2004. This is despite substantially different methods used to select animals for marking in each of the two years. Five were in very close proximity to roosts used by animals the previous year. One was found in the same tree and another in the same woodlot as animals tracked last year. Results to date suggest that the potential range of M. sodalis within NY appears to be limited, and the animals are not randomly distributed within that range.
Understanding the effects of wind turbine mortalities on bat populations using stable Isotope and genetic variability analysis.
Agencies responsible for addressing the effects of wind turbine mortalities on bat populations are faced with a nearly impossible task. Given the rapid pace of construction, the large number of turbines expected, and mortality rates observed thus far, it seems likely that population level effects on red (Lasiurus borealis), hoary (Lasiurus cinereus)and silver-haired bats (Lasionycteris noctivagans) may occur before we have the resources, methodologies, or time, to determine base line population levels for these species. Stable isotope analysis of hair has the potential for determining the summer origin of animals killed by wind turbines. An analysis of the genetic variability of turbine killed bats at the DNA level may hold the promise of providing baseline estimates of the effective population size and population trends existing at the onset of the wind turbine event. Analysis of kills occurring several years later may indicate changes in population size or trends that could be directly linked to this new source of mortality. I am suggesting that regulatory agencies across the country require that developers pay for initial post construction monitoring, and allow the free access to sites by researchers. Collected specimens will be archived at a central location with samples available for this and other studies. Developers will pay for the storage and required analysis of recovered specimens on the project sites. In this manner, we may be able to establish the population level effects of wind turbines on bats, with the costs being incurred by those that are specifically causing the problem.
Developing an Automated Bat Counter for use at cave or mine entrances
In nearly every state in the Northeast, if not the country we suspect there are large numbers of bats wintering in caves or mines that cannot be entered, or are too dangerous to enter. Others are interested in verifying the results of winter surveys or determining the dates of spring emergence or fall arrival. The solution to all is an automated counter that could be installed and left unmanned through the spring or fall season , except perhaps to change batteries or download data. It seems reasonable that an automated counter comprise of two banks of light beam switches using inexpensive and existing technology, could tell us when, and in which direction, a bat passes, and keep track of the total number of animals entering or leaving a site. I suggest that we jointly fund, through a multi-state, and multi- regional SWG grant (or other sources) a contract with an engineering school (or perhaps a competition within or between schools) to design and build the hardware and software associated with the device to our specifications. The resulting design should make is relatively inexpensive and easy for any state to build as many systems as they would like.
Predictive modeling efforts in NY for small-footed and Indiana bat summer habitat
Jesse W. Jaycox, New York Natural Heritage Program
NY DEC A mark retention-survivorship study update
Alan Hicks, Nancy Heaslip, Calvin Butchkoski, Mike Clark*, Mike Cooper, and Carl Herzog
Although PIT tag marking holds great promise for use on a wide variety of bat species, we do not yet know the mark retention or survival rates associated with this technique. This is especially true for animals marked during the spring emergence or fall swarm, the only two periods when most cave bat species, including the Indiana bat (Myotis sodalis) are available to researchers in large numbers. This study is intended to determine the retention and survivorship rates of banded and Pit tagged animals marked during these periods. Animals were captured at the entrance of the Canoe Creek mine, Altoona PA and randomly selected to be marked in roughly equal numbers. They were marked with either a singly alloy wing band, two alloy wing bands, an alloy band and a PIT tag, or an alloy and plastic wing band. Animals were marked during August 16-18, 2004 (N=981) April 20-22, 2005 (N=715) and August 29, 2005 (N=225). Preliminary tabulation suggests that roughly 15 marked animals were recaptured at the mine entrance during April and August of 2005 among the roughly 6,000 to 8,000 bats that were handled. This might suggest a recapture bias; however, winter surveyors saw only about 30 banded animals among the 25,000 counted during the 2005 winter survey of the mine. It is clear that our recapture rates are too low at Canoe Creek to provide meaningful results, at least for animals marked during the fall. It is also clear that we either killed nearly every bat we handled, or there are a great many bats that visit the Canoe Creek Mine each fall that do not winter there. We have test banded several hundred animals at the Main Graphite Mine in the Adirondacks of NY in hopes of finding a friendlier place for recaptures.
The use of passive acoustic monitoring as a biological assessment tool for surveying migratory patterns of bats in relation to wind power development
Scott D. Reynolds, North East Ecological Services
Wind resource development has been growing more rapidly than any other energy sector, and the impact of this growth has finally reached the northeast. Concern over the potential impact of wind farms on bats, and in particular the potential risk of mortality for the endangered Indiana bat (Myotis sodalis), has resulted in pre-construction surveys at several proposed wind farms in Vermont, New York, and Massachusetts. In 2004, we used passive acoustic monitoring at multiple high elevation ridge top sites during both the spring and fall migratory season. Data collected at these sites suggest that most of activity during the migratory period occurs at low heights (less than 5m above ground), although some bat activity was heard at turbine height (50m). The data suggest that hibernating migratory bats (Myotis spp.) and non-hibernating migratory tree bats (Lasiurus spp) differ in both the temporal and vertical spatial patterns. The ridge top sites surveyed in 2004 appear to have low levels of migratory activity at turbine height.
Predicting minimum habitat requirements of the Indiana bat in the Champlain Valley
Kristen Watrous, University of Vermont
Predicting potential habitat across a landscape is extremely challenging for rare species. Analyzing habitat requirements using partitioned Mahalanobis D2 methods avoid pitfalls commonly encountered when surveying elusive species that typically have small sample sizes and low detection probabilities because it is based solely on data collected at known species locations. Minimum habitat requirements are determined by examining a principal components analysis to determine habitat characteristics that are consistent across known locations. The goals of this study were to (1) document and compare the minimum habitat requirements of Indiana bats (Myotis sodalis) in the Champlain Valley across 7 spatial scales and (2) map potential habitat for the species throughout the same area. We radio-tracked 24 female Indiana bats to their roost trees and across their nighttime foraging areas, and collected habitat characteristics at 7 spatial scales: 1) roost trees, 2) 0.1 ha circular plots surrounding the roost trees, 3) home ranges, and 4-7) 0.5 km, 1 km, 2 km, and 3km buffers surrounding the roost tree. Fifty roost trees were identified and found to be tall, large diameter trees with exfoliating bark, located typically at low elevations and close to water. Trees in the plots surrounding roost trees were typically smaller in dbh, shorter in height, and healthier than the central roost trees. Fourteen home ranges were found to be in areas of diverse, patchy land cover types that were close to water, with an east-facing aspect. Across all landscape extents, the total area of forest within roost tree buffers and the aspect across those buffers were the two most consistent features. Predictive maps indicated that suitable habitat ranged from 4.7% to 8.1% of the total area examined depending upon the number of components used, and was distributed throughout the Champlain Valley. However, information is needed on birth and survival rates to assess habitat quality in the region.
Daily and Seasonal Patterns of Bat Activity along Central Appalachian Ridges
Keith Lott, University of Maryland Center of Environmental Science, Appalachian Laboratory
For this study I attempted to identify the climatic variables that may influence bat activity along ridges in the central Appalachian Mountains. In 2004 and 2005 Anabat units were attached to fire/observational towers along forested ridges in the central Appalachians. The number of calls per night was compared to regional weather data collected at Department of Transportation sites located throughout the state. As of 17 November 2005 I have had 1128 survey nights across 6 locations. Over 51,300 calls have been identified as closely to species as possible. Though my study locations range over 2,277 km2, activity levels between sites seem to fluctuate simultaneously. This would indicate that some landscape scale variables are influencing the activity levels of bats along these ridges in this region.
Roosting Habits of Myotis leibii at the Surry Mountain Lake Dam in Southwestern New Hampshire
Jacques Veilleux, Franklin Pierce College
Indiana Bat Spring Migration Telemetry from Blair Conty, PA to Carroll County, MD
Cal Butchkoski*, John Chenger, Greg Turner, Chris Sanders, and Stacy Wolbert
In April 2005, a total of 6 Indiana bats were radio-tagged and released as they exited the Hartman Mine in an attempt to find additional local maternity roosts and/or follow them to more distant summer roosts. The initial plan was to release the radio-tagged bats around midnight with the plane in the air and ground vehicle strategically stationed on high points. The ground crew would track 1 to 2 bats and collect as much behavior information as possible. The aircraft would keep track of as many bats as possible. The project was successful in following migrating Indiana bats for a record 135 km (84 mi) and 148 km (92 mi) from a hibernaculum.
Summary of Bat Conservation and Management 2005 Survey Projects
Dana Borgstrom, John Chenger*, Matt Clement, Kaitlin Frantz, Kevin Rhome, Todd Sinander
In 2005 BCM participated in several winter surveys, one spring telemetry project, 5 acoustic surveys, 6 mist net surveys, 3 BCI workshops, two abandoned mine assessment projects, one mine mapping survey, and one unusual bat exclusion. Project locations were in PA, NY, WV, IA, NM, and AZ. This work will be briefly summarized.
State Wind Farm Bat Protocols & Monitoring Discussion
Scott Darling*, Greg Turner*, and an ensuing free-for-all