Survey of Bats on the Mid-Columbia National Wildlife Refuge 

Complex and Little Pend Oreille National Wildlife Refuge, 

Washington, October 2011–May 2012 

U.S. Department of the Interior

U.S. Geological Survey

Open-File Report 2013-1120

Survey of Bats on the Mid-Columbia River National 

Wildlife Refuge Complex and Little Pend Oreille 

National Wildlife Refuge, Washington, October 2011–

May 2012 

By Joan C. Hagar, U.S. Geological Survey; Tom Manning, Oregon State University; and Jenny Barnett, 

U.S. Fish and Wildlife Service

Open-File Report 2013–1120

U.S. Department of the Interior

U.S. Geological Survey
U.S. Department of the Interior

SALLY JEWELL, Secretary

U.S. Geological Survey

Suzette M. Kimball, Acting Director

U.S. Geological Survey, Reston, Virginia: 2013 

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Suggested citation:

Hagar, J.C., Manning, Tom, and Barnett, Jenny, 2013, Survey of bats on the Mid-Columbia River 

National Wildlife Refuge Complex and Little Pend Oreille National Wildlife Refuge, Washington, October 

2011–May 2012: U.S. Geological Survey Open-File Report 2013-1120, 30 p. 

Any use of trade, product, or firm names is for descriptive purposes only and does not imply 

endorsement by the U.S. Government.

Although this report is in the public domain, permission must be secured from the individual 

copyright owners to reproduce any copyrighted material contained within this report.
iii

Contents

Introduction.................................................................................................................................................... 1

Study Area..................................................................................................................................................... 2

Methods......................................................................................................................................................... 3

Mine Shaft and Adit—Little Pend Oreille National Wildlife Refuge............................................................. 3

Winter Surveys—Columbia National Wildlife Refuge and Hanford National Monument/Saddle 

Mountain National Wildlife Refuge ............................................................................................................. 3

Spring Surveys—Columbia National Wildlife Refuge................................................................................. 4

Processing Acoustic Data .......................................................................................................................... 5

Results........................................................................................................................................................... 5

Winter Surveys—Columbia National Wildlife Refuge and Hanford National Monument/Saddle 

Mountain National Wildlife Refuge ............................................................................................................. 5

Discussion ..................................................................................................................................................... 7

References Cited........................................................................................................................................... 8

Appendix 1. Dates and Locations of Deployments of Acoustic Bat Detectors at Columbia, Hanford 

NM/Saddle Mountain, and Little Pend Oreille National Wildlife Refuges, Winter 2011–2012 ...................... 23

Appendix 2. Recording and Displaying Bat Acoustic Transects................................................................... 25

Appendix 3. Bat Survey Transect Routes and Bats Detected, Columbia National Wildlife Refuge, 

Washington, April 2012................................................................................................................................ 28

Figures

Figure 1. Wetlands and rimrock habitat on Columbia National Wildlife Refuge, Washington...................... 10

Figure 2. Location of Little Pend Oreille Refuge and Bear Mountain Mine Adit and Shaft, Washington. .... 11

Figure 3. Bat detector deployment at study sites. ....................................................................................... 12

Figure 4. Bear Mountain mine at Little Pend Oreille National Wildlife Refuge, May 2012........................... 13

Figure 5. Acoustic bat detector deployment locations and number of bat detections (n) at Columbia 

National Wildlife Refuge, Washington, December 2011–January 2012....................................................... 14

Figure 6. Location of stationary bat detectors deployed in April 2012, Columbia National 

Wildlife Refuge, Washington........................................................................................................................ 15

Figure 7. Species composition of bats detected at Columbia National Wildlife Refuge, Washington, 

April 17 – 27, 2012 ...................................................................................................................................... 16

Figure 8. Index of bat activity (number of bats calls per hour) by date at Columbia National 

Wildlife Refuge, Washington, April 2012...................................................................................................... 17

Figure 9. Average, minimum, and maximum nighttime temperatures (°F) on dates of bat detector 

deployments, Columbia National Wildlife Refuge, Washington, April 2012 ................................................. 17

Figure 10. Total number of bat calls detected as a function of time of night, Columbia National 

Wildlife Refuge, Washington, April 17–27, 2012.......................................................................................... 18

Figure 11. Bat guano found under bridge where McManamon Road crosses Lower Crab Creek, 

Columbia National Wildlife Refuge, Washington.......................................................................................... 19
iv

Tables

Table 1. Names, call frequency groupings, and conservation status of bat species that potentially 

occur on refuges of the Mid-Columbia National Wildlife Refuge Complex, Washington .............................. 20

Table 2. Dates, times, coordinates, and results of winter driving transects to detect bats at Columbia 

National Wildlife Refuge, Washington.......................................................................................................... 20

Table 3. Total number of bats by species or call frequency group and detection rates (average

calls/hour; based on 5 s recording length) at the Bear Mountain Shaft, May 9–15, 2012 ............................ 21

Table 4. Bat species, and weather conditions at times of bat detections, December 2011–January 

2012, Columbia National Wildlife Refuge .................................................................................................... 21

Table 5. Total detection and detection rates (average calls/hour; based on 5 s recording length) of 

bats by species at seven sites on Columbia National Wildlife Refuge, Washington, April 17–27, 201222

Table 6. Locations, dates, times, and results of acoustic transect surveys for bats in Columbia National 

Wildlife Refuge, Washington, April 2012...................................................................................................... 22

Conversion Factors

Inch/Pound to SI

inch (in.) 2.54 centimeter (cm)

inch (in.) 25.4 millimeter (mm)

foot (ft) 0.3048 meter (m)

mile (mi) 1.609 kilometer (km)

SI to Inch/Pound

centimeter (cm) 0.3937 inch (in.)

meter (m) 3.281 foot (ft) 

kilometer (km) 0.6214 mile (mi)

kilometer (km) 0.5400 mile, nautical (nmi) 

meter (m) 1.094 yard (yd) 

Temperature in degrees Fahrenheit (°F) may be converted to degrees Celsius (°C) as follows:

°C=(°F-32)/1.8. 

Temperature in degrees Celsius (°C) may be converted to degrees Fahrenheit (°F) as follows:

°F=(1.8×°C)+32. 
1 

Survey of Bats on the Mid-Columbia River National 

Wildlife Refuge Complex and Little Pend Oreille National 

Wildlife Refuge, Washington, October 2011–May 2012 

By Joan C. Hagar, U.S. Geological Survey; Tom Manning, Oregon State University; and Jenny Barnett, U.S. Fish 

and Wildlife Service

Introduction

Bats are diverse and abundant in many ecosystems worldwide. They perform important 

ecosystem functions, particularly by consuming large quantities of insects (Cleveland and others, 2006; 

Jones and others, 2009; Kunz and others, 2011). The importance of bats to biodiversity and to 

ecosystem integrity has been overlooked in many regions, largely because the challenges of detecting 

and studying these small, nocturnal mammals have rendered a paucity of information on matters as

basic as species distribution and natural history attributes. Recently, concern for bats has arisen in 

response to recognition of large-scale threats, such as white-nosed syndrome (WNS; Turner and others, 

2009; Frick and others, 2010) and mortality at wind energy facilities (Arnett and others, 2008), factors 

that are causing unprecedented population declines of bats (Boyles and others, 2011). WNS is a fungal 

disease that has killed more than 1 million cave-hibernating bats in eastern North America since being 

discovered in New York State in 2006 (U.S. Fish and Wildlife Service, 2012). WNS has spread rapidly 

from northeastern U.S., and as of August 2012 has been confirmed as far west as eastern Missouri(U.S. 

Fish and Wildlife Service, 2013). Given the rapid spread of WNS, there is concern that the disease may 

soon affect western bat populations. 

Hibernating bats are particularly vulnerable to the effects of WNS (Blehert and others, 2009). 

Refuges in eastern Washington, including the Mid-Columbia River National Wildlife Refuge Complex 

(MCRNWRC) and Little Pend Oreille National Wildlife Refuge, support many potential hibernacula. 

Sixteen species of bats potentially occur on these refuges, including one federally listed species of 

concern (Townsend’s big-eared bat [Corynorhinus townsendii]; see table 1 for scientific names of bats), 

and 12 species that are of conservation concern in Washington and Oregon (table 1). However, little is 

known about bats on these refuges because few surveys have been done, and none have been done 

during winter. Refuge biologists are lacking even the most basic information, such as species presence, 

and location and status of hibernacula. In order to assess vulnerability and develop a strategy for 

management of WNS, refuge managers need to know where bats are hibernating, and which species are 

using each hibernaculum. The goal of this project was to provide information on the status of wintering 

bats to refuge biologists and managers in order to support decision-making that might minimize the 

threat of WNS in western bat populations. We conducted surveys of bat activity in winter and early 

spring as an initial step toward identifying bat species that may be over-wintering and locating potential 

hibernacula on these refuges. Our specific objectives were to identify bat species using the refuges, to 

identify areas of resident bat activity in autumn, winter, and early spring using acoustic bat detectors, 

and to try new methods for quick surveys of bat activity. 
2 

Study Area

The MCNWRC is comprised of seven refuges and one National Monument (NM) in eastern 

Washington and Oregon. At least four of these (Hanford Reach NM/Saddle Mountain National Wildlife 

Refuge (NWR), McNary, Umatilla, and Columbia) have potential hibernation habitat for bats, based on 

the availability of extensive cliff and rocky outcrop habitat. Sixteen species of bats potentially occur on 

the refuges (table 1). Nine species have been confirmed on Hanford Reach NM, where limited summer 

surveys have been conducted (Soll and others, 1999). Other refuges in the complex have never been 

surveyed. 

Hanford Reach NM/Saddle Mountain NWR, McNary, Umatilla, and Columbia Refuges are 

located in the semi-arid shrub-steppe of the Columbia Basin Plateau and host shrub-steppe, riparian, 

wetland, and cliff, rimrock, and outcropping habitat. All but Columbia are adjacent to the Columbia 

River. Refuge riparian and wetland habitats provide potential foraging areas for bats, while cliffs and 

cliff crevices potentially support roost sites and hibernacula for some species (fig. 1). We conducted 

winter bat surveys in Columbia and Hanford/Saddle Mountain Refuges in December 2011 and January 

2012. As a follow-up to winter surveys, we re-surveyed Columbia Refuge in April 2012. 

Little Pend Oreille National Wildlife Refuge (LPO) is located in Stevens County, Washington, 

approximately 10 mi southeast of Colville (fig. 2). Located on the western slope of the Selkirk 

Mountain Range, it is dominated by mixed-conifer habitat types. As with MCNWRC, LPO lacked 

information about bats on the refuge, including a basic species list. The presence of abandoned mines on 

the refuge suggests the potential to support hibernating bats, as abandoned mines are often used as 

hibernacula by bats (Sherwin and others, 2009). A survey of abandoned mines conducted on LPO in 

1996 (Block, 1996) to assess safety hazards and potential impacts to aquatic biota revealed a total of 11 

mines on and adjacent to the refuge. During subsequent field work in 1995 and 1996, evidence of 

underground workings were found only at Bear Mountain Shaft (vertical passage) and Bear Mountain 

Adit (horizontal passage). The location of Bear Mountain Shaft (shaft) and Bear Mountain Adit (adit) 

was poorly documented, and had never been visited by current refuge staff. Although Block (1996) 

found no evidence of bat use during their brief survey of the Bear Mountain Adit, refuge staff wanted to 

locate the mine, precisely record the location with Global Positioning System (GPS) coordinates, and 

assess the shaft and adit for bat use and public safety issues. Both the shaft and adit are in remote, high 

elevation locations, accessed by jeep trails and walking. Access during winter would be made even 

more difficult by deep snow. The shaft is located on a ridge top and is approximately 4 m deep. 

Although the ridge is dominated by grass and shrub communities, the shaft itself is located in a small 

grove of conifer trees. In spring 2012, about 3 m of water was standing in the shaft, suggesting limited 

access to the mine (fig. 4). The adit is located on a steep, densely vegetated slope, approximately 190 m 

north of the shaft. The adit goes straight into the mountain side (fig. 4), beyond the 150 m surveyed by 

Block in 1996. Vegetation surrounding the adit is very dense, consisting of alder and coniferous forest.
3 

Methods

We used Pettersson D500X detectors (Pettersson Elektronik, Uppsala, Sweden) for acoustic 

surveys. Each detector was powered by a 6-V gel-cell battery. Because we had only four detectors with 

which to sample a large area of potential habitat, we subjectively selected locations for detectors where 

we thought bat activity was most likely to occur. These locations included areas between rimrock cliffs 

(potential roosting habitat) and open water (potential foraging habitat) at Columbia Refuge, and near 

areas of open water, springs, or tree cover at Hanford. Detectors were deployed in waterproof housing, 

with microphone cables running through 2.4-m sections of 5.1-cm polyvinyl chloride (PVC) pipe, 

which were erected and stabilized with three guy lines attached to tent stakes (fig. 3). Microphones were 

oriented approximately 90 degrees from adjacent cliff faces to avoid echoes and capture calls of bats 

moving between cliff and water. The PVC poles were painted to blend in with the surroundings, to help 

minimize human interference. 

We obtained raw weather data for a weather station near Columbia NWR (Warden Golf Weather 

Station) from the AgWeatherNet network (www.weather.wsu.edu). We determined air temperature (°F), 

relative humidity (percent), and wind speed (mph) for the closest 15-min interval on the range of dates 

during which acoustic detectors were deployed in winter, and used hourly records for the April survey at 

Columbia NWR. 

Mine Shaft and Adit—Little Pend Oreille National Wildlife Refuge 

On October 4, 2011, Inventory and Monitoring Biologist Jenny Barnett, Refuge Biologist Mike 

Munts, and former refuge manager, Steve Fowler, located the Bear Mountain mine shaft and deployed a 

bat detector. On October 17, 2011, the bat detector was moved from the shaft to the adit. Locations of 

both mine shaft and adit were documented with a GPS. Stationary detectors were again deployed at the 

same locations at Bear Mountain Shaft and Adit from May 9 to 15, 2012. 

Winter Surveys—Columbia National Wildlife Refuge and Hanford National Monument/Saddle 

Mountain National Wildlife Refuge

Winter surveys were conducted at Columbia NWR and Hanford NM/Saddle Mountain NWR 

from December 5, 2011, to January 17, 2012. Originally, we intended to conduct preliminary surveys 

during the autumn, when pre-hibernation swarming can indicate the composition and numbers of 

species that use a site, particularly those species that may easily be missed during winter hibernation 

counts (Bat Conservation Trust, 2007). However, due to delays in funding, we were unable to begin 

field research until December 2011. 

Stationary detectors were deployed at 16 sites at Columbia NWR (fig. 5) and 12 sites at Hanford 

NM/Saddle Mountain NWR (appendix 1). Detector settings were: 

• Frequency: 500 

• Pre-trigger: OFF

• Length: 1–3 s 

• Input level: 80 

• Trigger level: 80 

• Interval: 0

Data from each detector were recorded on two compact flash (CF) cards. After 6 to 8 nights of data 

collection, data cards were downloaded and bat detectors were moved to a new location. 
4 

Driving transect surveys were conducted on 9 dates between December 13, 2011, and January, 

12, 2012, beginning with 30 min of sunset (table 2). The observer drove an approximately 3-km-long 

route that passed within 0.4 km of deployed stationary detectors to allow for a comparison of detection 

rates between the two methods. At the beginning, end, and every 0.4 km along each transect, the 

observer stopped to deploy a hand-held acoustic detector for 10 min. 

Spring Surveys—Columbia National Wildlife Refuge

We focused spring survey efforts on Columbia NWR to supplement the winter bat detections 

with more information about the species that were present and their activity locations. We conducted 

both stationary acoustic detection and driving-transect surveys at Columbia NWR in April 2012. In 

addition, several locations under bridges and in rimrock cliffs were visually inspected for signs of bat 

roosting. We operated acoustic bat detectors at seven sites (fig. 6) from April 17 to 27, 2012. The 

southern end of the refuge was not well sampled because there was very little rimrock in that area. We 

sampled for 1 to 5 nights at each site, for a total of 27 detector-nights across all sites. As in the winter, 

we placed detectors at subjectively selected locations where bat activity was most likely to be recorded, 

primarily between rimrock cliffs (roosting habitat) and water (foraging habitat). A further consideration 

for placement of detectors was to minimize disturbance by humans by selecting locations behind locked 

gates whenever possible. 

Detectors were set to activate at 15 min before local sunset, and deactivate 30 min after local 

sunrise. Other detector settings were: 

• Frequency: 500 

• Pre-trigger: OFF 

• Length: 5 s 

• Input level: 80 

• Trigger level: 80 

• Interval: 0 

Data from each detector were recorded on two CF cards of varying capacity (2–16 GB), and the CF 

cards were downloaded to a new folder each day. At each deployment, the detector was set to read all 

sectors on the fresh CF cards to ensure that the fresh cards had been re-formatted. 

We modified the protocol for driving transects from that used in winter. We used Myotisoft 

Transect© and TransectPro© with GarminTM and DeLorme GPS instruments, and SonoBatTM 3.05 to 

record and map acoustic transects from a moving vehicle. (See appendix 2, Recording and Displaying 

Bat Acoustic Transects, for protocol and detailed notes on using Myotisoft Transect© software in 

conjunction with GPS instruments). 

Acoustic data were collected on 5 nights from three transects established along pre-determined 

routes. Transect surveys began 30 min after sunset (range of actual start times: 20:17 to 20:25), and 

ended 20–50 min later (range of actual end times: 20:45 to 21:02). We extended the detector’s external 

microphone pointed toward the sky out the passenger window of the vehicle and drove at approximately

20 mi per hour. We recorded any time taken out of the survey for stops made along the way to open 

gates, etc. The longest transect was about 19 km, and the shortest transect was about 9 km. 
5 

Before starting each transect survey, the detector and GPS were synchronized as closely as 

possible (generally within 2 s error). Detector settings were the same as for stationary surveys (see 

above), and the external microphone, attached to the detector by a long cable extending from the same 

PVC pipe used in stationary surveys, was held in place by closing the passenger window of the vehicle 

on the pipe. The microphone was oriented vertically upwards and approximately 30 cm from the roof of 

the vehicle. Two GPS instruments were used for redundancy (a GarminTM GPSmap 60, and a DeLorme 

Earthmate PN-40). Except for stopping to open and close gates, the observer drove at approximately 20 

mph. 

Processing Acoustic Data

All files from stationary detectors were processed with SonoBatTM Batch Scrubber 3 default 

settings (acceptable call quality=0.80, discriminant probability threshold=0.90) to remove files lacking 

signatures of bat calls. Files collected from transects were “scrubbed” of obvious noise files using the 

SonoBatTM D500X Attributer v. 2.2. We used SonoBatTM 3.02 Washington East to assign species 

identifications from call files. We manually examined every single call file and generally accepted the 

classification automatically assigned by SonoBatTM. However, we overrode calls identified as Spotted 

Bat because they were obviously noise. Some files contained calls from two individual bats. In those 

cases, each bat was considered a separate call file. In cases where SonoBatTM did not classify obvious 

bat calls to species, we could often assign them to a call frequency group (table 1) based on visual 

inspection of the sonogram. Because the default criteria we used are fairly rigorous, our results may 

underestimate the number of bat calls actually recorded for both stationary detectors and transects. 

To derive an index of bat activity, we summed the number of files recorded for each detector 

night, for each species and for all calls combined, and divided by the number of hours of detector 

operation. 

Results 

Mine Shaft and Adit—Little Pend Oreille National Wildlife Refuge LPO.— One bat call 

was recorded in October 2011 at Bear Mountain Shaft. It was not identifiable to species, but was 

classified in the 50 kHz group. A total of 216 call files were recorded at Bear Mountain Shaft in May 

2012 (table 3). No bats were detected at the Bear Mountain Adit in either October 2011 or May 2012. 

The standing water in the mine shaft observed in the spring indicates that bats cannot access the mine 

through the shaft during the winter (fig. 4). Therefore, the shaft is unlikely to provide hibernating habitat 

for bats.

Winter Surveys—Columbia National Wildlife Refuge and Hanford National Monument/Saddle 

Mountain National Wildlife Refuge

We recorded nine bats on 6 nights out of 109 detector-nights at Columbia NWR (table 4). Bats 

were detected at four sites (fig. 5). No bats were recorded during 78 detector-nights at Hanford 

NM/Saddle Mountain NWR. We identified canyon bats and a myotis species from the acoustic data. All 

bats recorded were detected early in the night, between 17:28 and 19:56 hours. The average temperature 

(29.6°F) and wind speed (5.1 mph) for all dates from December 1, 2011 to January 21, 2012 for the 

hours between 17:00 and 20:00 were within two units of the averages recorded during times of bat 

detections (table 4). Average relative humidity (RH) for the entire period (77.6 percent) was 8.3 percent

greater than the average RH recorded at times of bat detections. Seven of the nine bat detections were 

recorded before moon rise. 
6 

Stationary Detectors.—We identified 11 species out of a total of 2,846 bat calls recorded at 

Columbia NWR (table 5). Silver-haired bats were the most frequently detected species, comprising 44

percent of the recorded calls (fig. 7). The canyon bat, western small-footed myotis, and hoary bat each 

represented greater than 1 percent of the recorded calls. We recorded no more than 30 identifiable calls 

for the remaining 7 species (table 5). Two species that were infrequently detected, California myotis 

(four detections) and Townsend’s big-eared bat (one detection), represented new species records for the 

MCNWRC. 

We recorded bats on 25 of the 27 detector nights. One detector was set up differently and 

occasionally slipped down the pipe during the night; on one of those occasions (April 24–25 at Crescent 

Lake), no files were recorded. On April 26–27 at Goldeneye Lake, only a few noise files were recorded, 

likely due to equipment malfunction. 

An index of bat calls per hour generally increased over the first 9 days of the 10-day sampling 

period (fig. 8). Nighttime temperatures were mild to warm, peaking near the middle of the sampling 

period on the night of April 22–23 (fig. 9). Bat activity did not clearly correspond with nighttime 

temperatures for the sampling period. However, it is possible that warm weather may have initiated a 

flush of emergence of aquatic insects, resulting in a subsequent period of heightened bat activity in 

response to increased prey abundance. 

More than 80 percent of bat calls were recorded between 20:00 and 01:00 hours; detection rates 

decreased steadily between midnight and dawn (fig. 10). This activity pattern also was evident for 

individual species. In particular, 87 percent of canyon bat calls were recorded between 20:00 and 21:00 

hours. All detectors were deployed by 19:40 hours, but the earliest recording was at 20:10 hours. 

Similarly, detectors were operated until after 06:20 hours, but no bats were recorded after 05:18 hours. 

Transect Surveys.—We verified a total of six bats (four silver-haired bats, one canyon bat, and 

one unknown species from the 40 kHz Group) during five transect surveys (table 6). Bat calls from 

Transect 1 of a quality high enough to be classified by SonoBatch (a routine within SonoBat) included 

silver-haired bats and a single canyon bat. In addition to the calls classified by SonoBatch, the April 23 

transect run had two obvious silver-haired bats and another possible canyon bat. Likewise, the April 24 

run included six apparent silver-haired bats calls that were not classified by SonoBatch.

Visual Searches for Bat Roosts.—In addition to the acoustic surveys, an observer (T. Manning) 

spent some time searching for likely bat roosts at Columbia NWR in April 2012. Visual searches were 

conducted near Lower Crab Creek, Shiner Lake, and Blythe Lake by searching at the base of rimrock 

cliffs for accumulations of guano and peering into cracks with a flashlight. These searches did not 

provide any evidence that bats used cliffs in these areas.

T. Manning found a single bat roosting under a bridge where McManamon Road crosses Lower 

Crab Creek (NAD83, Zone 11T, 324515E 5196150N) on April 19, 2012. During daylight, T. Manning 

noticed obvious bat guano (fig. 11) in small amounts on the east creek bank, beneath the bridge. Bat 

foraging activity was detected the same evening (April 19, 2012) with a hand-held detector, and one bat 

was found roosting beneath the east side of the bridge. The bat roused and flew immediately in response 

to a flashlight beam. No bats were observed in subsequent visits to the bridge over the next several days 

and nights. 
7 

Discussion

Our winter survey effort was fairly cursory given the small area sampled by each detector 

deployment (less than 50-m radius) relative to the large area of potential habitat, particularly at Hanford 

NM/ Saddle Mountain NWR, and the low probability of detecting bats during winter. Nonetheless, we 

provided evidence of winter bat activity at Columbia NWR. The lack of detections of bats at Hanford 

NM/ Saddle Mountain NWR during the winter suggest the need for more extensive surveys, as we 

covered only a fraction of the potential habitat for a limited period of time. 

Our acoustic data indicated the presence of canyon bats on Columbia NWR in the winter. 

Canyon bats have not previously been recorded north of the Columbia River along the OregonWashington State line outside of the breeding season, so our data provide evidence to extend the known 

winter range of this species. However, acoustic detections alone are often insufficient for conclusive 

identification of species presence (Barclay, 1999), so visual identification of this species during the 

winter would be helpful in confirming a range extension. One of the unknown bat species detected in 

winter at Columbia NWR may have been a little brown myotis, although the acoustical data provided 

only weak evidence for this identification because the signature was not conclusive. This species, along 

with at least three other myotis species (California, western small-footed , and Keen’s myotis) are yearround residents in the region. The wintering habits of other myotis species that potentially occur in the 

region, western long-eared, fringed, Yuma, and long-legged myotis are poorly understood. Additional 

study will be necessary to provide a more comprehensive inventory of wintering bats. One approach to 

obtaining such information is to monitor pre-hibernation and pre-migration bat activity by conducting 

surveys in the late summer and autumn to provide a more complete profile of seasonal activity patterns 

for all species that use the refuge.

Two species that were detected in April, California myotis (four detections) and Townsend’s 

big-eared bat (one detection), represented new species records for the MCNWRC. Both species are of 

conservation concern: the California myotis is listed as a State Vulnerable species in Oregon, and the 

Townsend’s big-eared bat is a Federal Species of Concern, as well as a State Candidate species in 

Washington (table 1). Townsend’s big-eared bats are year-round residents in the Pacific Northwest, 

from California to southern British Columbia. Based on hibernation locations on the upper Snake River 

Plain in Idaho (Genter, 1986) and in central Oregon (Dobkin and others, 1995), and our results 

indicating the presence of this species on Columbia NWR as early as mid-April, it seems likely that it 

over-winters on the refuge. Federally Endangered eastern subspecies of the Townsend's big-eared bat, 

Ozark big-eared bat (Corynorhinus townsendii ingens) and Virginia big-eared bat (C. t. virginianus) 

have not yet been documented as afflicted with white-nose syndrome (WNS), but it now occurs 

throughout much of their respective ranges. More surveys to better understand the seasonal distribution 

of Townsend’s big-eared bats on the MCNWRC would aid conservation planning for this special status 

species.
8 

Two bat species and one close relative of a species present at Columbia NWR in April have been 

affected by WNS in eastern North America: big brown bat, little brown myotis, and eastern small-footed 

myotis (closely related to western small-footed myotis). All three species are reported to overwinter in 

the region. Because they may be among the most vulnerable to WNS, more information about the winter 

ecology, habitat use, and roost locations of these species is urgently needed to inform proactive 

management and effectively prioritize key hibernacula for their conservation. Using the locations where 

we recorded activity in both seasons (winter and spring) to deploy bat detectors from September through 

November may maximize the probability of detecting bats in the off-season. More intensive methods, 

such as tracking individual bats with radio-telemetry (Holland and Wikelski, 2009) and Passive 

Integrated Transponder (PIT) tag technology (see U.S. Geological Survey, 2013) may be helpful in 

locating winter roosts and estimating the numbers of bats using them. 

Of the three survey methods we used, stationary acoustic detectors were the most efficient in 

winter and spring. In the April survey, the average detection rate for transects of 2.1 bat calls/hour was 

considerably lower than recorded by the stationary detectors, which had an average rate of 10 bat 

calls/hour for the same dates. If bat activity was localized near open water, transects that included 

stretches of upland habitat (appendix 3) probably were less likely to encounter bats than stationary 

detectors located in wetland habitat. Visual searches also proved inefficient for finding roosting bats, but 

could be helpful for pinpointing roosts in an area of cliff or rimrock habitat where bat activity has 

already been detected.

References Cited

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Tankersley, R.D., Jr., 2008, Patterns of bat fatalities at wind energy facilities in North America: 

Journal of Wildlife Management, v. 72, no. 1, p. 61–78. 

Barclay, R.M.R., 1999, Bats are not birds—A cautionary note on using echolocation calls to identify 

bats—A Comment: Journal of Mammalogy, v. 80, p. 290–296. 

Bat Conservation Trust, 2007, Bat surveys—Good practice guidelines: London, Bat Conservation Trust, 

accessed May 16, 2013, at http://www.bats.org.uk/pages/batsurveyguide.html. 

Blehert, D.S., Hicks, A.C., Behr, M., Meteyer, C.U., Berlowski-Zier, B.M., Buckles, E.L., Coleman, 

J.T.H., Darling, S.R., Gargas, A., Niver, R., Okoniewski, J.C., Rudd, R.J., and Stone, W.B., 2009, Bat 

white-nose syndrome—An emerging fungal pathogen?: Science, v. 323, no. 5911, p. 227. 

Block, L., 1996, Abandoned mines at Little Pend Oreille National Wildlife Refuge: Moses Lake 

Ecological Services Office, Washington, U.S. Fish and Wildlife Service, 26 p. 

Boyles, J.G., Cryan, P.M., McCracken, G.F., and Kunz, T.H., 2011, Economic importance of bats in 

agriculture: Science, v. 332, p. 41–42. 

Cleveland, C.J., Betke, M., Federico, P., Frank, J.D., Hallam, T.G., Horn, J., Lopez, J.D., McCracken, 

G.F., Medellin, R.A., Moreno-Valdez, A., Sansone, C.G., Westbrook, J.K., and Kunz, T.H., 2006, 

Economic value of the pest control service provided by Brazilian free-tailed bats in south-central 

Texas: Frontiers in Ecology and the Environment, v. 4, p. 238–243. 
9 

Dobkin, D.S., Gettinger, R.D., and Gerdes, M.C., 1995, Springtime movements, roost use, and foraging 

activity of Townsend’s big-eared bat (Plecotus townsendii) in central Oregon: Great Basin Naturalist, 

v. 55, p. 315–321. 

Frick, W.F., Pollock, J.F., Hicks, A.C., Langwig, K.E., Reynolds, D.S., Turner, G.G., Butchkoski, C.M., 

and Kunz, T.H., 2010, An emerging disease causes regional population collapse of a common North 

American bat species: Science, v. 329, p. 679–682. 

Genter, D.L., 1986, Wintering bats of the upper Snake River plain—Occurrence in lava-tube caves: 

Western North American Naturalist, v. 46, p. 241–244. 

Gruver, J.C., and Keinath, D.A., 2006, Townsend’s big-eared bat (Corynorhinus townsendii)—A 

technical conservation assessment: U.S. Department of Agriculture, Forest Service, Rocky Mountain 

Region, accessed December 14, 2012, at 

http://www.fs.fed.us/r2/projects/scp/assessments/townsendsbigearedbat.pdf. 

Holland, R.A., and Wikelski, M., 2009, Studying the migratory behavior of individual bats—Current 

techniques and future directions: Journal of Mammalogy, v. 90, p. 1,324–1,329. 

Jones, G., Jacobs, D.S., Kunz, T.H., Willig, M.R., and Racey, P.A., 2009, Carpe noctem—The 

importance of bats as bioindicators: Endangered Species Research, v. 8, p. 93–115. 

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provided by bats: Annals of the New York Academy of Sciences, v. 1,223, p. 1–38. 

Sherwin, R.E., Altenbach, J.S., and Waldien, D.L., 2009, Managing abandoned mines for bats: Austin, 

Texas, Bat Conservation International, 103 p. 

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Site Final Report—1994–1999: The Nature Conservancy of Washington, prepared in partial 

fulfillment of U.S. Department of Energy Grant Award Number DE-FG06-94RL12858, 179 p. 

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Research News, v. 50, p. 47–53. 

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bats in North America, August 2012: U.S. Fish and Wildlife Service Fact Sheet, accessed May 7, 

2013, at http://whitenosesyndrome.org/sites/default/files/resource/white-nose_fact_sheet_9-2012.pdf. 

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devastating bat disease: website, accessed May 16, 2013, at 

http://whitenosesyndrome.org/resources/map. 
10

Figure 1. Wetlands and rimrock habitat on Columbia National Wildlife Refuge, Washington. 
11

Figure 2. Location of Little Pend Oreille Refuge and Bear Mountain Mine Adit and Shaft, Washington.
12

Figure 3. Bat detector deployment at study sites. (A) Shiner Lake, Columbia National Wildlife Refuge, Washington.

Detector is in the bag on the ground, and microphone is at the end of the horizontal piece of PVC pipe. (B) Bat 

detector deployment at Bear Mountain Mine Shaft, Little Pend Oreille National Wildlife Refuge, Washington. (C) Bat 

detector deployment at Bear Mountain Adit. Little Pend Oreille National Wildlife Refuge, Washington.

A

B

C
13

Figure 4. Bear Mountain Mine at Little Pend Oreille National Wildlife Refuge, May 2012. (A) Mine Shaft with 

standing water. (B) Adit.

. 

A

B
14

Figure 5. Acoustic bat detector deployment locations and number of bat detections (n) at Columbia National 

Wildlife Refuge, Washington, December 2011–January 2012.
15

Figure 6. Location of stationary bat detectors deployed in April 2012, Columbia National Wildlife Refuge, 

Washington. 
16

Figure 7. Species composition of bats detected at Columbia National Wildlife Refuge, Washington, April 17–27, 

2012. Percentages represent relative frequency of calls detected. Species were silver-haired bat (LANO), unknown 

species in the 30-, 40-, and 50-kHz call frequency groups (see table 1), canyon bat (PAHE), western small-footed 

myotis (MYCI), and hoary bat (LACI). “Other” species each comprised less than 1 percent of detected calls: big 

brown bat, little brown myotis, Yuma myotis, California myotis, western long-eared myotis, pallid bat, and 

Townsend’s big-eared bat.

LANO 

44%

30k

26%

40k

13%

PAHE 

6%

MYCI

4%

50k

3%

LACI

1%

other

3%
17

0

5

10

15

20

25

30

35

40

4/17 4/18 4/19 4/20 4/21 4/22 4/23 4/24 4/25 4/26

Figure 8. Index of bat activity (number of bats calls per hour) by date at Columbia National Wildlife Refuge, 

Washington, April 2012.

Figure 9. Average, minimum, and maximum nighttime temperatures (°F) on dates of bat detector deployments, 

Columbia National Wildlife Refuge, Washington, April 2012. 

20 

30 

40 

50 

60 

70 

80 

ave

min

max
18

0

100

200

300

400

500

600

700

800

900

1000

20:00 21:00 22:00 23:00 00:00 01:00 02:00 03:00 04:00 05:00

Total Bat Calls

Figure 10. Total number of bat calls detected as a function of time of night, Columbia National Wildlife Refuge, 

Washington, April 17–27, 2012.
19

Figure 11. Bat guano found under bridge where McManamon Road crosses Lower Crab Creek, Columbia National 

Wildlife Refuge, Washington.
20

Table 1. Names, call frequency groupings, and conservation status of bat species that potentially occur on refuges 

of the Mid-Columbia National Wildlife Refuge Complex, Washington. 

[Species of concern are those whose conservation status is of concern to the U.S. Fish and Wildlife Service, but more 

information is needed. kHz, kilohertz; OR, Oregon; WA, Washington]

Common name Scientific name Code

Call 

group Conservation status

Big brown bat Eptesicus fuscus EPFU 30 kHz None assigned

California 

myotis Myotis californicus MYCA 50 kHz OR: Sensitive—Vulnerable

Canyon bat Parastrellus hesperus PAHE 50 kHz WA: State monitored

Fringed myotis Myotis thysanodes MYTH 30 kHz

OR: Sensitive—Vulnerable; WA: State 

monitored

Hoary bat Lasiurus cinereus LACI 30 kHz OR: Sensitive—Vulnerable

Keen's myotis Myotis keenii MYKE WA: State candidate

Little brown 

yotis Myotis lucifugus MYLU 40 kHz None assigned

Long-legged 

myotis Myotis volans MYVO 40 kHz

OR: Sensitive—Vulnerable; WA: State 

monitored

Pallid bat Antrozous pallidus ANPA 30 kHz

OR: Sensitive—Vulnerable; WA: State 

monitored

Red bat Lasiurus blossevillii LABL 40 kHz WA: State monitored

Silver-haired bat 

Lasionycteris 

noctivagans LANO 30 kHz OR: Sensitive—Vulnerable

Spotted bat Euderma maculatum EUMA 10 kHz

OR: Sensitive—Vulnerable; WA: State 

monitored

Townsend's bigeared batCorynorhinus 

townsendii COTO 30 kHz

Federal: Species of Concern1; OR: 

Sensitive—Critical; WA: State candidate

Western longeared myotis Myotis evotis MYEV 30 kHz WA: State monitored

Western smallfooted myotis Myotis ciliolabrum MYCI 40 kHz WA: State monitored

Yuma myotis Myotis yumanensis MYYU 50 kHz None assigned

Table 2. Dates, times, coordinates, and results of winter driving transects to detect bats at Columbia National 

Wildlife Refuge, Washington. 

Date Start time End time Start UTM E Start UTM N End UTM E End UTM N Bat detections

12/13/2011 16:13 17:56 332768 5198888 331075 5200445 None

12/14/2011 15:31 17:59 330194 5201664 331084 5200349 None

12/20/2011 15:33 17:48 329632 5198407 328324 5201981 Possible

12/21/2011 15:44 18:15 325422 5196943 329285 5197591 None

12/22/2011 16:38 18:02 296206 5148899 286274 5151408 None

12/28/2011 15:54 18:18 327533 5193961 329307 5195369 None

1/10/2012 16:02 17:40 325431 5203102 324247 5204350 None

1/11/2012 16:00 18:20 329624 5200220 332127 5198515 Possible

1/12/2012 16:00 18:29 302739 5174448 302995 5178752 None
21

Table 3. Total number of bats by species or call frequency group and detection rates (average calls/hour; based on 

5 s recording length) at the Bear Mountain Shaft, May 9–15, 2012.

Species Number of 

detections

Detection 

rate

Bat species Western long-eared myotis 71 2.90

Silver-haired bat 10 0.41

California myotis 5 0.20

Western small-footed myotis 1 0.04

Little brown myotis 1 0.04

Yuma myotis 1 0.04

Unknown bat spp. 31 1.27

Species group 40 kHz 53 2.16

30 kHz 43 1.76

Myo30 kHz 21 0.86

50 kHz 12 0.49

Site total 216 10.08

Table 4. Bat species, and weather conditions at times of bat detections, December 2011–January 2012, Columbia 

National Wildlife Refuge. 

 [Climate data provided courtesy of Washington State University’s AgWeatherNet©. Weather data represent conditions at 

time of bat detections, +/- 15 minutes] 

 

Date Species Time

Temp 

(oF)

Relative 

humidity

(percent)

Wind 

(mph)

12/05/2011 Canyon bat 17:53 30.1 77.1 3.2

12/27/2011 Canyon bat 18:48 43.7 76.5 8.9

01/11/2012 Unknown 17:53 25.6 62.9 4.3

01/12/2012 Unknown 17:33 25.5 77.2 2.4

01/12/2012 Unknown 17:51 26.1 75.2 2.3

01/14/2012 Unknown 19:49 29.7 64 9

01/14/2012 Canyon bat 19:56 29.6 65.7 13.1

01/17/2012 Myotis sp. 17:25 32.8 62.6 9.4

01/17/2012 Unknown 17:28 32.8 62.6 9.4

Averages for weather: 30.66 69.31 6.89
22

Table 5. Total detection and detection rates (average calls/hour; based on 5 s recording length) of bats by species 

at seven sites on Columbia National Wildlife Refuge, Washington, April 17–27, 2012. 

[Species are sorted by frequency of detection, from most to least] 

Blythe 

Lake

Crescent 

Lake

Goldeneye 

Lake

Lower 

Crab 

Creek

Lower 

Hampton 

Lake

Lowest 

Crab 

Creek

Shiner 

Lake

Species 

totals

Silver-haired bat 0 341 359 175 61 196 131 1,263

30KhZ group 0 196 248 153 15 30 85 727

40KhZ group 1 14 76 60 28 102 89 370

Canyon bat 0 0 5 11 2 101 41 160

Western small-footed 

myotis 0 6 34 8 23 16 33 120

50kHz group 0 0 7 13 3 31 16 70

Hoary bat 0 0 18 10 2 0 8 38

Unknown bat spp. 0 1 13 11 2 11 0 38

Big brown bat 0 0 20 6 0 1 3 30

Yuma myotis 0 0 4 8 0 0 2 14

Little brown myotis 0 1 4 0 0 1 2 8

California myotis 0 0 0 0 1 2 1 4

Western long-eared 

myotis 0 0 0 0 0 1 1 2

Pallid bat 0 0 0 0 0 0 1 1

Townsend's big-eared 

bat 0 0 0 0 0 0 1 1

Site totals 1 559 788 455 137 492 414 2,846

Bats/hour 0.1 26.0 18.1 8.3 2.5 15.2 7.4 10.4

Table 6. Locations, dates, times, and results of acoustic transect surveys for bats in Columbia National Wildlife 

Refuge, Washington, April 2012. 

Transect # Date

Start 

Time

Total 

time

Start 

UTM E

Start 

UTM N

End 

UTM E

End UTM 

N Weather Bats

Transect 1 4/21 20:17 0:38 328398 5205596 324293 5197084

Clear, still, 

54°F, new 

moon. 40 kHz

Transect 1 4/23 20:21 0:37 328398 5205596 324293 5197084 72°F, cloudy.

1 PAHE, 

2 LANO

Transect 1 

in reverse 4/24 20:22 0:40 324293 5197084 328398 5205596

Clear, still, 

56°F; young 

moon. 1 LANO

Transect 2 4/25 20:23 0:38 324251 5204632 332783 5198882

Cloudy, 

breezy, 55°F. Noise

Transect 3 4/26 20:25 0:20 328250 5197417 332804 5198861 Windy, 45°F. 1 LANO
23

Appendix 1. Dates and Locations of Deployments of Acoustic Bat Detectors at 

Columbia, Hanford NM/Saddle Mountain, and Little Pend Oreille National Wildlife 

Refuges, Winter 2011–2012

Date deployed Date retrieved

Time 

deployed Refuge Site name

UTM

(Zone 11, NAD 83)

Easting Northing

10/04/2011 10/17/2011 12 days LPO Bear Mountain Shaft 446549 5364250

10/17/2011 10/28/2011 2 daysa LPO Bear Mountain Adit 446473 5364420

12/01/2011 12/08/2011 7 days Columbia 330901 5200355

12/01/2011 12/08/2011 7 days Columbia 330932 5201285

12/08/2011 12/14/2011 6 days Columbia 330940 5200765

12/08/2011 12/14/2011 6 days Columbia 330823 5201719

12/14/2011 12/21/2011 7 days Columbia 330624 5202579

12/14/2011 12/21/2011 7 days Columbia 329996 5201734

12/21/2011 12/28/2011 7 days Columbia 324926 5196639

12/21/2011 12/28/2011 7 days Columbia 325422 5196943

12/28/2011 01/06/2012 9 days Columbia 329259 5197653

12/28/2011 01/06/2012 9 days Columbia 328850 5197528

01/06/2012 01/11/2012 5 days Columbia 328427 5194104

01/06/2012 01/11/2012 5 days Columbia 328825 5194664

01/11/2012 01/19/2012 8 days Columbia 326134 5194247

01/11/2012 01/26/2012 15 days Columbia 326059 5203272

01/20/2012 01/25/2012 4 days Columbia 330047 5199324

12/16/2011 12/22/2011 6 days Hanford Rattlesnake Springs 292339 5153702

12/16/2011 12/22/2011 6 days Hanford Sniveley Homestead 291515 5147919

12/22/2011 12/29/2011 7 days Hanford Bobcat 295965 5147525

12/22/2011 12/29/2011 7 days Hanford Sniveley Canyon 291026 5148719

12/29/2011 01/05/2012 7 days Hanford 312420 5139464

12/29/2011 01/05/2012 7 days Hanford 294070 5153687

01/05/2012 01/12/2012 7 days Hanford Saddle 313341 5185075

01/05/2012 01/12/2012 7 days Hanford Canal Bridge 311178 5182141

01/12/2012 01/18/2012 6 days Hanford 303090 5173178

01/12/2012 01/18/2012 6 days Hanford 306405 5177396

01/20/2012 01/26/2012 6 days Hanford 318796 5171631

01/20/2012 01/26/2012 6 days Hanford 326437 5153106

04/17/2012 04/18/2012 11 h 39 min Columbia Shiner Lake 325931 5194309

04/18/2012 04/19/2012 11 h 8 min Columbia Shiner Lake 325931 5194309

04/19/2012 04/20/2012 11 h 5 min Columbia Shiner Lake 325931 5194309

04/20/2012 04/21/2012 11 h 2 min Columbia Shiner Lake 325931 5194309

04/21/2012 04/22/2012 10 h 59 min Columbia Shiner Lake 325931 5194309

04/22/2012 04/23/2012 10 h 55 min Columbia Goldeneye Lake 327771 5204246

04/23/2012 04/24/2012 10 h 53 min Columbia Goldeneye Lake 327771 5204246

04/24/2012 04/25/2012 10 h 50 min Columbia Goldeneye Lake 327771 5204246

04/25/2012 04/26/2012 10 h 47 min Columbia Goldeneye Lake 327771 5204246

04/26/2012 04/27/2012 malfunction Columbia Goldeneye Lake 327771 5204246

04/19/2012 04/20/2012 11 h 5 min Columbia Lower Crab Creek 325422 5196943

04/20/2012 04/21/2012 11 h 2 min Columbia Lower Crab Creek 325422 5196943

04/21/2012 04/22/2012 10 h 59 min Columbia Lower Crab Creek 325422 5196943

04/22/2012 04/23/2012 10 h 55 min Columbia Lower Crab Creek 325422 5196943

04/23/2012 04/24/2012 10 h 53 min Columbia Lower Crab Creek 325422 5196943

04/24/2012 04/25/2012 10 h 50 min Columbia Lowest Crab Creek 321335 5189756
24

Date deployed Date retrieved

Time 

deployed Refuge Site name

UTM

(Zone 11, NAD 83)

04/25/2012 04/26/2012 10 h 47 min Columbia Lowest Crab Creek 321335 5189756

04/26/2012 04/27/2012 10 h 44 min Columbia Lowest Crab Creek 321335 5189756

04/19/2012 04/20/2012 11 h 0 min Columbia Blythe Lake 325445 5203011

04/19/2012 04/20/2012 11 h 5 min Columbia Lower Hampton Lake 330716 5199444

04/20/2012 04/21/2012 11 h 2 min Columbia Lower Hampton Lake 330716 5199444

04/21/2012 04/22/2012 10 h 59 min Columbia Lower Hampton Lake 330716 5199444

04/22/2012 04/23/2012 10 h 55 min Columbia Lower Hampton Lake 330716 5199444

04/23/2012 04/24/2012 10 h 53 min Columbia Lower Hampton Lake 330716 5199444

04/24/2012 04/25/2012 malfunction Columbia Crescent Lake 334306 5198891

04/25/2012 04/26/2012 10 h 47 min Columbia Crescent Lake 334306 5198891

04/26/2012 04/27/2012 10 h 44 min Columbia Crescent Lake 334306 5198891

05/9/2012 05/17/2012 7 days LPO Bear Mountain Shaft 446549 5364250

05/9/2012 05/17/2012 7 days LPO Bear Mountain Adit 446473 5364420

a Data cards filled with noise on the third night of deployment effectively terminating data collection.
25

Appendix 2. Recording and Displaying Bat Acoustic Transects

Documentation and instruction on how to produce displayable transect files from GPS track data 

and bat call detection files are not readily available from the developer of the MyotisoftTM programs. 

We documented the following protocol to make it easier for future users. These directions pertain 

specifically to GarminTM and DeLorme GPS instruments, and SonoBatTM 3.05 acoustic software. 

To successfully record all data needed for a displayable transect:

1. Be sure you know how your particular GPS records track data, and how to download the track 

data, including time data for each trackpoint. Without time data for each individual trackpoint, 

Myotisoft Transect© or TransectPro© software cannot produce a transect file to display. Also, 

be sure that it is possible to convert a GPS track file to a GPX file, because that’s the format 

used by Myotisoft software. 

For instance, with a GarminTM GPSmap 60, the instrument is by default set to record a waypoint 

on the track every 100 meters. By changing the set-up, it is possible to record one waypoint per 

some-given-time-interval (we used 10 s). This is apparently the only way to get time data for a 

track. At the completion of each transect, the “active log” must be downloaded from that track to 

some outside data storage. This “active log” file appears to be the only place where the time data 

are stored, and the active log is temporary, that is, it gets replaced in the GPS (that is, lost) when 

a new track is started. Files saved as tracks alone, without the active log, will not include time 

data. Later, the downloaded active log can be opened on a computer with the GarminTM 

software or EasyGPS software and saved as a GPX file with extension “.gpx”. The GPX file is 

input for the Myotisoft program. 

The procedure is different with a DeLorme Earthmate PN40 GPS. In this case, it appears the 

default is to create tracks with time data included, and the file saved as a “track” apparently has 

the time data needed to produce a transect display. That is, there is no additional “active log;” 

thus, the track can simply be saved within the GPS, and the track can be downloaded to a 

computer later (using the DeLorme software supplied with the instrument) and exported as a 

GPX file.

2. Before starting a transect, make sure that the GPS and bat detector are synchronized as closely as 

possible (generally within 2 s error), so that accurate locations of bat calls are recorded. 

3. Use a standardized transect datasheet and checklist to make sure no essential data are omitted

and that all pertinent data are recorded, such as temperature, weather conditions, start and stop 

times, start and stop locations, route details, etc.

4. Remember to save and download GPS and call data at the end of each transect. Remember that 

with some GPS instruments it is necessary to download the “active log” after each transect to get 

usable time data that is synchronized with position data.
26

5. We recommend testing these procedures before running a transect to collect real data, to make 

sure that 

A) track points are associated with time data, 

B) it is possible to save and/or download trackpoints, and 

C) it is possible to convert or export to the GPX format. 

To display transect data using the Myotisoft Transect© or TransectPro©: 

1. To get recorded bat acoustic data ready for the Myotisoft program, run the SonoBatTM File 

Attributer to scrub out the majority of the non-bat noise files, then run the SonoBatTM Suite for 

the appropriate geographic region in batch mode (SonoBatch) to make preliminary 

classifications of the bat call files.

Be sure to set the batch processor to “append spp. to filenames” (button at bottom right of 

SonoBatch window). Doing this will attach a standard four-letter species acronym to each file of 

sufficient quality to classify. For instance,

“CMB_Transect 1-24Apr12-20,40,58” 

becomes

“CMB_Transect 1-24Apr12-20,40,58-Lano”

This signifies that the call file has been classified as a silver-haired bat (Lasionycteris 

noctivagans). The Myotisoft program will need this to label bat calls on the final transect 

display. 

Note that this extra label is attached to the actual batcall files in the transect data, not to the text 

file that results from the SonoBatch routine; the text file is NOT used in the Myotisoft program.

Also, be aware that the scrubbing and classifying processes described in this step may take many 

hours of processing, depending on computer speed and the number of call files. Although much 

of this process is automated by SonoBatTM and takes little input from the user, the batch 

classification of bat call files by SonoBatTM is preliminary and should be verified by an expert.

2. The GPX file should be checked to make sure it includes time data and geographic coordinates 

also check bat call files to verify that at least some have species acronyms attached. Start 

Myotisoft Transect© (to display transects using Google EarthTM ) or TransectPro© (to display 

transects using ArcGIS) and follow the prompts to tell the program where GPX and batcall data 

are to be stored, and where results files are to be saved. 
27

3. If no error message is displayed, the transect and results should be displayable. Look for a file 

with extension .kmz (for Transect to use in Google EarthTM) or .shp (for TransectPro© to use in 

ArcGIS) in the location specified for results output. To view a transect on a computer loaded 

with Google EarthTM, simply double-click the file icon and it should open Google EarthTM and 

display the transect automatically. Bat icons are displayed at the locations where acoustic files 

were recorded. Classified calls are labeled with their species acronym, and noise files or poor bat 

call files will display as “Unknown.” The “Unknown” labels can be turned off (unchecked) 

using the sidebar in Google EarthTM. 
28

Appendix 3. Bat Survey Transect Routes and Bats Detected, Columbia National Wildlife Refuge, 

Washington, April 2012

Bat Survey Transect 1 at Columbia National Wildlife Refuge, April 23, 2012. One canyon bat (PAHE; Parastrellus hesperus) and two 

silver-haired bats (LANO; Lasionycteris noctivagans) were detected.
29

Bat Survey Transect 2 at Columbia National Wildlife Refuge, April 25, 2012. No bats were detected.
30

 Bat Survey Transect 3 at Columbia National Wildlife Refuge, April 26, 2012. One silver-haired bat (LANO; Lasionycteris 

noctivagans) was detected.
Publishing support provided by the U.S. Geological Survey

Publishing Network, Tacoma Publishing Service Center

For more information concerning the research in this report, contact the

Director, Forest and Rangeland Ecosystem Science Center,

U.S. Geological Survey, 777 NW 9th Street

Corvallis, Oregon 97330

http://fresc.usgs.gov
Printed on recycled paper

Hagar and others— Survey of Bats on the Mid-Columbia River National Wildlife Refuge Complex and Little Pend Oreille, Wash.—Open-File Report 2013-1120