Open Access
How to translate text using browser tools
1 December 2003 Another Quantitative Measure of Bat Species Activity and Sampling Intensity Considerations for the Design of Ultrasonic Monitoring Studies
Hugh G. Broders
Author Affiliations +
Abstract

To date, much of the research that has used ultrasonic detectors as a tool to address questions on the spatial and temporal distribution of bat species activity have been limited by the lack of a reliable and quantifiable unit of activity, and a poor understanding of sampling intensity required to accurately assess site-specific activity levels. Here it is demonstrated that file size (i.e., bytes) of Anabat-recorded echolocation sequences of the little brown bat (Myotis lucifugus) was highly correlated with the number of calls, and was easily determined, and therefore represents a reliable and quantifiable unit of echolocation activity. Additionally, it is shown that accurate quantification of a site-specific magnitude of M. lucifugus activity may not be possible, even with a sampling intensity of up to 20 nights. As a result, ultrasonic monitoring studies must be designed to minimize the effects of the high variability in bat species activity at a site among nights.

LITERATURE CITED

1.

E. R. Britzke , K. L. Murray , B. M. Hadley , and L. W. Robbins . 1999. Measuring bat activity with the Anabat II system. Bat Research News, 40: 1–5. Google Scholar

2.

H. G. Broders, C. S. Findlay, and L. Zheng . In press. The effects of clutter on echolocation call structure of Myotis septentrionalis and M. lucifugus. Journal of Mammalogy. Google Scholar

3.

J. P. Hayes 1997. Temporal variation in activity of bats and the design of echolocation monitoring studies. Journal of Mammalogy, 78: 514–524. Google Scholar

4.

J. P. Hayes 2000. Assumptions and practical considerations in the design and interpretation of echolocation-monitoring studies. Acta Chiropterologica, 2: 225–236. Google Scholar

5.

J. P. Hayes , and M. D. Adam . 1996. The influence of logging riparian areas on habitat utilization by bats in western Oregon. Pp. 228–237, in Bats and Forests Symposium ( R. M. R. Barclay and R. M. Brigham , eds.). British Columbia Ministry of Forests, Victoria, British Columbia, 292 pp. Google Scholar

6.

K. R. Hecker , and R. M. Brigham . 1999. Does moonlight change vertical stratification of activity by forest-dwelling insectivorous bats. Journal of Mammalogy, 80: 1196–1201. Google Scholar

7.

T. S. Jung , I. D. Thompson , R. D. Titman , and A. P. Applejohn . 1999. Habitat selection by forest bats in relation to mixedwood stand types and structure in central Ontario. Journal of Wildlife Management, 63: 1306–1319. Google Scholar

8.

R. A. Krusic , and C. D. Neefus . 1996. Habitat associations of bat species in the White Mountains National Forest. Pp. 185–198, in Bats and Forests Symposium ( R. M. R. Barclay and R. M. Brigham , eds.). British Columbia Ministry of Forests, Victoria, British Columbia, 292 pp. Google Scholar

9.

R. A. Krusic , M. Yamasaki , C. D. Neefus , and P. J. Pekins . 1996. Bat habitat use in White Mountain National Forest. Journal of Wildlife Management, 60: 625–631. Google Scholar

10.

D. J. Larson , and J. P. Hayes . 2000. Variability in sensitivity of Anabat II bat detectors and a method of calibration. Acta Chiropterologica, 2: 209–213. Google Scholar

11.

Mathsoft . 1999. S-PLUS 2000, Professional Release 2. Seattle, Washington. Google Scholar

12.

B. W. Miller 2001. A method for determining relative activity of free flying bats using a new activity index for acoustic monitoring. Acta Chiropterologica, 3: 93–105. Google Scholar

13.

V. M. Siedman , and C. J. Zabel . 2001. Bat activity along intermittent streams in northwestern California. Journal of Mammalogy, 82: 738–747. Google Scholar

14.

R. R. Sokal , and F. J. Rohlf . 1995. Biometry: the principles and practice of statistics in biological research. W. H. Freeman and Company, New York, 887 pp. Google Scholar

15.

D. W. Thomas 1988. The distribution of bats in different ages of douglas-fir forests. Journal of Wildlife Management, 52: 619–626. Google Scholar

16.

G. S. Zimmerman , and W. E. Glanz . 2000. Habitat use by bats in eastern Maine. Journal of Wildlife Management, 64: 1032–1040. Google Scholar
© Museum and Institute of Zoology PAS
Hugh G. Broders "Another Quantitative Measure of Bat Species Activity and Sampling Intensity Considerations for the Design of Ultrasonic Monitoring Studies," Acta Chiropterologica 5(2), 235-241, (1 December 2003). https://doi.org/10.3161/001.005.0206
Received: 20 May 2003; Accepted: 4 July 2003; Published: 1 December 2003
KEYWORDS
Anabat
echolocation
index
Myotis lucifugus
research design
sampling intensity
Back to Top