. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 22 GEORGE DECOURSEY AM) PATRICIA J. DECOURSEY measured with a I .ange Luxmeter. Simple recording methods were devised for counting and tabulating data i^ithoui /////;/ or noise disturbance to the bats. Observations Jn spite of severe limitations, tic-Id studies offer possibilities for further insight into the problem of environment-sampling by the bats. Due to conspicuous colonial habits, bats are more suitable for surveillance than most nocturnal species, and havi' been the object of many observations. Emergence of bats fro
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 22 GEORGE DECOURSEY AM) PATRICIA J. DECOURSEY measured with a I .ange Luxmeter. Simple recording methods were devised for counting and tabulating data i^ithoui /////;/ or noise disturbance to the bats. Observations Jn spite of severe limitations, tic-Id studies offer possibilities for further insight into the problem of environment-sampling by the bats. Due to conspicuous colonial habits, bats are more suitable for surveillance than most nocturnal species, and havi' been the object of many observations. Emergence of bats from roosting places usually takes place at dusk (Allison, 1937; Church. 1957; Eisentraut, 1952; Moebus, unpublished data; Schwassmann, personal communication; Twente, 1955; Venables, 1953), often correlated with a small range of light intensities (Twente, 22^00- co cr O LJ 5. 20 00 17 21 FIGURE 6. Summary for the Wendelsheim colony \vith white central /one indicating tin- flight time (exit count rising above four hats/2 minutes to count dropping hel\\ I'mir hats/2 minutes) for the normally lighted loft at left, crosshatched, and for the darkened church at right, black. Symbols: o average exit time on clear days, and • on cloudy days, x for outdoor light intensity of lux. 1955; \ enables, 1953), but the darkness of a total eclipse during daytime did not evoke activity (Krzanowski, 195(>). Exit flight times roughly parallel the time of sunset throughout the summer (Church, 1('57; Moebus, unpublished datai. thus implicating light as the chief synchronizer, in spite l the poorly developed vision of bats. The \\Vndelsheiin colony was also strictly nocturnal. After remaining rela- tivelv quietly in Room 1 or 2 during the day, the bats departed rapidlv from the church about one half hour alter sunset. The flight rate rose in a tew minutes to. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
