Byron Flora and Fauna Study 1999 - Byron Shire Council

BYRON FLORA AND FAUNA STUDY, 1999
Appendix 9
A call survey of bats of Byron Shire, NSW
H Parnaby, PO Box 2359, Coffs Harbour 2450
September 1998.
Report prepared for Landmark Ecological Services.
INTRODUCTION
A survey of bats was undertaken at 52 sites within Byron Shire during the period 6 April - 7 May, 1998. The
survey relied primarily on detection of calls using the Anabat call detection system, and was designed to
target species considered to be of particular conservation concern, and/or that were known from few
records from the region. The survey targeted a subset of those listed as Vulnerable on Schedule 2 of the
NSW Threatened Species Conservation Act, 1995 and are listed in Table 1.
Table 1 Priority species targeted during the survey
First priority species
Yellow-bellied Sheathtail-bat
Beccari’s Freetail-bat
Eastern Freetail-bat
Second priority species
Golden-tipped Bat
Eastern False Pipistrelle
Eastern Tube-nosed Bat
Hoary Wattled Bat
Eastern Cave Bat
Large-eared Pied Bat
SURVEY METHODS
Surveys were undertaken using hand held bat detectors, and calls analysed using the Anabat5 call detection
system and software (Titley Electronics, Ballina). The duration of surveys per site varied from 10 to 60
minutes, depending on levels of activity. Manually operated surveys were used rather than automated recording
methods, as the operator was able to track the bat and thereby obtain better quality call sequences of longer
duration, thereby increasing the ability to obtain species identifications from calls.
Bat species recognition is not always possible from echolocation calls. Some call sequences are too distant
or indistinct, or too brief to enable species identification. The variation in call types exhibited by some
species is still not properly defined and calls of some species are very similar and cannot be reliably
distinguished for some species. Consequently, three categories of confidence in species identification are
recognised (Parnaby 1992):
Definite identification (X): species identity not in doubt;
Probable identification (P): species identification most likely, but a low probability of confusion
with species with similar call types;
Possible identification (): call characteristics are comparable with the species, but a reasonable
probability of confusion with one or more similar species.
Call surveys were made at a total of 52 sites. Sites less than about 100 m apart were designated as subsites,
unless significantly different habitat was sampled. Some sites were resampled, and the total number of
censuses was 63, for a total duration of approximately 30 hours. Site location, date, start time and duration
of surveys at each site are given in Table 3.
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