Wambo Coal AEMR 2011-2012 - Peabody Energy

An additional species, namely the Western Broad-nosed Bat (Scotorepens balstoni), was
analysed as a ‘Probable’ recording (meaning that the unique call ‘signature’ could not be
definitely assigned to the species) across three separate sites.
3.3 Discussion
3.3.1 Swift Parrot and Regent Honeyeater Winter Surveys
Targeted winter bird surveys for the Swift Parrot and Regent Honeyeater during 2008,
2009, 2010 and 2011 have failed to identify either species. Each year a limited foraging
resource of few eucalypt blossoms during winter was observed, which reduced the
chances of either species migrating to the area. Due to each species highly nomadic
movement patterns, the failure to record either species does not suggest that they could
not occur at Wambo Coal Mine. When years of heavy eucalypt blossom do occur, either
species may occur in response to the presence of an increased foraging resource.
3.3.2 Bird Surveys
The 2011 survey recorded the average number of bird species, when compared to all
other survey seasons, including the Common Bronzewing (Phaps chalcoptera) and Varied
Sittella (Daphoenositta chrysoptera) (see Plate 1 and 2). Nine of the 26 sites recorded the
highest number of bird species compared to any other year. Conversely six sites recorded
their lowest species richness score since 2008, however just two of these sites have
recorded decreasing numbers of bird species in the four consecutive years of data. It may
be however that this decline is due to variation from a combination of a number of factors,
as opposed to localised population decreases in specific bird species. The variation in the
number of species recorded each year may partly be attributed to any of the below
factors:
• Natural variability in the number of bird species at a site during any 20 minute period;
• Variability in seasonal conditions across the four years of sampling;
• Variation in the number of sites sampled each year (ranged from 22 to 26);
• Variability in the time of year of surveys;
• Variability in the time of day of surveys; and
• Observer bias. Likely variation in the skill level of observers across the four years has
likely resulted in an unknown level of variability in the total number of species
recorded.
The variability in the number of bird species recorded at each site is likely due to a
combination of the above factors and as such is a result of variability inherent in
undertaking a single brief survey at each site.
2011 Annual Ecological Monitoring Report, Final Report, May 2012 Page 24