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Recently there has been some discussion about lower
reporting rates of some species in the present Atlas than in the first
Atlas. Tabulated below are reporting rates for Little Button-quail for the
9 one degree squares centred on Alice Springs. This is a parochial
approach because I prefer to talk about areas that I know a little about.
It can be seen that in Atlas 1 LBQ were reported in
only 3 of the squares, while in Atlas 2 they have been reported in all 9.
The most likely explanation for this is that the
probability of seeing LBQ is directly proportional to the distance walked across
grassland. Beating around 2 ha search areas is a good way to find
them. They are generally not seen while travelling on roads, but may been
seen on little-used and overgrown bush tracks. The high reporting rate in
22/133 is probably a reflection of a high proportion of 2 ha searches in this
square. The low reporting rates for 23/132 and 23/134 are a reflection of
the fact that most surveys for these have come from a few popular tourist spots
that are not good LBQ habitat.
A second possible factor is that most observers for
Atlas1 would have been using the Slater 1st edition field guide. This does
not show how to distinguish LBQ and Stubble Quail as they fly away from the
observer when flushed. Many Atlassers may not have been able to
distinguish them with confidence.
The final conclusion is that comparisons between
Atlas1 and Atlas2 range from difficult to impossible.
Robert Read
Alice Springs
|
|
|
Atlas 1 |
Atlas 2 |
|
|
Lat |
Long |
No surveys |
Surveys with LBQ |
No surveys |
Surveys with LBQ |
% |
|
22 |
132 |
26-50 |
0 |
71 |
6 |
8% |
|
22 |
133 |
26-50 |
0 |
170 |
38 |
22% |
|
22 |
134 |
6-25 |
<10% |
45 |
5 |
11% |
|
23 |
132 |
>50 |
0 |
118 |
2 |
2% |
|
23 |
133 |
>50 |
>10% |
1364 |
132 |
10% |
|
23 |
134 |
>50 |
0 |
113 |
3 |
3% |
|
24 |
132 |
>50 |
0 |
27 |
1 |
4% |
|
24 |
133 |
>50 |
>10% |
157 |
17 |
11% |
|
24 |
134 |
26-50 |
0 |
94 |
6 |
6% |
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