Today is the start of the nominal ‘low’ period for this 8-week exercise, the framework of which is repeated below.
Martin has helpfully provided summary data for 8 of the 10 species for 28 years of the GBS – the other 2 not being recorded in gardens in the 8-week period. Of itself, this table seems to raise some interesting points, but enough of that for now. This exercise is of course not limited to GBS sites and extends to the whole COG area of interest.
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Full Period |
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RAOU_number |
New_name |
Total # birds |
# sites |
A |
F% |
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338 |
Fan-tailed Cuckoo |
25 |
22 |
0.0021 |
1.3 |
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401 |
Rufous Whistler |
410 |
364 |
0.0344 |
20.8 |
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424 |
Black-faced Cuckoo-shrike |
2287 |
1586 |
0.1916 |
90.7 |
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453 |
White-throated Gerygone |
13 |
10 |
0.0011 |
0.6 |
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463 |
Western Gerygone |
12 |
9 |
0.0010 |
0.5 |
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547 |
Dusky Woodswallow |
175 |
15 |
0.0147 |
0.9 |
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645 |
Noisy Friarbird |
306 |
139 |
0.0256 |
8.0 |
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671 |
Olive-backed Oriole |
20 |
20 |
0.0017 |
1.1 |
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Site weeks |
sites active |
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Denominators |
11934 |
1748 |
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Shaun Bagley has pointed out that some of the subject birds might be not absent but silent, which is part of the challenge. A silent reed-warbler skulking somewhere in a reed-bed (which the ACT atlas suggests one or two might do) would be quite a find.
Previous message:
From: Geoffrey Dabb [
Sent: Wednesday, 2 June 2010 11:06 AM
To:
Subject: Festival of the Straggler
Putting aside those species that leave the Canberra area altogether, we all know about those species that become a bit scarce in the local area in the Winter months. July is the low month for several of those species. Actually the lowest period might be something more like 20 June – 20 July. This year let’s take a closer look at the 8 weeks ending on 31 July, starting this Sunday 6 June. There are signs that with the wet Autumn more food might be around this Winter.
It’s a bit arbitrary, but these are the 10 species I suggest are of main interest in this regard:
Fan-tailed Cuckoo
Black-faced Cuckoo-shrike
Australian Reed-Warbler
Rufous Whistler
Rufous Songlark
Western Gerygone
White-throated Gerygone
Noisy Friarbird
Olive-backed Oriole
Dusky Woodswallow
None impossible, some more likely than others.
If you come across any of those 10 species in the ACT/COG area 6 June to 31 July. I would be very interested to get a report of it (with numbers) with a view to collating the results. You could send a report to the chatline or to me directly.
