G'day Bird Enthusiasts
Stephen Garnett has just informed me that the WTNT has been declared
Vulnerable. Thank you all for helping to collect the data to make
this declaration. Here are the details:
White-throated Needletail Hirundapus caudacutus caudacutus
Listed in Australia as Vulnerable A2b+3b+4b
Evidence has been presented in Tarburton (2014) that there has been a
decline in the migratory subspecies exceeding 30%. This decline has
been corroborated using a number of independent data sources. It has
been attributed primarily to habitat loss in the breeding grounds.
Only Criterion A can apply as the subspecies occurs over too large an
area for Criterion B, is too numerous for Criteria C and D and has
not been modelled in a manner suitable for Criterion E. The rapid
decline has been occurring over a long period so this probably counts
as a correction to the 2010 Action Plan, but listing probably could
not be justified for 1992 or 2000. At this stage only criteria A2b+3b
+4b apply - declines of 30-50% in 3 generations (25.5 years) based on
an index of abundance appropriate to the taxon. The suggestion that
the decline is caused by habitat loss, though likely, is still a
little speculative to warrant A2c.
As a result of sending my last Annual report on WTNT, Alastair Smith
has requested that I mention how many of my records come from eBird,
so to be fair I have dug out all group resources and hope I have not
missed any. These are the number of observations from each source –
and of course there are many sightings reported in more than one
location. Sources are (in alphabetical order):
animalfineartbycheryl-ann.com (1), Bellingen Birders per Richard
Jordan (12), Billandsuedownunder.blogspot.com.au/ (1), Biocache
(10), Birding-Aus (44), BLAtlas (112), Birdlife Goldcoast per John
Allsop (11), BL East Gippsland per Chris Healey (50), Birding NSW per
Tom Wilson (1), Birdline & Birdline rejects thankfully sent on to me
(118), Birds WA (1), Blue Mtns B.O. -Mark Ley (31), BQ per Brian
Tynan (2), Cairns Birds (3), Canberra Birds/COG per Mark Clayton
(17), Direct (1752), e-Bird (767), Eremaea Birdline (126), FSCB-
Barbara Jones (36), geoffpark.wordpress.com (1), Hunterbirding (40),
per other intermediary (172), The Twitcher per Alan Morris (21),
Please have a great Swift season, & I look forward to receiving this
season's results.
Mike
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Michael Tarburton
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