Hello Benj,
I was checking mail on the server during lunch time. I am taking the option to
reply from my desk computer at the ANBG.
With the following advice:
To have 3 members of either swift species together in Canberra in early May
would be truly astonishing. Individual late ones are a rarity but 3?
You tell us they were "Nowhere near big enough for hobby or peregrine." However
the difference in size between a White-throated Needletail and an Australian
Hobby is small, only a few cm and they were clearly not close to you. So at
that distance and against the sky, it would be difficult for anyone to make
that judgement of size.
Last week I watched three Australian Hobbies flying in identical behaviour to
what you described. They were going over the main entrance lawn in front of the
Hudson's cafe at ANBG, (I was just out of the office maybe lunchtime, I don't
recall in front of the cafe), they were flying very high doing loops around
each other, towards the top of Black Mountain and calling a lot. I watched them
for a minute or two and have no doubt of my ID. I detected and identified them
from the call first and then watched till then they disappeared towards Black
Mountain. I suspect they are an adult pair with one young (a little bit late in
the year for that but as it is a good wet year, that is not so odd).
Quite apart from what I saw, what you describe in appearance and calls fits
Australian Hobby perfectly, with nothing contrary to that id, except your idea
of size, which is at best problematic. The bit about "tail fanned widely into
a broad slight V and dark chested with white diluted washy indistinct
striations, no white seen on belly or rump" does not fit either swift.
The chasing behaviour of swifts that you describe occurs at their breeding
grounds and occassionally here when large flocks indulge in what appears to be
pre courting displays. I have only ever seen that once and wrote it up in CBN
about 25 years ago. It has only rarely been described in Australia and gets a
few mentions in HANZAB (can't recall if mine was one of them).
Philip Veerman
Office Manager
Australian Network for Plant Conservation Inc
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> On Saturday at the Botanic gardens I came out of the rainforest, heading to
> the Banksia garden, when I heard an unusual call, looking up a huge dark
> cumulus cloud was rapidly heading East through an otherwise clear sunny sky.
> These are the notes I made of the 3 birds that I saw (before I checked my
> Field Guides).
> a) Very high pitched rapid calling- "tewee twee t whin", repeated
> b) Three birds flying around each other in tightish circle, gradually rising,
> with rapid- flapping flight
> c) Birds with swift-like wings, not fat, tail fanned widely into a broad
> slight V
> d) I saw a light throat, dark â??chestâ?? with white diluted washy indistinct
> striations, no white seen on belly or rump.
> e) Black head, wings and tail.
> f) Way larger than swallows or martins, no red, mainly black with little
> white. Nowhere near big enough for hobby or peregrine.
> The three birds were circling towards the south slightly and disappeared from
> view due to the rainforest branches.
> .
> ,
> Initially my impression was Fork-tailed swift, but after checking field
> guides (Morcombe. Simpson and Day. and Slaters et al) and reference books
> (Birds of Canberra Gardens, Complete book of Aust birds) I have changed my
> mind. I guess Iâ??m asking whether anyone else was outside at ~ 2:50pm
> Saturday. Did you see them? Iâ??ve seen fork-tailed swifts only 2 times
> before and WTN about 6 times. Iâ??ve seen plenty of swallows, martins and
> raptors over the past few months though.
> ,
> Here is my reasoning for what I saw/heard, above
> a) I didnâ??t recognise the call. Initially I was looking in the tops of the
> rainforest trees because I thought they were lorikeets (eg as described for
> FTS in most Field guides) after I heard the calls a few times I thought maybe
> swallows (but much louder and stronger), Slater et al mention a hoarse
> rainbow bee-eater (FTS) which is a good description, except it was more
> trill- like.
> B, c) Field guides mention WTN flies very fast, slow turns (as Ive also
> observed), while Simpson and Day mentions â??bat-likeâ?? flight for FTS. All
> field guides show FTS as narrow tailed or forked, with the WTN always with
> square- flat tail.. Only the CBOAB mentions WTN turning sharply, â??rising in
> a thermal, their tales widely fannedâ??. Also, my impression from these birds
> were that they were courting, twirling around each other, which is mentioned
> for WTN in CBOAB where they will descend, twisting around each other, then
> rise, circling back up to the main flock.
> d) As the birds were twisting around each other I think I just missed the
> belly and rump, the whitish tinge on the â??chestâ?? (most similar to Slaters
> paintings of FTS) could also be the back of the WTN. I had very good
> 'focussed' views through my binos, but did have to refind the birds a couple
> of times, so probably saw the face, what I thought was the chest could have
> been the back, and then the rump/belly and tail.
> ,
> The biggest killer to my initial ID is that FTS are much more common W of the
> Great Dividing Range, while WTN are East, also the field guides mention FTS
> are gone from Australia by April, while WTN may last a bit longer. BOCG
> mentions March for WTN. Only the CBOAB mentions the end of April for FTS.
> Iâ??m very confident they were swifts, but not confident about which species.
> I would prefer them to be FTS but expect they were WTN. Itâ??s just a shame I
> didnâ??t recognise their call earlier as I wasted precious seconds looking in
> trees rather than sky. I doubt anyone could be certain on ID from my
> description, but just hope someone else saw them.
> Benj
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