FT Swift or WT Needletail??

["boy nature" <>]

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 ‘chest’ 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.
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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 I’m asking whether anyone else was outside at ~ 2:50pm Saturday. Did you see them? I’ve seen fork-tailed swifts only 2 times before and WTN about 6 times. I’ve seen plenty of swallows, martins and raptors over the past few months though.
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Here is my reasoning for what I saw/heard, above

a) I didn’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 ‘bat-like’ 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, ‘rising in a thermal, their tales widely fanned’. 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 ‘chest’ (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.
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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.

I’m very confident they were swifts, but not confident about which species. I would prefer them to be FTS but expect they were WTN. It’s just a shame I didn’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