|
Case Summary for:
Submission No 199: House Swift Apus affinis, East Ballina, NSW, 7 March 1995. Verdict: Not Accepted This case describes a small swift flying with White-throated Needletails Hirundapus caudacutus at tree top level during strong SSE winds to 25 knots from East Ballina, NSW (28º 51’ S - 153º 34’ E) 7 March 1995. Cyclone ‘Violet’ was located 350kms East of Coffs Harbour, NSW at the time. The sighting was brief lasting approximately 30 seconds. However, the observer is 100% confident with the identification. The description provided in the submission depicts a bird shorter with a smaller wingspan than the comparable White-throated Needletail. The body length estimated to be three quarters to that of White-throated Needletail and the wing span probably half the length. The wings were held straight out and the primaries rounded. The tail was described as square ended but not noticeably long or short for the body length. More plump and stronger flying than a Tree Martin Hirundo nigricans. From the angle seen the bird appeared entirely black except for the white throat which appeared neatly demarcated from the black underparts. The white rump could not be seen due to the angle of observation. The observer also commented that the light was good enough to accurately determine colour as the greyish-brown mantle and the greenish sheen could be seen on the nearby White-throated Needletail. Members of the committee were divided in their opinion, commenting that the main shortfall was that the observer was unfortunate in that the white rump could not be seen. It is understandable that when a bird is sighted for such a short period that little information is going to be available in the way of definitive field notes, and this was felt to be the primary shortfall by the members that voted to not accept. Other members had no hesitation in accepting the record believing the record involved an honest account of a frustratingly brief sighting. The combination of (1) markedly smaller body-length and wing span; (2) square ended tail; (3) somewhat rounded primaries; (4) dark ventral plumage combined with the white throat all adding up to a positive identification. Although there are several recent claimed sightings for this species, this record represents only the second to come before the committee. The first being an accepted record from Caboolture, SE Queensland 1 January 1994 (BARC Submission No.177). This species was first recorded from Australia in 1979 (Robertson 1980). Sibley & Munroe (1990) split A. affinis into two separate species: A nipalensis in Asia and A. affinis in Africa. The Australian specimen is referable to the subspecies subfurcatus, which falls within the A. nipalensis group of Sibley & Munroe (1990). It would therefore seem likely that other Australian records would also fall into this group. Present Australian taxonomy treats the matter as unresolved and follows A. affinis (Christidis & Boles 1994). The committee resolving that this record be treated as highly probable, although not accepted.
References and Bibliography
Tony Palliser |