At 10:25 20/11/98 +1100, Tony PALLISER forwarded:
>
>this is a general release from Project Diadema 98, concerning
>the recent rediscovery of the NC Owlet- Nightjar. No calls were made and
the bird
>was not relocated This is the
>first sighting of the New Caledonian Owlet-Nightjar since 1880
>Subsequent searches at this site in the following week for five days and
>nights provided no further records of this bird, either aural or visual,
>despite the use of playback and intense fieldwork...
A fascinating discovery. The NC Owlet-nightjar (Agotheles savesi) was known
only from a unique skin (the type specimen) and some subfossil bone
remains. It has long been been presumed extinct. It has usually been
treated as a subspecies of the Australian Owlet-nightjar (A. cristatus)
(Delacour 1966; Hannecart & Letocart 1983), or as a sister species to A.
cristatus (Mayr 1945; Schodde & Mason; Peters World Checklist). However it
has been clearly shown to be a distinct species not at all closely related
to A. cristatus (Olson et. al. (1987). These authors compared skins and
skeletons of all extant nightjars with the material of A. savesi.
What puzzles me is if the recently discovered bird was not heard then the
call of this species remains unreported. Yet the project Diadema '98 team
used playback techniques?! Presumably they used calls of A. cristatus??
There is also a lost (presumed extinct) "eared" night-jar from New
Caledonia. The New Caledonia Nightjar (Eurostopodus [mystacalis] exul) is
also known only from a single skin, the type specimen. This was a female in
"egg-laying condition" (Mayr, 1941). Its call is also unknown. Mayr (1941)
described the differences from White-throated Nightjar (E. mystacalis) of
Australia as : (1) much lighter upperparts; (2) almost solid black crown;
(3) little rufous in collar; (4) bolder, unbroken wing-bar on p9-p7; (5)
inner webs of primaries, solid black or with faint rufous bars but no buff
spots; and (6) smaller size (wing 184, tail 138, weight 77). It was treated
as a subspecies of E. mystacalis by Mayr (1941) because it is closest to E.
mystacalis in appaerance and because the "equally distinct" E. nigripennis
(little known of the Solomon Is.) was usually considered a subspecies of E.
mystacalis in those days. Subsequent authors (May 1945; Delacour 1966;
Hannecart & Letocart 1983) have mostly considered exul a subspecies of
mysticalis, except Balouet & Olson (1989) treated it as a full species in
its own right, without explanation. It could be anything form a totally
unique species to a winter refugee from eastern Australia!
Is there a chance that this rediscovery could refer to the nightjar rather
than the owlet-nightjar? Obviously the wingbars would be a give-away, but
perhaps the bird was watched in the gloom of dusk without a spotlight? The
constant hawking behaviour is curious. In my experience Australain
Owlet-nightjar does not "hawk" as such but forages on the wing in short
direct sallies from perches or pounces on prey on the ground. Perhaps the
insular A savesi differs ecologically from a. cristatus in this regard?
I hope that a full write-up of this great discovery will appear in time.
REFERENCES
Balouet, J.C. & S.L. Olson. 1989. Smithsonian Contributions to Zoology 469.
Delacour, J. 1966. Guide de Oiseau de la Nouvelle-Caledonie et des
Dependances. Editions Delachaux et Niestle, Neuchatel.
Hannecart, F. & Y. Letocart. 1983. Oiseaux de Nouvelle Caledonie et des
Loyautes. New Caledonian Birds. 2. Les Editions Cardinalis, Noumea, New
Caledonia.
Mayr, E. 1941. Am. Mus. Nov. 1152.
Mayr, E. 1945. Birds of the Southwest Pacific. Macmillan, New York.
Mayr, E. 1945. Birds of the Southwest Pacific. Macmillan, New York.
Olson, S.L. et. al. 1987. Gerfaut 77: 341-352.
Schodde, R. & Mason, I.J. 1982. Nocturnal Birds of Australia. Landsdowne
Press.
David James
PO BOX 5225
Townsville Mail Centre 4810
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