Mist-netting birds
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Owlet Nightjar Aegotheles cristatus |
I was out mist-netting birds last weekend at The Charcoal Tank Nature Reserve, New South Wales, on a trip organised by Mark Clayton. The aim is to catch a sample of birds several times a year as part of a long-term study of the changes in the numbers and species in the bird population. The nets were set the evening before and opened at first light, hence we caught this nocturnal bird, an Owlet Nightjar. This is the first I have seen caught in almost-daylight. Perhaps it had been feeding late because it was a cold night at the end of winter and there were few insects about.
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Small, quiet, with big dark brown eyes, a long tail, and dark grey plumage
- all ideal for a nocturnal woodland bird |
Owlet Nightjars are neither owls nor nightjars, they are classed in a family of their own, Aegothelidae. They roost by day in tree hollows and hunt at night, feeding on invertebrates, mostly insects, which they can catch in flight although they spend much time foraging on the ground. They are small dainty birds, only about 50g in weight, and they have a soft plumage similar to owls and frogmouths, for quiet flight.
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Horsfield's Bronze-Cuckoo Chalcites basalis - the broad dark stripe over its ear coverts and the scalloped,
buff tips to the wing coverts are diagnostic markings of the species. |
As the day opened up we heard four species of cuckoo calling: Pallid
Cacomantis pallidus, Fan-tailed
C. flabelliformis, Shining Bronze-Cuckoo
Chalcites lucidus and this one, Horsfield's Bronze-cuckoo. We caught four of this last species and all were males, indicative of how male cuckoos, and many other species of birds, tend to migrate to their breeding grounds ahead of the females. The tail patterns, both topside and underneath, are diagnostic of the species' sex - the females have russet colouring on the outer tail feathers, the males, like this one, have black and white outer feathers.
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Top-side of Horsfield's Bronze-Cuckoo's tail |
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Underside of tail |
We caught a good number of regular breeding birds of the area especially White-plumed Honeyeater
Ptilotula penicillata and White-eared Honeyeaters
Nesoptilotis leucotis for comparisons of biometrics. Our sample included a good mix of species; some resident, some returning to breed and some migrants passing through. There were examples of two races of Silvereye,
Zosterops lateralis; the local
Z.l. westernensis and the migrant
Z.l. ochrochorous which breeds on King Island in the Bass Strait. We also caught fifteen Striated Pardalotes
Pardalotus striatus at once in one net and there were three races in that flock;
P.s. striatus which breeds in Tasmania,
P.s. substriatus which breeds in the interior of the continent and
P.s. ornatus which breeds in the south-east.
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Z.l.ochrochrous |
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