Talon-grappling eagles



There was a stiff breeze yesterday so I went out to watch for displaying raptors over some hills just outside Canberra - and I saw so much more than I expected. Four Wedge-tailed Eagles Aquila audax flew along the airspace at about my elevation on the hillside and two of them began to tumble down through the air, grappling their talons as they spun around and around.

These birds were all youngsters, i.e. fledged at least last year and not yet fully adult. This can be seen in the white base to their tails. Adults have dark tail coverts.

Although these birds have wing-spans of over two metres they showed that they are very agile and seemed to be in control of where they were at all times and in all directions. They would have to be or else they could have been seriously hurt.

They always grabbed the other bird's talons, never seeming to aim for anything else, or was it that each bird always fended off any strikes by the other.

They held each other by one and two talons, and I wondered if they ever drew blood from one another. Those talons are sharp and if they grasped the flesh of the other bird's foot, surely they could draw blood if they wanted to.

Then after only several seconds, the show was over. The birds let go and drifted apart. All while the third bird was watching from a few wing lengths away. And the fourth bird had drifted on along the ridge out of sight, mobbed by a trail of Australian Ravens, Australian Magpies and a Little Eagle.

Mist-netting birds

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.

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.

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.

     Top-side of Horsfield's Bronze-Cuckoo's tail     

    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.

Z.l.ochrochrous

Z.l. westernensis 

                       

Z.l.w. Rufous flanks

Z.l.o. Tawny flanks

Z.l.w. Yellow throat

Z.l.o. White throat with yellow flecks

Perhaps, the most spectacular bird we caught was a male Brown Goshawk Accipiter fasciatus in full breeding plumage. Accipiters are aggressive and can inflict cuts with their bills and talons, so great care is necessary when handling them. This powerful predatory bird was such a contrast from the docile Owlet Nightjar we began the day with.

The talons are grasped firmly and the head held up away from our hands.
The whole bird is kept well away from our faces.

The bird had clean, slate-blue upper coverts and head. Its breast and underwing coverts were solidly barred.
All its flight feathers were complete, no moult.

The rounded tail is one of the better features to look out for if in doubt whether a bird seen is a
Brown Goshawk or a Collared Sparrowhawk Accipiter cirrocephalus, which has a square-ended tail.

The bright yellow eyes of an Accipiter - a determined hunter.

Note the heavy eyebrows, these shield the eyes, not only from sunshine, but against twigs and leaves when a goshawk crashes through thick vegetation in pursuit of its prey. The brows are unfeathered and the skin shows signs of abrasion. One of the honeyeaters we caught had a 4mm long thorn stuck in the skin on its crown, an example of what birds have to contend with when flying through woodland. I pulled the thorn out cleanly and the honeyeater flew off happily.

All the birds we caught flew off back into the bush. No animals were harmed in the making of this blog. 

Butterfly list - Keswick Island July 2017

 Dark Ciliate-blue

In reply to requests from readers of the previous post, here is the list of butterflies that I saw on Keswick Island in July 2017. There were probably a few if not several more that I did not identify or never saw. It truly is a great place for butterflies.

Large Grass-yellow

Green-spotted triangle Graphium agamemnon

Clearwing Swallowtail  Cressida cressida

Narrow-brand Grass-dart  Ocybadistes flavovttatus

Orange palm-dart  Cephrenes augiades

Lemon Migrant  Catopsilia pomona

Small Grass-yellow  Eurema smilax

Large Grass-yellow  Eurema hecabe

Cabbage White  Pieris rapae

Pearl-white (Glistening?) Elodina sp

Yellow Albatross  Appias paulina

Caper Gull  Cepora perimale

Blue Tiger  Tirumala hamata

Lesser Wanderer  Danaus petilia

Monarch  Danaus plexippus

Swamp Tiger  Danaus affinis

Swamp Tiger

 
Purple Crow  Euploea tuliolus

Common Crow  Euploea corinna

Glasswing  Acraea andromacha

Meadow Argus  Junonia villida

Varied Eggfly  Hypolimnas bolina

Orange Bush-brown  Mycalesis terminus

Orange Ringlet  Hypocysta adiante

Orange-streaked Ringlet  Hypocysta irius

Oak-blue (Purple?) Arhopala sp

Dark Ciliate-blue  Anthene seltuttus

Small Dusky-blue  Candalides erinus

Purple Line-blue  Prosota duboisa

Purple Cerulean Jamides phaseli

Long-tailed Pea-blue  Lampides boeticus

Common Grass-blue  Zizina otis

Orange-streaked Ringlet

Keswick Island butterflies

I am not long back from a week on Keswick Island, one of the Cumberland group of islands in the southern part of the Whitsunday archipelago, off Mackay, Queensland, Australia. Only a week, but it has taken me about the same time to identify the butterflies I saw there. They were so easy to see that I saw most in one day, every day. I am now confident of about twenty species, thanks to help in the identification by Suzi Bond. There were about another ten species that I saw but could not grab a photograph of, and it is winter, or rather the dry season there. Here are some of my pick-of shots.



Blue Tiger Tirumala hamata, these were the most abundant species, clusters of them were roosting under branches when I first went out for a walk in the evening after unpacking the bags. I had gone out to listen and spotlight for wildlife, and this was so unexpected. Next morning there were clouds of them fluttering in the forest rides.



Varied Eggfly Hypolimas bolina - male. These butterflies were also abundant, although never in clouds. They seemed to be slow starters in the morning, much easier to photograph than the tigers. They have a lovely velvet sheen on their wings.



Clearwing Swallowtail  Cressida cressida - male, probably the second most common species. Many were freshly emerged with clean edged wings and lustrous shine. The glasswing occurs because there are no coloured scales on the translucent parts of their wings.

Clearwing Swallowtail - female. This lady still has soft wings, which are bent on the fore edges. She was fluttering low from nectar-bearing flower to the next, keen for a feed, energy and agility. Her second life had begun. What a gorgeous face.



Varied Eggfly - female. Not all the butterflies were fresh, this one was old, as can be seen by her tattered wings, very tattered wings. As this was in mid-dry season, I wonder when she emerged.



Orange Palm Dart Cephrenes augiades. Not all butterflies are large and dramatic. This species was abundant and well worth a close look. Its wingspan is only 40 mm, and see how it holds its wings, the fore-wings are half-erect. Its body was covered with hair-type cells, so it would endure the cooler nights quite easily. The temperature dropped to only a few degrees on several nights during my stay.



Purple Cerulean Jamides phaseli. We can't see it when the wings are held closed, but when this one flies it flashes a delightful purple-gloss upper-wing. Again, a lovely face, with marvelous antennae.



Orange Ringlet Hypocysta adiante. One of the trickier species to photograph. I could not capture one with its wings spread. These lived along the rough roadside vegetation, basking on the path, grasses or as here on stones. Both this and the next shot show how well they are camouflaged and disappear from our relatively poor sight when they land.



Orange Ringlet. This one was siphoning water from a mud-puddle. A favourite drinking method by butterflies. Meanwhile it is safely concealed by its resemblance to the background leaf.



Orange Bush-brown Mycalesus terminus. It is there, it is the same specimen as in the next image, so use that as a guide to its whereabouts in this picture. So many butterflies are difficult to see when they land. We tend to have to flush them first by accident, then watch until they land again. I memorise the exact surroundings, mark the spot and creep up slowly for a close view.



Orange Bush-brown. Now, can you see it. The shadow of the grass across the wing hides it from this angle, matching the dark fore-edge to the wings.



Monarch Danaus plexippus. It goes dark early in the tropics and by late afternoon most of the butterflies were slowing down and settling to roost as it grew dark. Each species have there own roosting sites, and this Monarch was amongst the Blue Tigers, back in the first roost I discovered. Thirty species in one day, perhaps more. Not a bad winter count. What is it like in summer.

Simon's crowdfund appeal















































Today I went into the Pozible website to add a pledge to Simon Cherriman's crowdfunding appeal. Then I noticed he has used one of my images of him climbing up to an eagle eyrie in Western Australia. That was taken last year and it was a great day out with a great guy. Simon is such an enthusiastic worker, and he works hard at a hard task. He deserves all the help we can give him. His appeal is for five satellite tags which he hopes to attach to wedge-tailed eagles, then follow their movements across Australia. This is all part of his PhD project. Do have a look at his appeal by following the following link:

https://pozible.com/project/wheres-wailitj

Than have a look at his websites too, to see what results can be gained from his eagle studies:

http://wedge-tailedeagletracking.blogspot.com.au/ 

and what other conservation work he does:

http://simoncherriman.com/Simon_Cherriman/Home.html