Friday 29 December 2017

December moths on Black Mountain


Another month, another survey of moths on Black Mountain in Canberra with Suzi Bond and Glenn Cocking. And another set of different moth species, all new to me. The one above is a species of Emerald, Chlorocoma melocrossa, Geometridae,  c 3 cm wingspan.


This one, a Triangular Geometrid Moth Epidesmia chilonaria, was not attracted to the lights but was hanging on a grass stem out in the shadows. So low to the ground that I almost stepped on it, a familiar habit of the species. The noticeably long labial palpi protrude as a pointed 'nose' between the antennae, and this one is partially showing some of her yellow hindwing. c 5 cm wingspan.

Not a moth, and not just a smudge on the bark of a tree. This is a case, a sort of tube, a onesie made of silk and pieces of fine dirt, soil, tiny specks of forest litter. And inside is a Psychidae moth caterpillar, possibly Australian Bagmoth Cebysa leucotelus, snug and safe from predators as it crawled up a branch. It feeds on lichen. c 2 cm long.


A side-on view of the same silk onesie. A tiny gap can be seen between the case and the bark. I would like to watch how these caterpillars build such hideaways around themselves as they grow and feed.


Although most of the moths were attracted to the lights and landed on the white sheet next to the lights, I like to photograph them away from the sheet, on nearby trees and shrubs. They make dramatic images, like this a Capusa sp. Geometridae, on a gum tree. c 5 cm wingspan.


This tiny moth wouldn't land on the surrounding vegetation, so I just had to accept a shot of it on the light sheet. I can't pin down this one to species, although it is likely an Oecophoridae. c 1 cm wingspan.


Isn't she so beautiful. This was probably my favourite for the night - I'll have a new favourite next month. I like her black and white socks and the fiery red/orange patch on the back of her thorax. She is a species of Cryptophasa, Xyloryctidae, c 3 cm wingspan.


I would like to find a caterpillar of one of these. They burrow into the stem of their host plant, gather food at night and bring it back to eat in their burrow during the day. But how do I find one, go out at night with a torch I suppose.


Tuesday 19 December 2017

A long sit

This pair of Tawny Frogmouths have had a bad season. Back on 6th October (seen above) they were together in their nest tree. Unusually, the female was sitting on the nest in the daytime, so I assume that was because she was laying an egg and had not finished before sunrise, so she stayed on the nest during the day. That is usually the male's task.

Sadly, they then took turns, the male sitting on the nest by day, and both for spells at night, for the next nine weeks. They must have had an infertile egg, or possibly two of them, but that would seem unlikely, and very bad luck. They only stopped trying to incubate and hatch it last week, and it is probably now too late for them to try again. When I suspected that they had a dud egg, weeks ago now, when they should have had chicks, I was tempted to climb up and take the egg away from them so that they could go ahead and re-lay. But, I don't interfere with nature, so I left them to be, sad as it is to witness.

The immediate neighbouring pair also had a dud egg, but they did have a viable one too, and they successfully hatched and fledged a chick (a few weeks ago, see above when it had just left the nest). I saw them again last week, with the chick now well developed and almost full grown since fledging on the 7th November.

The remains of their dud egg, the split shell, was lying below their nest on the day the chick fledged. It had already been eaten by an opportunist predator.

Meanwhile, the next pair along successfully raised two chicks. It is only by studying birds closely that we learn what happens to them when breeding. So many different things can go wrong in life.


Friday 1 December 2017

November Moths

Delexocha ochrocausta - wingspan c2 cm
note the long upward curved labial palps and fringed hind edges to the wings

I was out on another moth foray in the the Black Mountain woodland in November, with Glenn Cocking and Suzi Bond. Between this trip and that in October, there was quite a difference in the species and abundance of moths attracted to the lights. However, as I am simply a beginner in moth identification I was following their guidance, so what I present here is a very short list of the moths seen. All I aim to do is share my experience with others and illustrate the variety of moths, their colours and forms that can be found in one night with a light.

Wingia aurata - wingspan c2 cm
This Golden Leaf Moth has an amazing face as well as upturned hind edge to its wings. The shape and colour probably mimic a fallen leaf or piece of bark. The flash lighting exaggerates the gloss on the wing scales, it would be mat-toned in daylight when at rest.

Termessa nivosa - c2.5 cm
A Snowy Footman - what a wonderful name. This species' caterpillars feed on lichen, algae and moss and live beneath loose flakes of tree bark.

Melanodes anthracitaria - wingspan c5 cm
No common name - most moths do not have one. This is one of the abundant Geometridae species flying that night and its dark grey/black colouring fitted well on a piece of partially burned wood. There are two colour forms of this species, this and a yellow and black type. There are also two colour forms of caterpillar, green and brown. Both colours of caterpillar can come from the dark adults, but only the green from the yellow and black form. I wonder why this has evolved to the benefit of the species.

Sandava scitisignata - wingspan c2 cm
Fungi Snout - all moths should have such character names. The caterpillars of this species feed on fungi. I like mushrooms too.

Idaea costaria - wingspan c1.5 cm
A White-edged Wave - the pale leading edge to the wings, the costa, shows white in artificial light when they flutter and land around it. This is another geometridae, and like most of those species its mottled camouflage colouring blends with the substrate it lands on. In this case, a log with no bark.


Wednesday 29 November 2017

Rain and Shine


Two days ago it was torrential rain. Today it was brilliant sunshine. This male Tawny Frogmouth sat on his nest all that day covering his three chicks from the wet, with only their tails sticking out. The usual brood size for these birds is one or two, so it was bit of a squeeze under there to keep dry. Meanwhile the rain pattered off his head and back, dripped from their tails and beaded on dad's back.


Today was much brighter and dry, very dry. The youngest chick was still sticking close to its father, although he was on the nest the chicks were all out.



The oldest chick had well and truly fledged. That one was up high in the next tree hiding very well, with mum close by. This youngster was probably a week or more older than the youngest one, and this is only the second brood of three chicks fledged this year in my study area in Canberra.



These birds might seem tricky, or easy, to see when the camera has framed them, but when viewed at a wider setting, there is a more realistic impression of how well these birds can hide.



Often a view down on a nest or brood can make it a little easier to find them, but I always admire them when I do find them. They are just so good at what they do, hide and sit quietly all day, waiting for night when the woods become theirs again.

Monday 27 November 2017

Fully-fledged Frogmouths

Two well-grown frogmouth fledglings with their father on the right
On the 18th October this year I posted a feature on the first brood of Tawny Frogmouths to fledge in my study area, in Canberra. They left the nest on the 15th, and last weekend when they were six weeks old, they were fully-fledged, well almost. Compare the recent image above with that below of the same brood last month.

The youngsters now have fully-grown tail feathers, and in these pictures it can be seen how the young birds have rounded tips to these, while those of the adults are pointed. This is a common feature in birds.

Also, the young birds' under-tail coverts are still downy and white, while the adult's coverts are stiffer feathers and coloured for camouflage.

The same three birds on the 15th October - six weeks previously
Six weeks ago the young birds were only just out of the nest and still downy. Although they had well-enough developed flight feathers to flutter between trees for safety and to follow their parents around as they hunted.

The downy newly-fledged chicks 
The chicks have now lost most of their downy feathers, but a few still hung around their faces, giving the birds that still-young appearance. They could be dependent on their adults for another month yet and stay with them for longer, into the autumn or even stay with them till the next breeding season.

So at what stage can they be considered as having fledged? Well, for my study, I use the day they leave the nest as that is the only figure I can count for every breeding attempt. Many of the birds disappear into the woods after that. This is standard procedure to describe birds that have left the nest. Other birds which I study, such as Golden eagles, fledge at about twelve weeks old, but stay with their parents for another three months.

Soft downy face feathers
As is usual, it was the male who perched close to the young birds. He is larger and can give more protection against predators. The female was perched on an adjacent branch of the same tree, ready to fly in and help if any danger did approach.

The adult female