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.