This is the adult male's plumage - the female is plain grey.

The bird in the photo was engaged in territorial activity at Anakie Gorge, where two males were vying for the attention of a female a month ago. Photographer Carol Hall describes them fluffing out their feathers, pointing their heads to the sky, and emphasising their yellow collars as they danced around the branches for 10-15 minutes. The female watched, quietly chirping from time to time. The males appeared quite rotund as they displayed, and the enlarged collar around the back of their neck was prominent.

This yellow collar is often completely hidden, but this recent report reveals that it is important in display. Autumn seems an odd time for such a display, but perhaps one of the birds was an intruding male in the territory of an established pair.

A male golden whistler is indeed a handsome bird, its bright yellow breast accentuated by binoculars or telephoto lenses. The same can be said for the yellow robin, which can appear soft yellow with the naked eye, but much brighter through binoculars.

Although the rufous whistler is rather similar in plumage pattern (but not colour) to the golden whistler, it lacks a similar collar. The rufous whistler is a migrant, but the golden whistler remains with us all year, often moving into open forest and gardens during winter. The grey females and immature birds are more numerous than fully-coloured males. In summer, they mostly go to thicker vegetation along forest gullies.

The golden whistler is larger than a sparrow, but smaller than a blackbird. Like other whistler species, it lives up to the second part of its name by having some attractive clear whistling notes, frequently heard in spring and summer.

TRIP TO NEWSTEAD

Ten species in the honeyeater family were found on a recent bird outing to Newstead. Black-chinned honeyeater, yellow-tufted honeyeater and fuscous honeyeater were included.

Other interesting birds were tawny frogmouth, hooded robin, rose robin, diamond firetail and yellow thornbill.

The Newstead area provides opportunities to see several birds that are now scarce closer to Ballarat, including three of the above.

The hooded robin has almost gone within 40 kilometres of Ballarat, while the diamond firetail is scarce. The yellow thornbill is uncommon, but is still found irregularly at a few places.

Is this some sort of chrysalis? B.W., Talbot.

This is the egg case of one of the native mantises (mantids). It was probably produced by a large, light-brown mantis - a stick mantis, or light brown mantis - quite a common insect, but seldom noticed because of its camouflage. It is longer and thinner than the common green praying mantis found in gardens

The egg-cases of these brown mantises are 20mm or more high.

There are numerous eggs inside these cases, each in its own separate chamber, and with its own exit.

The size of the egg case is surprising, given the size of the insect. The common green praying mantis produces a smaller, firmer, more linear egg case, quite different from this large ovoid "dry foam" one.

Mantises are more common than we think - they are so well-camouflaged that they are rarely seen.

Questions and photos are welcome. Email to rthomas@vic.australis.com.au, or send to Roger Thomas at The Courier, PO Box 21, Ballarat, 3353.