Ian’s Bird of the Week – White-browed Scrubwren ~ by Ian Montgomery

Newsletter – 5/28/15

I said in the last bird of the week that the Atherton Scrubwren was ‘probably the least distinctive of the Wet Tropics Endemics’. By that I meant it was hard to identify with certainty owing to lack of distinguishing field marks and I didn’t intend to imply that it was otherwise undistinguished. I’m actually very fond of scrubwrens. They are assertive little birds with lots of character, so here is the most widespread one, the White-browed Scrubwren by way of amends! It occurs right along the coasts of eastern, southern and western Australia from Mossman – not far north of where we were at Lake Tinaburra a few weeks ago – in far north Queensland (FNQ) to just north of Carnarvon in Western Australia. The one in the first photo was in the company of the Atherton Scrubwrens near the ‘amenities’ block in the campground.

White-browed Scrubwrens vary in plumage by location and there has been considerable disagreement among avian taxonomists over the centuries over how to divide them into species and sub-species or races. Schodde and Mason described 12 races in their authoritative Directory of Australian Birds (1999). However, the various races grade into each other and are often only distinguishable in the hand or museum. Criteria such as “feet pale flesh, drying consistently pale brownish cream, lower mandible drying variously bone to sometimes rather dusky” is not something even the most patient field worker would use.

So, it’s more usual now to lump these races into 3 mainland groups and the treat the Tasmanian ones as a separate species. We’ll take a clockwise trip from Tinaburra in FNQ to Cheynes Beach in southwest Western Australia to look at these, and then come back to the Tasmanian species. The females are paler, less-contrasty versions of the males, so we’ll just consider males, once we’ve looked at the two sexes in the distinctive Queensland race, laevigaster. The one in the first photo is a female, while the one in the second is a male. Both sexes have pale underparts that look pale yellow or buff, strong white eyebrow extending well behind the eyes and no white line just under the eye (suborbital). The male has a strikingly black mask extending over the ear-coverts, and is, in my opinion, the smartest of the White-browed Scrubwrens and looks somewhat like a pale Yellow-throated Scrubwren.

South of the Queensland border we encounter the nominate race group, frontalis. This group extends all the way through New South Wales and Victoria into eastern South Australia. The one in the third photo, taken in the Blue Mountains west of Sydney, is more rufous on the back and flanks than the Queensland race, the black on the face is limited to the lores in front of the eye (the ear coverts are grey), the eyebrow fizzles out behind the eye and the there is a faint suborbital white line.

The birding singing lustily in the fourth photo near Melbourne is also of the nominate group, though it looks darker overall and has even less of an eyebrow.

When we get to Western Australia, we encounter the ‘spotted Scrubwren’, race maculatus with dark spots on the throat and breast, buffish underparts, a long eyebrow, a clear suborbital line and, like the nominate group, the black face mask limited to in front of the eye.

The sixth photo shows the Tasmanian one It was first described as a separate species by Gould in 1838; lumped in with the other White-browed Scrubwrens in the 20th century and now restored to the grand status of a full species in the 21st century. In taxonomy, plus ça change, plus c’est la même chose, a quote from 1849, though Jean-Baptiste Alphonse Karr probably wasn’t thinking of taxonomy at the time. He did, however, have two varieties of Dahlia and a bamboo named after him. Anyway, The Tasmanian one is very dark, though in other ways such as its faint white markings on the head it looks quite like the Victorian one in the fourth photo, though the white epaulettes are very distinct. It’s also quite large by Scrubwren standards (12-14cm/4-5in in length).

Scrubwrens inhabit dense undergrowth, but as long as that is provided they occur in wide variety of habitats from rainforest to scrubby heaths and are quite common. They are both vocal and curious, responding well to ‘pishing’ noises, so they are easier to find than their choice of habitat would suggest. They’re very active, foraging near the ground, often in leaf litter for insects or other invertebrates. The breed in pairs or groups consisting of a breeding pair and helper birds, an arrangement that seems remarkably widespread across Australian bird families.

I’m off the western Queensland on Saturday. Hopefully, I’ll have some interesting dry country birds for you but don’t expect anything for another couple of weeks.

Greetings
Ian

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Ian Montgomery, Birdway Pty Ltd,
454 Forestry Road, Bluewater, Qld 4818
Tel 0411 602 737 ian@birdway.com.au
Bird Photos http://www.birdway.com.au/
Where to Find Birds in Northern Queensland: iTunes; Google Play Kobo Books
Recorder Society http://www.nqrs.org.au

Lee’s Addition:

Then God said, “Let the waters abound with an abundance of living creatures, and let birds fly above the earth across the face of the firmament of the heavens.” (Gen 1:20)

I find these Scrubwrens that Ian has been introducing very cute and interesting. Last week’s Atherton Scrubwren and now these two species are the little bird types that drive me crazy trying to photograph. Ian has a knack for getting great photos. Thanks, Ian, for sharing these with us. Happy hunting on you new quest.

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Ian’s Bird of the Week

Ian’s Whole Acanthizidae Family

Acanthizidae – Australasian Warblers

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