Ian’s Bird of the Week – South Island Wren/New Zealand Rockwren

New Zealand Rockwren (Xenicus gilviventris) by Ian 1

New Zealand Rockwren (Xenicus gilviventris) by Ian 1


Ian’s Bird of the Week – South Island Wren/New Zealand Rockwren ~ by Ian Montgomery

Newsletter – 1-9-12

Happy New Year! To celebrate the New Year, here is a representative of an unusual new family for the website, the New Zealand Wrens. There it is usually called the Rock Wren, though its international name is the South Island Wren, to avoid confusion with the unrelated Rock Wren of North America.

I used the Birds of New Zealand Locality Guide by Stuart Chambers to plan my trip and, in it I read: ‘The Rock Wren(Rockwren) is one of New Zealand’s rarer species and one of its more difficult birds to find. It is also one of its gems.’ This of course proved compelling and, as one of its prime sites was near the Homer Tunnel on the way to Milford Sound where I was after the Fiordland Penguin, I made an effort to find it. Compared with say the notorious Australian Grasswrens, this proved relatively easy as the birds often stand on prominent rocks in fine weather, where they bob up and down in a very endearing way, and I found a pair on the second attempt.
New Zealand Rockwren (Xenicus gilviventris) by Ian 2

New Zealand Rockwren (Xenicus gilviventris) by Ian 2

Their upright stance and short tails gives them, like Pittas and Penguins, the fascinating appearance of little people and these are tiny. They measure 10cm/4in in length and the males, weighting about 16g are smaller and lighter than the females at 20g. They’re tough little birds, though, and occur only in rocky Alpine habitats above the tree-line on the South Island. the third photo shows where I found them.
New Zealand Rockwren (Xenicus gilviventris) Habitat by Ian 3

New Zealand Rockwren (Xenicus gilviventris) Habitat by Ian 3

They have a flexible diet with a preference for invertebrates but also eat grass seeds and fruit. The bird in the fourth photo, has just caught a substantial grasshopper, presumably, given the season, for nestlings. The sexes differ in plumage and the green bird in the first two photos is a male. The one with the grasshopper looks browner, but I’m unsure whether that’s because it’s a female or is due to the angle of the light.
New Zealand Rockwren (Xenicus gilviventris) by Ian 4

New Zealand Rockwren (Xenicus gilviventris) by Ian 4

Only two species of New Zealand Wrens – the Acanthisittidae – survive, the other being the even smaller but more widespread Rifleman http://www.birdway.com.au/acanthisittidae/rifleman/index.htm , so named because of its upward tilted bill. This family has no close relatives among the Passerines and has long baffled taxonomists as reflected in the choice of Xenicus for the Rock Wren, meaning ‘strange’ (from the same Greek word as xenophobia). Recent DNA studies suggest that they diverged from the other passerines early in their evolution and probably qualify for their own sub-order, separate from the ‘true’ song birds the Oscines, and the mainly South American Sub-Oscines (which include some Australian representatives, notably the Lyrebirds and the Pittas).
I’ve added to the website most of the new Australian species from the Sub-Antarctic and Tasmanian sections of the trip – http://www.birdway.com.au/index.htm#updates – and am now working on the New Zealand additions. To accommodate them, I’m expanding the Australian section of the website to Australasian and indicating on the Australasian thumbnails whether each species is on the Australian and/or New Zealand lists. For an example, have a look at the Stilts and Avocets: http://www.birdway.com.au/recurvirostridae/index_aus.htm . As part of this change, I’m switching the taxonomic sequence of the Australasian section from Christidis and Boles, 2008, to Birdlife International. This will simplify the overall structure and cater for New Zealand additions not covered by C & B.
Best wishes

Ian

Ian Montgomery, Birdway Pty Ltd,
454 Forestry Road, Bluewater, Qld 4818
Phone: 0411 602 737 +61-411 602 737
Preferred Email: ian@birdway.com.au
Website: http://birdway.com.au


Lee’s Addition:

Four inches is a very tiny bird. Looking at photo #3, I am amazed that they found that little bird. Way to go, Ian.

let the inhabitants of the rock sing, let them shout from the top of the mountains. (Isaiah 42:11b KJV)

The Rockwren is in the Acanthisittidae – New Zealand Wrens Family. They are Passeriformes Order birds. Ian uses the Birdlife International for his list, whereas this site uses the IOC list. Very little differences.

See – Ian’s Birds of the Week

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