Pied Currawong Identification Challenge

ID CHALLENGE Friday 9 October 2020: Advanced by Janine Duffy

You all know this bird, to genus level anyway. But getting to species level is the tricky bit with this one. Especially when I tell you that it was seen at the You Yangs, just west of Melbourne VIC.

Solution:

Pied Currawong Strepera graculina ssp ashbyi

But it’s grey! No white wing bar! No white rump! Yes, I tell you this one caused me trouble too. I was unaccustomed to seeing Pied Currawongs in the You Yangs until a few years ago – all the ones I knew were from East Gippsland, subspecies nebulosa and easy to pick from the white rump and wing bar.

But just west of Melbourne, from about Geelong through the Otways and Surf Coast there is this cheeky subspecies ashbyi that looks for all the world like a Grey. The only major difference is the bill shape and the call.

The bill on a Pied is always very deep, with a strongly rounded upper mandible as this bird shows. The bill on a Grey Currawong is more triangular, pointed and sharp-looking.

Subspecies ashbyi have a reduced white rump, reduced white wing patch and dark grey plumage compared to other subspecies of Pied Currawong. I believe this bird is an ashbyi Pied Currawong.

As to the bird’s age, well… There is no sign of a pale gape on this bird, a feature that is supposed to persist until 6months of age or longer. The tail tips are rounded, where immatures should have pointed tail tips. There is, though, a hint of buff colouring on the coverts (not much, but it’s there and its not a trick of the light). So I am inclined to conclude that this bird is immature very close to adult.

How and when they got there, that’s interesting. I remember seeing my first Pied Currawong in the You Yangs in 2010. Before that, they were rare there. The document that Sonja shared (below), written in 2017, shows the northerly limit of the range of ssp ashbyi at Geelong, ssp nebulosa in the Brisbane Ranges and no currawongs in the You Yangs. But it does cite Trevor Pescott (1983) that ashbyi-type currawongs dispersed to the You Yangs in winter.

They are now seen regularly in the You Yangs, with records in all months.

I don’t recall if my first sighting of Pied Currawong in the You Yangs was a nebulosa or ashbyi, but I id-ed it on the call, so I know it wasn’t a Grey.

So has ssp ashbyi extended to become resident in the You Yangs? Or have a bunch of nebulosa from the Brisbane Ranges or Melbourne and some ashbyi come to the You Yangs and bred, and this was just one ashbyi-looking hybrid? I don’t know.

I’ve learnt something from this – take photos of every currawong I see over there!

https://www.birdlife.org.au/afo/index.php/afo/article/view/2073?fbclid=IwAR2JloucJzY2kY8h64sgYqFoxrf4twMNDzUGTQU9IF9eVVw9TJUxVnUBmrc

Learn more: https://www.birdlife.org.au/bird-profile/pied-currawong

See more pics: https://ebird.org/species/piecur1

Comments:

Sonja Ross: Interesting! There is/was (apparently status debated according to the ABG) a sub-species in western Vic., which fits with the location to an extent, ashbyi, which has slaty-grey plumage and very restricted white in the base of the primaries and tail. Apparently because of environmental changes there has been hybridisation so may be extinct. However, I just checked on the net and there is an article in Australian Field Ornithology, and I’ve just copied part of the abstract:

“The most southerly of the six described subspecies of the Pied Currawong, Strepera graculina ashbyi, is perhaps the least known and most controversial. Because it has reduced areas of white at the bases of the primaries and at the bases of the rectrices, its appearance is superficially similar to the Grey Currawong S. versicolor, and this has caused confusion from the time of its first description to the present day. Subspecies ashbyi is considered to be extinct by some authorities, yet our observations indicate that birds showing the phenotypic characteristics of ashbyi are common breeding residents in the Otway Ranges of southern Victoria and in the regional city of Geelong and surrounding area.” https://www.birdlife.org.au/…/ind…/afo/article/view/2073. It’s from 2017 I think.