Wednesday, 6 September 2017

Bird ID Correction from 01 March 2017

Brown Goshawk v Collared Sparrowhawk

At our visit to Macalister Wetlands back in March, we [probably, me/I] called an overflying raptor a female, juvenile Brown Goshawk. See the blog here. Whilst "cleaning up" my bird images on the computer today, I looked again and decided I may not have been correct. I put the image onto the FaceBook Australian Bird Identification page and Luke Flesher and Angus Daly confirmed my thoughts.

Critical aspects of this bird are:

There is no evidence of moulting [shorter feathers growing out] interfering with the features of identification.

Tail feathers
The difference between the two species is in the length and shape. CS have shorter inner retrices so the tail should appear "squared off" and generally have a central notch. This is the case here. The tail is not rounded and you can just see a small notch. BG have outer retrices which are progressively shorter giving BG tail a rounded appearance.

Tail Length cf Leg Length
The BG has a long tail and, when viewed from below, there is a lot of tail uncovered by legs. The CS has a relatively shorter tail and, as above, the legs take up a bigger proportion of the tail length.

Toe length
The middle toe of the CS is much longer than the BG relative to the other toes on the foot. The legs are also quite slender compared to BG. BG legs look like they couldn't break but CS legs look like a decent bang would break them!

These wings are quite wide. The Australian Bird Guide for CS says, "Secondaries bulge beyond the rest of the trailing edge of the wing". This is what we see here.

The smallest bird is a male CS [30cm]. Next biggest is a female CS[40cm]. Only slightly bigger is a male BG [40cm] and the biggest is a female BG [50cm].

Both Morcombe and Pizzey quote the same figures. When a single bird flies over with no reference to anything else [where was the harassing magpie you may well ask?], it is very hard to judge size. On the day I recall John and I both thought it was a "large" bird, larger than a CS would be. But I was wrong. Just goes to show how challenging our hobby can be.

Juvenile, probably male, Collared Sparrowhawk.

170906_Peach Flat

Although the quantity of species was not extravagant [46], the 10 birders plus Rod and Michele saw a quality gathering. A slow walk around the lakes, with water about 2 feet below full, took until morning tea. Flame Robins,  20+ Satin Bowerbirds, a Hardhead, Aussie and Hoary-Headed Grebes, resident White-faced Herons, two Little Pied Cormorants, Flame Robins, overflying Yellow-tailed Black-cockatoos, Willie Wagtails, plenty of European Coots with one youngster and Flame Robins [8] were the standout species. Did I mention Flame Robins? There were 3 fully coloured males and 5 females/juveniles. The Australian Bird Guide tells me they are "often seen in loose groups of up to 20 birds ... the only Petroica to form flocks". They had accompanying escorts of Yellow-rumped Thornbills. Just magic. Good images taken by all in nice dry weather but a bit windy.

Light drizzle accompanied morning tea after which we walked up George Creek for 650 metres then ascended to a ridge top with nice views then returned to our morning tea stop for lunch. The only new birds we saw during our walk through the dry forest with manuka and dogwood understory were Yellow-tufted and White-naped Honeyeaters. Nice dry weather for walking.

Back for lunch and the variable weather swung between some light rain again and brilliant sunshine during which Bev saw a Mistletoebird, Heather saw 20+ Satin Bowerbirds again. We had finished lunch and were starting to pack up to go when the superstar arrived.

A male Rose Robin. Excellent views by all. LOTS of images taken. A most amenable bird. For the day we saw Flame, Scarlet and Rose Robins and Jacky Winter. Four of the potential eight robins at Peach Flat. A great day and a big thank you to Rod and Michele for hosting us.

Images: Alexander, Winterbottom

Australasian Grebe Tachybaptus novaehollandiae

Hoary-headed Grebe Poliocephalus poliocephalus

Hardhead Althea australis male

Satin Bowerbird Ptilonorynchus violaceus

Yellow-tufted Honeyeater Lichenostomus melanops melanops

Flame Robin Petroica phoenicea First two images, male. Third image, female

Scarlet Robin Petroica boodang, male

Jacky Winter Microeca fascinans

Rose Robin Petroica rosea