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Kia ora
This morning we did our monthly west coast Birds New Zealand beach patrol. This was at Muriwai South (near the gannet colony), as our regular site at Rimmer Road, still has no beach access. Whilst walking north, our six patrollers found 1 white-capped albatross, 1 fluttering shearwater & 2 Australasian gannets.

Whilst returning south on the wet sand, we found what looks to be a juvenile rufous fantail ? The tiny bird was found by Ariel-Micaiah Wijaya & Miguel Mejias & had been washed ashore on the receding tide that morning. I have attached four pictures for your reference.

My thoughts are that the bird is a juvenile rufous fantail. As you will see from the pictures, I have not washed or groomed the bird in any way, so the features may not be clear & I expect that the Auckland Museum will clean the the bird up to identify it properly. Some features are the rufous tail colours, brown wings, light underside & typical flycather/Rhipidura bill.

Interestingly, I cannot find any pictures or much descriptions about the ventral feathers on the tail of a rufous fantail, but the ventral tail feathers appear similar to that of a little-bronze cuckoo minutillus race !

Any comments on the pictures & identity of the bird would be much appreciated. I will be taking the bird to the Auckland Museum on Monday for identification & use as a specimen.

Kind Regards
Ian McLean

Has to be a cuckoo with the beak shape and 2-2 arrangement in toes on the feet. Oscar and others suggest little Bronze cuckoo?

I'm going for little bronze-cuckoo Ian (minutillus or barnardi), must be a young bird without any barring on the breast. An excellent addition to the Aotearoa list!

Thanks for your comments Oscar & David. Yes, I agree that it is little bronze cuckoo. Unfortunately, the rufous coloring, small size, relatively large tail & lack of any barring had me thinking rufous fantail.

I have now taken a more detailed look & some measurements. The feet are definitely that of a cuckoo, whilst the wing length of 95mm fits that of a little bronze cuckoo. The bill length is only 11mm & this & the undertail markings may fit that on the minutillus subspecies. Remarkably this subspecies is mainly found in the Northern Territory.

Attached is another picture.

Backtracking after an email from Alan Tennyson suggesting it is a Horsfield's bronze-cuckoo - this would make more sense for the lack of barring on the breast and the tail pattern also fits well, just the measurements fall a bit short as to what would be expected but this could be due to it being a juvenile/immature bird. Here are a couple eBird photos of similar birds in life:

Yes, I agree. I looked it up earlier and thought as much but wanted to check with Australian experts first so posted to the Aus bird ID FB page asking for comments on whether it was LBC or HBC. Rohan Clarke (co-author of The Australian Bird Guide) has now replied:

"It is Horsfield's Bronze Cuckoo which is by far the most likely in NZ given they occur as far south as Tasmania and are currently on the move in eastern Australia as they migrate north. The rufous in the tail is broadly OK for both species but Horsfield's shows narrow black and white bars on the underside of the outertail such that 4-5 black bars are visible whereas Little Bronze-Cuckoo has broader black and white bars in the tail so that typically only 3 black bars are visible. Even allowing for missing and disheveled undertail coverts, the barring on the underside of the outer rectrices is just too narrow for a Little Bronze Cuckoo. The extensive rufous in the other rectrices is fine with the pattern of narrow black and white bars towards the tip of each feather consistent with Horsfield's BC; here Little BC shows a single broad black subterminal band (usually with white tips) across the spread tail."

He adds: "Here is an example of a Horsfield's showing those rufous rectrices with a pair of narrow black and white bars":
https://ebird.org/checklist/S144808776? ... 62eK-mIUIM

A great find. Hopefully it'll inspire folks to do a bit more beach patrolling after strong westerly blows at this time of year. Its a species that probably turns up occasionally and simply missed. I've found them in "out-of'-range" locations in Singapore and Northern Sumatra from shrubland behind a beach to 1000m a.s.l up in the mountains. They tend to stay in 1 spot for quite a while and can be quite conspicuous as they perch in the open. Let's hope a live one is next?!

I just took some measurements before I take the cuckoo to the Auckland Museum this afternoon.

These were as follows:-
Wing length 95mm
Tail length 67mm
Tarsus 16mm
Culman (bill) 11mm

These measurements are more in line with those of a little-bronze cuckoo compared to a Horsfield's bronze cuckoo & the bill is particulary small. There can of course be individual birds that are smaller than is normal for a species.

Josie Galbraith, the curator of Land Vertebrates at the Auckland Museum will be having a look at the bird, whilst Dr Brian Gill who has studied shining bronze cuckoos will likely also examine the bird.

An update on this bird is that by Dr Brian Gill has advised that is bird is most likely a juvenile Horsfield's bronze cuckoo. DNA testing is still to take place, but it may be the first NZ record of a Horsfield's bronze cuckoo.

Just FYI: The method I used to take the initial measurements were different to that used & quoted in HANZAB e.g. I had a bill measurement of 11mm, whilst Dr Brain Gill measured 14.5mm from the base of the skull. Note that whilst the rufous dorsal plumage is very much like that of a Horsfield's bronze cuckoo, the undertail markings appear that of a little bronze cuckoo. It is a confusing bird to identify with features of both species & I am looking forward to the DNA Test results !