White winged Black Tern -Nelson Boulder bank

[BerndHuss]

Lately they were consistently right by the car park next to the water treatment plant. You should see them as soon as you get out of the car. At high tide they sit on the top of the bank and it can be difficult to approach without disturbing them. At lower tide it's easy to observe them from the top. Good luck

[Wrybill]

Thanks!!!

[BerndHuss]

Two White-winged Black Terns present today.

[BerndHuss]

A photo featuring both WWBTs

[Wrybill]

Wow, hopefully I can pop in later today or tomorrow!

[BerndHuss]

I visited Saturday and Sunday and both WWBT's were there. Quite easy to see well. You should be lucky!

[andrewcrossland]

reckon these may have both been born in NZ...... you rarely see them this dark at this time of year.............. hmmm

[BerndHuss]

I am not an expert on Terns by any means, but have there been any records of WWBTs breeding in New Zealand?

[Oscar Thomas]

Yes, details here: https://nzbirdsonline.org.nz/species/white-winged-black-tern

It's pretty bizarre that some have flipped hemispheres and plumage cycles!

[Ian Southey]

Sorry Andrew - The wings are evenly dark because they are heavily worn juvenile feathers, all the same age and not yet moulted since they first grew. The grey backs are fresher feathers from a more recent partial moult - a fairly normal immature non-breeding plumage. We used to call this first winter plumage - but its summer so these birds have come from the north. I suspect wing moult will begin soon.

Bernd - The first record of White-winged Black Terns in NZ was a pair in breeding plumage on Waihopai River in December 1868 so its not a new thing. Birds with reversed moult like this are seen pretty much every year and you may have noticed quite a few records on this forum. There can't be many of them though. They seem to be erratic in their occurrence and can appear anywhere in the eastern South Island. In spite of this there are at least four firm breeding records (https://nzbirdsonline.org.nz/species/wh ... black-tern) but they are pretty elusive and enigmatic. I don't think that we even know whether they are the same as the northern hemisphere birds or a distinct subspecies. They've intrigued me for years but I've never managed to catch up with one.

Ian