Great-tailed or Boat-tailed Grackle? Nolton Haven, Pembrokeshire, Wales. (1 Viewer)

[phil baber]

As a lot of birders in the UK are aware, there is a Grackle species at Nolton Haven, in Pembrokeshire, West Wales. It was discovered last week. And could represent a first record for the British List. (Whether ship-assisted or not, it is a very important record!)
From its initial discovery to now it has been identified as a female Great-tailed Grackle (Quiscalus mexicanus.)
We only live 18 miles away, so yesterday took the opportunity to go see it. Never having seen a live Grackle before, I took lots of footage in various, often poor lighting conditions between rain showers.
Doubts were being raised yesterday as to whether the initial ID was correct, and that (Atlantic) Boat-tailed Grackle (Quiscalus major) might be a better fit for ID?
And I believe this debate is continuing.
So today I took as many useful grabs as I could from my footage, to assist in showing people how the bird looks under various light conditions, and with as much structural and plumage detail as possible.
Putting these images here will give a better platform for debate and discussion. And, I hope, some valuable input from the wonderful American birding collective. (Who are the people who should know!)
Sibley can only take you so far after all...

Thanks in anticipation of any constructive feedback here.

 

[phil baber]

More images...

 

[Ruff-Leg]

I live in Great-tailed country, and my experience with Boat-tailed is a couple of years old, so I'm going on out on a limb here. I'm leaning towards the former. Supercilium, malar region, very pale eye, and head shape point me towards Great-tailed. Yes, Sibley can only take you so far, but referring to Jaramillo and Burke's New World Icterids (Helm/Princeton 1999) is supportive of GT.

I welcome being corrected.

 

[Mono]

Have you seen this thread.... https://www.birdforum.net/threads/great-tailed-grackle-pembrokeshire.447067/

 

[phil baber]

Have you seen this thread.... https://www.birdforum.net/threads/great-tailed-grackle-pembrokeshire.447067/

Yep. Of course.
Just providing lots of images for people to understand how to 🆔 these 2 species.
From the outset there has been no instructive information as to how this bird has been identified as a GtG? Without saying why it's not a BtG?
This thread is not designed to claim that it's either species.
Just to facilitate better communication about 🆔 for a difficult species new to UK.
Already Ruff-leg has offered some positive response from US.
Let's keep it coming.
Poop was collected yesterday to be sent for genetic analysis.
The true ID lies there.
I have no opinion either way. But seek to learn. And if anyone can learn also from this, about a bird not seen here before?
Then that's a very good thing.
👍
Blind acceptance of an 🆔 by someone, needs backing up by a response to why that 🆔 was made. It seems that's not been forthcoming?
I'm happy either way. Great or Boat.
But I'd like to learn why?
Maybe we just have to wait for the DNA poop results?
Enjoy the grabs anyway! Grackle on! 👍

 

[phil baber]

I live in Great-tailed country, and my experience with Boat-tailed is a couple of years old, so I'm going on out on a limb here. I'm leaning towards the former. Supercilium, malar region, very pale eye, and head shape point me towards Great-tailed. Yes, Sibley can only take you so far, but referring to Jaramillo and Burke's New World Icterids (Helm/Princeton 1999) is supportive of GT.

I welcome being corrected.

Thanks for that Ruff-Leg! 👍🏼

 

[01101001]

Have you seen this thread.... https://www.birdforum.net/threads/great-tailed-grackle-pembrokeshire.447067/

It is there that the possibility of it being a Boat-tailed Grackle was first tentatively raised on the 2nd page; much later downthread some people (including me) further tried to make sense out of it.

 

[rkj]

Have you seen this thread.... https://www.birdforum.net/threads/great-tailed-grackle-pembrokeshire.447067/

I did not read the whole thread (what I did read had little to do with identifying the bird) so perhaps this has already been addressed, but I did not see any comments about vocalizations. Have any been recorded? If not, it might be worthwhile to see if it reacts to recordings of the two species.

 

[Jos Stratford]

The two grackle threads are basically duplicating and I would say more useful if merged. Any detractors?

 

[01101001]

That many American members don't visit British rare birds news and it is them we want to reach out to, is the raison d'etre of this thread, in my opinion.

EDIT: Also

I did not read the whole thread (what I did read had little to do with identifying the bird)

(The first circa 10 pages have little to do with it.)

There was just one mention of vocalisations, i.e.

A poo sample was collected today by someone and I was also told the call is consistent wit Great tailed

I did suggest playback, but--so far--I have no information about whether anyone tried it and what the results were. I should suppose (wrongly, perhaps) that the greatest difference is in the song (mostly (?) performed by the male, i.e. what the female bird would hear and its reaction) as opposed to the calls given by the female herself (if it's a female indeed).

 

[nartreb]

This is a difficult pair to separate, US birders generally rely on location. In the area where they overlap, they differ in eye color, but that doesn't help us in the case of vagrants (ship-borne or otherwise), since both species can have yellow eyes as seen here.

Another field mark is that boat-tailed generally shows a more rounded head-shape, though this is not easy to judge as it depends on whether the bird is lifting its forehead feathers (you can see examples above where the mystery bird has them in either position).

Finally, boat-tailed females are described as having a more "subtle face pattern" compared to great-tailed, but this is very difficult to judge and again depends on feather position and condition as well as lighting and camera.

My nonexpert guess is that this one is a great-tailed, but if I read the other thread correctly, someone has promised to get a DNA sample from guano, so we shall be better informed soon.

 

[foresttwitcher]

Seems as though a call recorded has provided the ID: https://www.birdforum.net/threads/great-tailed-grackle-pembrokeshire.447067/page-14#post-4544556

 

[Andy Adcock]

The two grackle threads are basically duplicating and I would say more useful if merged. Any detractors?

I detract Sir
I think it's best to keep them separate, as stated in post 10 here, not many Americans will looks at the UK rare bird page so valuable insight may be lost.

 

[Jos Stratford]

Fair enough 👍

 

[wolfbirder]

Like many I am a total novice and my view certainly should not carry much weight.

The one feature I had an issue with was the raised head shape but in Phil’s photographs it sometimes looks flatter.

I think the call captured does indeed support Great-tailed.

I love threads like these as it’s almost a ‘live learning curb’ as Phil emphasises. But concurrently I guess posts like mine, on that thread, may appear annoying to some. I don’t intend to annoy others, and I think most posters know anyway, which birders views likely present most accuracy.

 

[rkj]

For me the face pattern and calls are a bit better for Great-tailed Grackle, but as others have said it may be that only a DNA test would be conclusive.

 

[Brett Richards]

For me the face pattern and calls are a bit better for Great-tailed Grackle, but as others have said it may be that only a DNA test would be conclusive.

I asked on the other thread if females can show the blue tint to the mantle etc, but no-one has really answered this.
Brett

 

[Farnboro John]

I asked on the other thread if females can show the blue tint to the mantle etc, but no-one has really answered this.
Brett

The National Audubon Guide on the net has a photo gallery that shows multiple pictures of adult females showing the iridescent colours on the mantle. Assuming their identifications are right, no problem...

Great-tailed Grackle

Wherever it occurs, this big blackbird is impossible to overlook -- especially the male, with his great oversized tail and incredible variety of callnotes. In the southwest, flocks of Great-tailed...

www.audubon.org

Cheers

John

 

[Andy Adcock]

I asked on the other thread if females can show the blue tint to the mantle etc, but no-one has really answered this.
Brett

It seems to be illustrated in Sibley Brett.

Sibley also shows warmer underparts on Boat-tailed as I've already written and a reduced contrast between wings and back on Great-tailed, both features would seem apparent here so not really helpfull?

 

[Brett Richards]

It seems to be illustrated in Sibley Brett.

Can't really see it myself, and the females in the Audubon guide gallery don't really show a blue tint to the mantle that I can see, not like the Nolton Haven bird anyway. Images in the Cornell Lab website show a blue tint to the scapulars and coverts, but I haven't seen an image of a female where the mantle is the bluest part of the plumage.
Brett