Chatham Island Prions

General birdwatching discussion, help with bird identification, and all other things relating to wild birds and birding in NZ that don't fit in one of the other forums.
User avatar
Steve Wood
Posts: 382
Joined: Sat Dec 05, 2009 6:57 pm

Chatham Island Prions

Postby Steve Wood » Fri Feb 23, 2024 8:56 pm

After close examination of all my images of Prions photographed around the offshore Islands,there appears to be three distinct Prion species but only two of them I’m pretty confident of there id.The most photographed and “mystery Prion” for me, and most abundant, although none in any large numbers is Prion B).which as you can see is somewhere between Fairy Prion A) and Fulmar Prion C) or better known now as Pyramid Prion.
Difference being on bill structure, very dark tail tip, distinct pale throat and neck, highlighted by dark cap and lores.Another prominent feature of these “Type”was the dark flecking on the mantle and sometimes on the rump.
See below.

I did hear some thoughts that the Prion’s on the Forty Fours are different again ?? which would make sense and potentially explain these birds.

Your thoughts anyone,
IMG_1274.jpeg
IMG_1274.jpeg (183.14 KiB) Viewed 776 times
Ian Southey
Posts: 1100
Joined: Tue Sep 08, 2009 5:45 pm

Re: Chatham Island Prions

Postby Ian Southey » Sat Feb 24, 2024 11:52 am

Steve

The first point is that bird B appears to have had a tough season and looks to have very worn plumage but not to have begun moult yet - you can see the soiled whites, and a patchy crown and mantle. It will look better in a couple of months.

The next point is that it has a distinct bill shape. Adults are a bit more robust than juveniles I believe but this may be more different than that.

The last point, which you seem to be hinting at, is that in a taxonomic sense Fairy Prions are almost certainly a group with more to give. If beach patrolling and you get a decent haul of Fairy Prions there are sometimes clear groups of larger and smaller billed birds. The most recent taxonomic study (https://journals.plos.org/plosone/artic ... ne.0275102) that splits off the Fulmar Prion also shows that the whole group is much more interesting than this. The Pyramid Prion was the low hanging fruit, in sympatry with Fairy Prions and supposedly not interbreeding, morphologically distinctive, not the closest relation of the other Fulmar Prions and already named.

Less clear but still interesting is that the Subantactic Fairy Prions (eatoni) are, for one gene, as genetically distinct from other Fairy Prions as Fulmar and Pyramid Prions and form a discrete group.

The remaining Fairy Prions are geographically structured although not strongly different from each other or clearly defined yet. There seems, more or less, to be a Snares Island group that has a most common ancestor with Fulmar Prions, a Chatham Island group that has a most common ancestor with Pyramid Prions, a consistent, although not strongly defined group of birds from the Poor Knights and Cook Strait and I'm not sure what to make of the Foveaux Strait and Otago birds.

Differences between the Fairy Prions are small and not necessary clear or consistent but there is one good clue that more than one species may be involved. The most common ancestors of Fulmar and Pyramid Prions come from different groups within the Fairy Prions. This makes Fairy Prions paraphyletic. I don't think that there is enough information now to go further than the authors of this paper have but one day there may be.

Prion taxonomy is heavily focussed on bill shape for obvious reasons but possibly a close look at pictures from the differnt populations might show unrecognised plumage differences. Face patterns and the amount of blue on the body might be two things worth looking at.
User avatar
Michael Szabo
Posts: 2533
Joined: Sun May 08, 2011 12:30 pm
Contact:

Re: Chatham Island Prions

Postby Michael Szabo » Sat Feb 24, 2024 4:02 pm

Dave Boyle recently posted these photos via Facebook of Forty Fours Fulmar Prions at the nest which look like the 'B' type prions we saw on our recent Chathams pelagic trips.
Fulmar Prion Forty Fours Dave Boyle 1.jpg
Forty Fours Fulmar Prion, Dave Boyle
Fulmar Prion Forty Fours Dave Boyle 1.jpg (272.86 KiB) Viewed 653 times
Fulmar Prion Forty Fours Dave Boyle 2.jpg
Forty Fours Fulmar Prion, Dave Boyle
Fulmar Prion Forty Fours Dave Boyle 2.jpg (207.83 KiB) Viewed 653 times
Fulmar Prion Forty Fours Dave Boyle 3.jpg
Forty Fours Fulmar Prion, Dave Boyle
Fulmar Prion Forty Fours Dave Boyle 3.jpg (273.84 KiB) Viewed 653 times
Last edited by Michael Szabo on Sat Feb 24, 2024 4:55 pm, edited 1 time in total.
'Birds New Zealand' Facebook page: https://www.facebook.com/Birdsnewzealand
User avatar
Michael Szabo
Posts: 2533
Joined: Sun May 08, 2011 12:30 pm
Contact:

Re: Chatham Island Prions

Postby Michael Szabo » Sat Feb 24, 2024 4:04 pm

He also posted these of Pyramid Fulmar Prions, which are a fit for the 'C' type Pyramid Prion we saw.
Fulmar Prion Pyramid Dave Boyle 1.jpg
Pyramid Fulmar Prion, Dave Boyle
Fulmar Prion Pyramid Dave Boyle 1.jpg (314.21 KiB) Viewed 653 times
Fulmar Prion Pyramid Dave Boyle 2.jpg
Pyramid Fulmar Prion, Dave Boyle
Fulmar Prion Pyramid Dave Boyle 2.jpg (213.94 KiB) Viewed 653 times
Fulmar Prion Pyramid Dave Boyle 3.jpg
Pyramid Fulmar Prion, Dave Boyle
Fulmar Prion Pyramid Dave Boyle 3.jpg (227.82 KiB) Viewed 653 times
Last edited by Michael Szabo on Sat Feb 24, 2024 4:55 pm, edited 1 time in total.
'Birds New Zealand' Facebook page: https://www.facebook.com/Birdsnewzealand
User avatar
Michael Szabo
Posts: 2533
Joined: Sun May 08, 2011 12:30 pm
Contact:

Re: Chatham Island Prions

Postby Michael Szabo » Sat Feb 24, 2024 4:57 pm

There is also this photo of a Fairy Prion at Tuku Reserve, main Chatham Island on p166 of Birds of New Zealand: A Photographic Guide, by Paul Scofield and Brent Stephenson. This seems a good fit for the 'A' type prions we saw at sea there.
428650796_7073358262719568_9176364531820894572_n.jpg
428650796_7073358262719568_9176364531820894572_n.jpg (63.4 KiB) Viewed 633 times
'Birds New Zealand' Facebook page: https://www.facebook.com/Birdsnewzealand
User avatar
Michael Szabo
Posts: 2533
Joined: Sun May 08, 2011 12:30 pm
Contact:

Re: Chatham Island Prions

Postby Michael Szabo » Sat Feb 24, 2024 5:06 pm

There are more prion photos from the trip posted with this checklist:
https://ebird.org/atlasnz/checklist/S160467028
'Birds New Zealand' Facebook page: https://www.facebook.com/Birdsnewzealand
User avatar
Michael Szabo
Posts: 2533
Joined: Sun May 08, 2011 12:30 pm
Contact:

Re: Chatham Island Prions

Postby Michael Szabo » Sat Feb 24, 2024 5:09 pm

More prion photos posted with this checklist by Jodi Webber, who was also on the trip:
https://ebird.org/atlasnz/checklist/S160524830
'Birds New Zealand' Facebook page: https://www.facebook.com/Birdsnewzealand
User avatar
Steve Wood
Posts: 382
Joined: Sat Dec 05, 2009 6:57 pm

Re: Chatham Island Prions

Postby Steve Wood » Sat Feb 24, 2024 9:41 pm

Thanks for those pics of Forty Fours Prions Mike, I think you might have joined the dots so to speak. They do look like a good comparison and make a lot of sense. Am I correct in thinking that the Forty fours Pyramid Prions have yet to be officially described ?

Also for the record,you included a pic of assumed Sub- ants Fairy Prion collected at the Tuku reserve. I also found this image amongst the Prion collection which shows similar pale,anaemic head pattens characteristics etc. for this Prion.
IMG_1291.jpeg
IMG_1291.jpeg (428.42 KiB) Viewed 578 times
User avatar
Michael Szabo
Posts: 2533
Joined: Sun May 08, 2011 12:30 pm
Contact:

Re: Chatham Island Prions

Postby Michael Szabo » Sun Feb 25, 2024 8:51 am

According to the paper (Genomic analyses of fairy and fulmar prions reveals parallel evolution of bill morphology and multiple species. Lara D. Shepherd, Colin M. Miskelly, Mariana Bulgarella, Alan J. D. Tennyson), the birds sampled from the Chatham Islands were Fairy Prions from Mangere Island, and Fulmar Prions from both the Pyramid and the Forty Fours (S1 table: https://journals.plos.org/plosone/artic ... ne.0275102).
'Birds New Zealand' Facebook page: https://www.facebook.com/Birdsnewzealand
User avatar
Steve Wood
Posts: 382
Joined: Sat Dec 05, 2009 6:57 pm

Re: Chatham Island Prions

Postby Steve Wood » Sun Feb 25, 2024 4:06 pm

Thanks for the comments. I have attached a couple of images “the Prion “in question,
The “Forty Four Pyramid Prions” documented by Dave Boyle above, highlighting the difference within the Pyramid Prion “Complex” showing the distinction in bill shape in particular. This is a more plausible explanation and seems a clearer and more obvious path to this Prions ID.
Has there been anything mentioned about this variation of the FF Pyramid Prion officially ? (other than in the link that Ian posted).
IMG_1288.jpeg
IMG_1288.jpeg (221.79 KiB) Viewed 494 times

Return to “General Birding Discussion”