Fairy Tern - Structured phylogeography and restricted gene flow among populations of Fairy Tern across Australasia

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Michael Szabo
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Fairy Tern - Structured phylogeography and restricted gene flow among populations of Fairy Tern across Australasia

Postby Michael Szabo » Fri Jan 28, 2022 7:21 am

Abstract: The Fairy Tern Sternula nereis is an Australasian tern that breeds in Australia, New Caledonia and New Zealand, with the latter having the smallest breeding population and is listed as ‘Threatened – Nationally Critical’ by the New Zealand Department of Conservation. Here, we investigate the genetic relatedness and level of endemism (gene flow) of the New Zealand Fairy Tern S. n. davisae population compared to the larger breeding populations in Australia S. n. nereis and New Caledonia S. n. exsul using the NADH subunit 2 (ND2) region of the mitochondrial DNA. We found that the three main populations (n = 86) were genetically distinct with a different fixed haplotype restricted to New Zealand (n = 15) and New Caledonia (n = 16), and that the estimated gene flow was low to zero, indicating no interbreeding between the populations. The current genetic evidence is consistent with observations of morphological and behavioural differences among the populations, and we suggest continued independent management of the population in New Zealand and further surveys and independent management of the New Caledonia population.

Link: https://onlinelibrary.wiley.com/doi/10. ... svy2mlB2hw
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Re: Fairy Tern - Structured phylogeography and restricted gene flow among populations of Fairy Tern across Australasia

Postby fras444 » Fri Feb 11, 2022 1:30 pm

I do find this read quite interesting and along with that article regarding the Red-billed gulls.

I am incredibly fascinated Sub-species and with this grey zone being "Sub-species/native-endemics" and how far do the likes of DOC go towards supporting a subspecies with the slightest genetic variations bearing in mind the flow of those genetics between those Sub-species and at what stage do we call a subspecies unique and give it the highest honor of being an endemic (found nowhere else or in birds terms... breeding only in NZ.... i.e Long-tailed cuckoo)

For the likes of the Grey duck and the Shoveler (Two which have been described in the past as potential subspecies) which are quite mobile birds where there is a high potential of genetic flow/interbreeding which would have (I guessed) explained why these birds are no longer described as being subspecies..

I do feel, regardless of how small that difference is between identified subspecies, we should be doing (like what we are currently doing with the Fairy Tern) doing everything in our disposal and committing as much $$ as we can to ensure the safe guard of our subspecies that are in a critical status.

I feel that, through the current list of subspecies (even our own endemic species that could be a subspecies within.. Blue Shag) we are seeing in motion a species adapting to it's new surrounds thus through the 1000s of years adapting and evolving towards becoming it's own species outright. We should be dedicating more research into those subspecies, discovering how far they have gone on that journey and just how different they actually are to their Australian counterpart and thus identify just how much funding one receives if in a critical status.
"It's alright there are plenty in Australia..." "They will come back again"

At the end of the day...

If the Pied shag, Grey Duck, Fairy tern or the Kingfisher were to become extinct in NZ (four birds that basically cover that whole subspecies spectrum..)
Would brining in birds from Australia ever be the same vs a species that has been here for 1000s of years would we be losing something genetically unique that will forever be lost.

Cause these birds are already and will become our future kiwis or Kakapo

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