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Laridae (1 Viewer)
- Thread starter Richard Klim
- Start date
Kirk Roth
Rarely to be taken seriously
These would be the White, Atlantic, and Little Manu-o-Ku, based on priority of the earliest known common name for these taxa. So there is a need for two hyphens apiece. But it solves all possible common name problems whatsoever, including confusion with the noddies, Fairy Tern, and Common Tern.
Nutcracker
Stop Brexit!
A Polynesian name I presume? What's the etymology?
Jim LeNomenclatoriste
Je suis un mignon petit Traquet rubicole
birdboybowley
Well-known member.....apparently so ;)
Call them Angel Terns. To me Fairy (or Faerie even) fits them perfectly.....White Tern is just so.....boring!!
As for the Fairy Tern now....it's Australsian Little Tern on my list coz that's basically what it is
As for the Fairy Tern now....it's Australsian Little Tern on my list coz that's basically what it is
Markus Lagerqvist
Well-known member
As for the Fairy Tern now....it's Australsian Little Tern on my list coz that's basically what it is
That's the translation of the official Swedish name, i.e. Australian Little Tern, solves the problem, so fairy can be used for the Gygis species.
Murray Lord
Well-known member
It’s always been a mystery why the white birds aren’t called Ternlets like the grey ones. Maybe now is the time.
Peter Kovalik
Well-known member
Marleen Baling, Dianne Brunton. Structured phylogeography and restricted gene flow among populations of Fairy Tern (Sternula nereis) across Australasia: implications for the endangered New Zealand population. Ibis, First published: 26 January 2022 https://doi.org/10.1111/ibi.13048
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.
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.
albertonykus
Well-known member
Schlesselmann, A.-K.V., J. Cooper, N. Dussex, and B.C. Robertson (2022)
New Zealand endemic open-habitat specialist, the Black-fronted Tern (Chlidonias albostriatus), experienced population expansion during Pleistocene glaciation and recent decline
Ibis (advance online publication)
doi: 10.1111/ibi.13107
Understanding how climatic and environmental changes, as well as human activities, induce changes in distribution and population size of avian species refines the ability to predict future impacts on threatened species. Using multilocus genetic data, we show that the population of a threatened New Zealand endemic open-habitat specialist, the Black-fronted Tern Chlidonias albostriatus – in contrast to forest specialists – expanded during the last glacial period. The population has decreased subsequently despite the availability of extensive open habitat after human arrival to New Zealand. We conclude that population changes for open habitat specialist such as Black-fronted Terns in pre-human New Zealand were habitat dependent, similar to Northern Hemisphere cold-adapted species, while post human settlement populations were constrained by predators independent of habitat availability similar to other island endemic species.
New Zealand endemic open-habitat specialist, the Black-fronted Tern (Chlidonias albostriatus), experienced population expansion during Pleistocene glaciation and recent decline
Ibis (advance online publication)
doi: 10.1111/ibi.13107
Understanding how climatic and environmental changes, as well as human activities, induce changes in distribution and population size of avian species refines the ability to predict future impacts on threatened species. Using multilocus genetic data, we show that the population of a threatened New Zealand endemic open-habitat specialist, the Black-fronted Tern Chlidonias albostriatus – in contrast to forest specialists – expanded during the last glacial period. The population has decreased subsequently despite the availability of extensive open habitat after human arrival to New Zealand. We conclude that population changes for open habitat specialist such as Black-fronted Terns in pre-human New Zealand were habitat dependent, similar to Northern Hemisphere cold-adapted species, while post human settlement populations were constrained by predators independent of habitat availability similar to other island endemic species.
albertonykus
Well-known member
Given, A.D., J.A. Mills, P. Momigliano, and A.J. Baker (2022)
Molecular evidence for introgressive hybridization in New Zealand masked gulls
Ibis (advance online publication)
doi: 10.1111/ibi.13117
We used mitochondrial DNA gene sequences and nuclear microsatellite loci to investigate the extent and outcome of hybridization between the Black-billed Gull Chroicocephalus bulleri and the Red-billed Gull Chroicocephalus novaehollandiae scopulinus in New Zealand. Six of 26 sampled Black-billed Gulls possessed mitochondrial DNA typical of Red-billed Gulls, but allele frequencies at six polymorphic microsatellites provide little evidence of mixed ancestry expected in very recent hybrids. None of the Red-billed Gulls sampled from different colonies possessed Black-billed Gull mitochondrial DNA expected in the reciprocal cross, suggesting that hybridization in the two species typically occurs between female Red-billed Gulls and Black-billed Gull males. The lack of any hybrid signal in the nuclear loci indicates that there has been extensive backcrossing with Black-billed Gulls, effectively diluting the Red-billed Gull nuclear DNA contribution. Divergence of Red-billed Gulls and Black-billed Gulls occurred approximately 250 000 years ago, indicating that unsorted ancestral polymorphism is an unlikely alternative to hybridization. Comparing demographic models within an approximate Bayesian computation (ABC) framework, we confirm that the observed patterns cannot result from incomplete lineage sorting. Using an ABC random forest approach, we determined that the most likely model explaining the data is a recent introgression scenario, whereby unidirectional gene flow is re-established following a period of strict isolation. The ability of Black-billed and Red-billed Gulls to successfully interbreed shows that despite significant differentiation (FST > 0.3), there has been insufficient time for the two species to develop complete reproductive isolation. The apparent one-way transfer of Red-billed Gull mtDNA into Black-billed Gulls and extensive backcrossing argues against cytoplasmic-nuclear genome incompatibilities between the two species. We hypothesize that the specific mate recognition system cued on colours of soft parts normally functions to prevent hybridization, but that it can break down under demographic conditions where there is a shortage of available mates and a surplus of females in the Red-billed Gull population. The high incidence of introgression in Black-billed Gulls conflicts with field observations that show that interbreeding is extremely rare.
Molecular evidence for introgressive hybridization in New Zealand masked gulls
Ibis (advance online publication)
doi: 10.1111/ibi.13117
We used mitochondrial DNA gene sequences and nuclear microsatellite loci to investigate the extent and outcome of hybridization between the Black-billed Gull Chroicocephalus bulleri and the Red-billed Gull Chroicocephalus novaehollandiae scopulinus in New Zealand. Six of 26 sampled Black-billed Gulls possessed mitochondrial DNA typical of Red-billed Gulls, but allele frequencies at six polymorphic microsatellites provide little evidence of mixed ancestry expected in very recent hybrids. None of the Red-billed Gulls sampled from different colonies possessed Black-billed Gull mitochondrial DNA expected in the reciprocal cross, suggesting that hybridization in the two species typically occurs between female Red-billed Gulls and Black-billed Gull males. The lack of any hybrid signal in the nuclear loci indicates that there has been extensive backcrossing with Black-billed Gulls, effectively diluting the Red-billed Gull nuclear DNA contribution. Divergence of Red-billed Gulls and Black-billed Gulls occurred approximately 250 000 years ago, indicating that unsorted ancestral polymorphism is an unlikely alternative to hybridization. Comparing demographic models within an approximate Bayesian computation (ABC) framework, we confirm that the observed patterns cannot result from incomplete lineage sorting. Using an ABC random forest approach, we determined that the most likely model explaining the data is a recent introgression scenario, whereby unidirectional gene flow is re-established following a period of strict isolation. The ability of Black-billed and Red-billed Gulls to successfully interbreed shows that despite significant differentiation (FST > 0.3), there has been insufficient time for the two species to develop complete reproductive isolation. The apparent one-way transfer of Red-billed Gull mtDNA into Black-billed Gulls and extensive backcrossing argues against cytoplasmic-nuclear genome incompatibilities between the two species. We hypothesize that the specific mate recognition system cued on colours of soft parts normally functions to prevent hybridization, but that it can break down under demographic conditions where there is a shortage of available mates and a surplus of females in the Red-billed Gull population. The high incidence of introgression in Black-billed Gulls conflicts with field observations that show that interbreeding is extremely rare.
Jacana
Will Jones
I disagree with their last sentence of the abstract (I will read the paper more thoroughly when I'm back from my holidays). It is perfectly possible to have signals of extensive introgression in a population while also having low levels of mixed-pair matings.
There's a great mammal example of this in Scotland with extensive introgression of Sika genes in parts of the Red Deer population, yet indepth sequencing has shown that all of this has only come from something <10 hybridisation events. (Tracking down the citation for this now)
There's a great mammal example of this in Scotland with extensive introgression of Sika genes in parts of the Red Deer population, yet indepth sequencing has shown that all of this has only come from something <10 hybridisation events. (Tracking down the citation for this now)
I was thinking along these same lines. Are they really reporting the early stages of a mitochondrial DNA sweep?
Niels
Jacana
Will Jones
Byerly, P.A., Chesser, R.T., Fleischer, R.C. et al. Conservation genomics reveals low connectivity among populations of threatened roseate terns (Sterna dougallii) in the Atlantic Basin. Conservation Genetics (2023). https://doi.org/10.1007/s10592-023-01505-6
While the effects of barriers to dispersal such as population declines, habitat fragmentation, and geographic distance have been well-documented in terrestrial wildlife, factors impeding the dispersal of highly vagile taxa such as seabirds are less well understood. The roseate tern (Sterna dougallii) is a globally distributed seabird species, but populations tend to be both fragmented and small, and the species is declining across most of its range. We evaluated structuring of roseate tern populations in the Northwestern Atlantic, the Caribbean, and the Azores using both microsatellite markers and single-nucleotide polymorphisms generated through targeted sequencing of Ultra-conserved Elements. For both marker types, we found significant genetic differentiation among all 3 populations and evidence for moderate contemporary unidirectional gene flow from the Caribbean to the Azores, but not between other populations. Within the Caribbean population, we found high rates of unidirectional migration from the Virgin Islands to Florida, potentially indicative of movement from source population to sink or an artifact of dispersal among other unsampled populations in the Caribbean region. These observations have significance for species persistence in the Atlantic, as our results indicate that loss of genetic diversity within populations is unlikely to be buffered by inflow of new alleles from other breeding populations.
While the effects of barriers to dispersal such as population declines, habitat fragmentation, and geographic distance have been well-documented in terrestrial wildlife, factors impeding the dispersal of highly vagile taxa such as seabirds are less well understood. The roseate tern (Sterna dougallii) is a globally distributed seabird species, but populations tend to be both fragmented and small, and the species is declining across most of its range. We evaluated structuring of roseate tern populations in the Northwestern Atlantic, the Caribbean, and the Azores using both microsatellite markers and single-nucleotide polymorphisms generated through targeted sequencing of Ultra-conserved Elements. For both marker types, we found significant genetic differentiation among all 3 populations and evidence for moderate contemporary unidirectional gene flow from the Caribbean to the Azores, but not between other populations. Within the Caribbean population, we found high rates of unidirectional migration from the Virgin Islands to Florida, potentially indicative of movement from source population to sink or an artifact of dispersal among other unsampled populations in the Caribbean region. These observations have significance for species persistence in the Atlantic, as our results indicate that loss of genetic diversity within populations is unlikely to be buffered by inflow of new alleles from other breeding populations.
Brian J Small
Well-known member
A new subspecies of Little Tern Sternula albifrons levantinus is described in the recent British Birds:
britishbirds.co.uk
The paper describes plumage differences, notably tone of upperparts, extensive grey rump and number of dark outer primares. I did a bit of citizen science and looked at photos from Israel on eBird between March and July. Virtually all had just 2 dark outer primaries and just a handful had more.
media.ebird.org
Ringed bird from study area, with just 2 dark outer primaries - typical - ML447197981 Little Tern Macaulay Library
Ringed bird from study area with 5 dark outer primaries - ML250281951 Little Tern Macaulay Library
Brian
A new subspecies of Little Tern from the Levant and its distinction from ‘European Little Tern’ and Saunders’s Tern
Abstract In this paper, we describe a new subspecies of the Little Tern Sternula albifrons. We propose the name S. a. levantinus, the ‘Levant Little Tern’, reflecting the known breeding range of these birds. Levant Little Terns are, compared to Little Terns elsewhere in Europe (‘European Little...
britishbirds.co.uk
The paper describes plumage differences, notably tone of upperparts, extensive grey rump and number of dark outer primares. I did a bit of citizen science and looked at photos from Israel on eBird between March and July. Virtually all had just 2 dark outer primaries and just a handful had more.
Little Tern - Sternula albifrons - Media Search - Macaulay Library and eBird
Explore millions of photos, audio recordings, and videos of birds and other animals; powered by Macaulay Library and eBird. The Macaulay Library collects, archives, and distributes wildlife media for research, education, and conservation.
Ringed bird from study area, with just 2 dark outer primaries - typical - ML447197981 Little Tern Macaulay Library
Ringed bird from study area with 5 dark outer primaries - ML250281951 Little Tern Macaulay Library
Brian
l_raty
laurent raty
Brian,
Terns primaries darken with time. The number of dark outer primaries in a spring bird is actually (at least in part) the result of a moult limit (i.e., not really a difference in plumage), separating dark, older outer primaries (which date from the previous -- usually complete -- post-breeding moult), from paler, fresher inner primaries (which were replaced again as part of the last -- usually partial -- pre-breeding mout).
While the pic in the first link above shows a spring bird with no visible active moult, the pic in the second link shows a mid-summer bird in active primary moult: pp1-4 are new, with p4 possibly not fully grown yet (distance p2-p3 longer than p3-p4); p5 is not visible (either lacking, or just starting to grow); pp6-10 are indeed rather dark... P10, however, seems somewhat darker than the others, and its tip looks more worn.
I would expect this second bird to have had only one dark outer primary in the previous spring.
Terns primaries darken with time. The number of dark outer primaries in a spring bird is actually (at least in part) the result of a moult limit (i.e., not really a difference in plumage), separating dark, older outer primaries (which date from the previous -- usually complete -- post-breeding moult), from paler, fresher inner primaries (which were replaced again as part of the last -- usually partial -- pre-breeding mout).
While the pic in the first link above shows a spring bird with no visible active moult, the pic in the second link shows a mid-summer bird in active primary moult: pp1-4 are new, with p4 possibly not fully grown yet (distance p2-p3 longer than p3-p4); p5 is not visible (either lacking, or just starting to grow); pp6-10 are indeed rather dark... P10, however, seems somewhat darker than the others, and its tip looks more worn.
I would expect this second bird to have had only one dark outer primary in the previous spring.
Last edited:
James Lowther
Well-known member
Re: Levantine little tern. Is the whole abstract available to read (for free!) anywhere?
Cheers
James
Cheers
James
JustinJansen
Well-known member
How large is their sample, and do they show the variation in all species?
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