Acrocephalus yamashinae (Pagan Reed-warbler)

[sebbe67]

Acrocephalus luscinia yamashinae, also this one are a extinct bird from the Marianna island group, but this subspecies seem to have disapered already in the 1970, it lived on Pagan island is believed to have survived in small numbers until at least the 1960s. The population is now thought to be extirpated, extirpated mean the same as extinct, gone and if the subspecies only lived on this single island it is know extinct, it probably survived into the early 1970. The reason for the extinction are introduced rats, cats and habitat lost.

[sebbe67]

Acrocephalus lusciniayamashinae ofuninhabited Pagan has been little studied, and is known primarily from specimens collected in 1887 and 1931. It is believed to have survived in small numbers until at least the 1960’s (Reichel et al.
1992). Visits to the island during the 1970’s and 1980’s produced no sightings, and a 1981 volcanic eruption destroyed the only known habitat ofthe species when wetlands surrounding the island’s lakes were covered with volcanic debris. The population is now thought to be extinct (Reichel et al. 1992).

[sebbe67]

permanent.access.gpo.gov/websites/fwsgov/ecos.fws.gov/docs/recovery_plans/1998/980410a.pdf

[another specialist]

Past & Present:
Three subspecies of nightingale reed-warbler are currently recognized in the Mariana Islands: Acrocephalus luscinia luscinia (Guam, Saipan, Alamagan), Acrocephalus luscinia nijoi (Aguiguan) and Acrocephalus luscinia yamashinae (Pagan). The validity of these subspecies warrants further study, however.

Of the three recognized subspecies, Acrocephalus luscinia luscinia, originally found on Guam, Saipan, and Alamagan, has been extirpated on Guam since the late 1960s. Acrocephalus luscinia nijoi of the presently uninhabited island of Aguiguan was first reported in 1940 by a Japanese collector, and surveys conducted by the Commonwealth in 1983 and 1985 yielded a maximum count of six individuals. Acrocephalus luscinia yamashinae of uninhabited Pagan has been little studied, and is believed to have survived in small numbers until at least the 1960s. The population is now thought to be extirpated. The total number of nightingale reed-warblers is approximately 6,225-6,230 individuals distributed over three islands: Aguiguan (1-6), Saipan (4,225), and Alamagan (2,000).

Past and present threats to populations include habitat destruction, vulcanism, and introduced predators such as the brown tree snake, rat, and monitor lizard.

www.fws.gov/pacificislands/wesa/nightreedwarb.html

[another specialist]

There are several changes to the Reed-Warblers based on Cibois et al. (2011). The Saipan Reed-Warbler, Acrocephalus hiwae, Pagan Reed-Warbler, Acrocephalus yamashinae, and Mangareva Reed-Warbler, Acrocephalus astrolabii are split from Nightingale Reed-Warbler, Acrocephalus luscinius. Also, the Leeward Islands Reed-Warbler, Acrocephalus musae and Moorea Reed-Warbler, Acrocephalus longirostris are split from Tahiti Reed-Warbler, Acrocephalus caffer. Note that most of these taxa are now extinct. Cibois et al. also added sequenced more of the extant reed-warblers than previously (esp. A. luscinius, syrinx, and rehsei) and the phylogeny has been adjusted accordingly.
[Acrocephalidae, Sylvioidea I, 2.60]

jboyd.net/Taxo/changes.html

[another specialist]

So correct name is Pagan Reed-Warbler, Acrocephalus yamashinae

[Melanie]

Rearrangement of the reed warblers in the Pacific region

Charting the course of reed-warblers
across the Pacific islands
Alice Cibois1*, Jon S. Beadell2, Gary R. Graves3, Eric Pasquet4,5, Beth Slikas6,

si-pddr.si.edu/jspui/bitstream/10088/17642/1/vz_Cibois_et_al_2011_J_Biogeography--Charting_the_course_of_reed-warblers_across_the_Pacific_islands.pdf

[Sebbe]

Nightingale Reed-warbler (Acrocephalus luscinius) is being split: list A. nijoi as Critically Endangered (Possibly Extinct), A. hiwae as Critically Endangered, and A. astrolabii, A. yamashinae and A. luscinius as Extinct?

Pagan Reed-warbler A. yamashinae is also Extinct. On Pagan virtually all vegetative ground cover was effectively removed at certain periods during the 20th century through a variety of agents including human development, introduced feral ungulates and finally a volcanic eruption in 1981 (Reichel et al. 1992). However there had not been any records for some time prior to this, with reports of reed-warblers being present by D. Aldan and J. Sablan into at least the 1960s (Reichel et al. 1992) appearing to be the last observations. Unsuccessful searches took place in the late 1970s (Tenorio and Associates 1979), between 1983 and 1989 (Reichel et al. 1992), in 1999 and 2000 (Division of Fish and Wildlife 2000) and in June 2010 (Marshall and Amidon 2010). The volcanic eruptions in 1981 appear to mark a full stop to the possibility of the species persisting, as all herbaceous and virtually all woody vegetation was destroyed in the last known site, around the upper lake (Reichel et al. 1992).

www.birdlife.org/globally-threatened-bird-forums/2016/10/nightingale-reed-warbler-acrocephalus-luscinius-is-being-split-list-a-nijoi-as-critically-endangered-possibly-extinct-a-hiwae-as-critically-endangered-and-a-astrolabii-a-yamashinae-and-a/

[Peter]

Taxonomy

Kingdom Phylum Class Order Family
Animalia Chordata Aves Passeriformes Acrocephalidae

Scientific Name: Acrocephalus yamashinae
Species Authority: (Taka-Tsukasa, 1931)
Common Name(s):
English – Pagan Reed-warbler
Taxonomic Source(s): del Hoyo, J., Collar, N.J., Christie, D.A., Elliott, A., Fishpool, L.D.C., Boesman, P. and Kirwan, G.M. 2016. HBW and BirdLife International Illustrated Checklist of the Birds of the World. Volume 2: Passerines. Lynx Edicions and BirdLife International, Barcelona, Spain and Cambridge, UK.
Identification information:

Assessment Information

Red List Category & Criteria: Extinct ver 3.1
Year Published: 2016
Date Assessed: 2016-10-01
Assessor(s): BirdLife International
Reviewer(s): Butchart, S. & Symes, A.
Contributor(s): Camp, R., Dutson, G., Freifeld, H., Saunders, A., Radley, P., Mosher, S., Amidon, F. & Gourley, J.
Facilitator/Compiler(s): Benstead, P., Bird, J., Calvert, R., Khwaja, N., Mahood, S., O'Brien, A., Stattersfield, A., Derhé, M., Symes, A., Wright, L & Martin, R
Justification:
The species is considered to have become extinct prior to the 1981 volcanic eruption on Pagan, though this rather destroyed hopes of the species persisting to the current day. Surveys in the 1970s, 1980s, in 2000 and in 2010 all failed to find any trace of the species.

Geographic Range

Range Description: This species is historically known from Pagan in the Northern Mariana Islands (to USA). It probably went extinct in the early 1970s.
Countries occurrence:
Regionally extinct:
Northern Mariana Islands
Additional data:
♦ Continuing decline in area of occupancy (AOO): No
♦ Extreme fluctuations in area of occupancy (AOO): No ♦ Estimated extent of occurrence (EOO) - km2:
♦ Continuing decline in extent of occurrence (EOO): No ♦ Extreme fluctuations in extent of occurrence (EOO): No
♦ Continuing decline in number of locations: No
♦ Extreme fluctuations in the number of locations: No
♦ Upper elevation limit (metres): 500
Range Map: Click here to open the map viewer and explore range.

Population

Population: On Pagan virtually all vegetative ground cover was effectively removed at certain periods during the 20th century through a variety of agents including human development, introduced feral ungulates and finally a volcanic eruption in 1981 (Reichel et al. 1992). However, there had not been any records for some time prior to this, with reports of reed-warblers being present by D. Aldan and J. Sablan into at least the 1960s (Reichel et al. 1992) appearing to be the last observations. Unsuccessful searches took place in the late 1970s (Tenorio and Associates 1979), between 1983 and 1989 (Reichel et al. 1992), in 1999 and 2000 (Division of Fish and Wildlife 2000) and in June 2010 (Marshall and Amidon 2010). The volcanic eruptions in 1981 appear to mark a full stop to the possibility of the species persisting, as all herbaceous and virtually all woody vegetation was destroyed in the last known site, around the upper lake (Reichel et al. 1992).

Trend Justification: Extinct.
Additional data:
♦ Number of mature individuals: 0 ♦ Continuing decline of mature individuals: No
♦ Extreme fluctuations: No ♦ Population severely fragmented: No
♦ No. of subpopulations: 0 ♦ Continuing decline in subpopulations: No
♦ Extreme fluctuations in subpopulations: No ♦ All individuals in one subpopulation: No

Habitat and Ecology

Habitat and Ecology: It was almost exclusively found in freshwater wetland and wetland edge vegetation (Engbring et al. 1982, Reichel et al. 1992, USFWS 1998).
Systems: Terrestrial; Freshwater
Continuing decline in area, extent and/or quality of habitat: No
Movement patterns: Not a Migrant

Citation: BirdLife International. 2016. Acrocephalus yamashinae. The IUCN Red List of Threatened Species 2016: e.T103780103A104319399. Downloaded on 11 December 2016.

www.iucnredlist.org/details/103780103/0

[Sebbe]

Status of endemic reed-warblers of the Mariana Islands, with emphasis on conservation strategies for the endangered Nightingale Reed-warbler.

Insular species, particularly birds, experience high levels of speciation and endemism. Similarly, island birds experience extreme levels of extinction. Based on a 2012 taxonomic assessment, historically there were four reed-warbler species in the Mariana Islands, the Guam Reed-warbler Acrocephalus luscinia (Guam), the Nightingale Reed-warbler Acrocephalus hiwae (Saipan and Alamagan), the Aguijuan Reed-warbler A. nijoi (Aguiguan or Aguijuan), and the Pagan Reed-warbler A. yamashinae (Pagan). Between 2008 and 2010 we surveyed for three of these species on Alamagan, Aguiguan, and Pagan. Our results indicate that reed-warblers are extinct on Aguiguan, likely extinct on Pagan, and only the Nightingale Reed-warbler on Alamagan and Saipan remains. We estimated the global population at between 1,019 and 6,356 birds (95% CI; mean estimate 3,688), which has declined by more than 1,000 birds since the first quantitative surveys were conducted in 1982, i.e. a 24% decline in 28 years. Camp et al. (2009) describe the status of the Nightingale Reed-warbler on Saipan, which has also declined. We estimated the Alamagan population to be between 428 and 1,762 birds in 2010 (mean estimate 946). Thus, the Alamagan population is ~25 % of the global population, and it has declined slightly since 2000. This decline was not significant but is concerning, especially given a similar decline on Saipan. Restoration and protection of tall-stature native and secondary forest could benefit the Alamagan population, as would similar conservation on Saipan that includes wetland habitat. After suitable restoration of forest and wetland habitats on Aguiguan, Guam and Pagan, individuals from Alamagan and Saipan could serve as founder populations. Careful consideration of the extent and habitat preference of individuals translocated to Tinian, where an unknown reed-warbler species previously occurred, is warranted.

www.cambridge.org/core/journals/bird-conservation-international/article/abs/status-of-endemic-reedwarblers-of-the-mariana-islands-with-emphasis-on-conservation-strategies-for-the-endangered-nightingale-reedwarbler/CA910BD726F4F426944C3694F474A899

[Sebbe]

Conservation genomics and systematics of a near-extinct island radiation.

Conservation benefits from incorporating genomics to explore the impacts of population declines, inbreeding, loss of genetic variation and hybridization. Here we use the near-extinct Mariana Islands reedwarbler radiation to showcase how ancient DNA approaches can allow insights into the population dynamics of extinct species and threatened populations for which historical museum specimens or material with low DNA yield (e.g., scats, feathers) are the only sources for DNA. Despite their having paraphyletic mtDNA, nuclear SNPs support the distinctiveness of critically endangered Acrocephalus hiwae and the other three species in the radiation that went extinct between the 1960s and 1990s. Two extinct species, A. yamashinae and A. luscinius, were deeply divergent from each other and from a third less differentiated lineage containing A. hiwae and extinct A. nijoi. Both mtDNA and SNPs suggest that the two isolated populations of A. hiwae from Saipan and Alamagan Islands are sufficiently distinct to warrant subspecies recognition and separate conservation management. We detected no significant differences in genetic diversity or inbreeding between Saipan and Alamagan, nor strong signatures of geographic structuring within either island. However, the implications of possible signatures of inbreeding in both Saipan and Alamagan, and long-term population declines in A. hiwae that predate modern anthropogenic threats require further study with denser population sampling. Our study highlights the value conservation genomics studies of island radiations have as windows onto the possible future for the world’s biota as climate change and habitat destruction increasingly fragments their ranges and contributes to rapid declines in population abundances.

onlinelibrary.wiley.com/doi/10.1111/mec.16382

[Sebbe]

Untangling the colonization history of the Australo-Pacific reed warblers, one of the world’s great island radiations.

Island radiations, such as those of the Australo-Pacific, offer unique insight into diversification, extinction, and early speciation processes. Yet, their speciation and colonization histories are often obscured by conflicting genomic signals from incomplete lineage sorting or hybridization. Here, we integrated mitogenomes and genome-wide SNPs to unravel the evolutionary history of one of the world’s most geographically widespread island radiations. The Australo-Pacific reed warblers (Acrocephalus luscinius complex) are a speciose lineage including five species that have become extinct since the 19th century and ten additional species of conservation concern. The radiation spans over 10,000 km across Australo-Papua, Micronesia and Polynesia, including the Mariana, Hawaii and Pitcairn Island archipelagos. Earlier mtDNA studies suggested a stepping-stone colonization process, resulting in archipelago-level secondary sympatry of divergent mtDNA lineages in the Mariana Islands and Marquesas. These studies hypothesised that morphologically similar species on neighbouring islands arose from ecological convergence. Using hDNA from historical museum specimens and modern genetic samples, we show that incomplete lineage sorting and/or gene flow have shaped the radiation of Australo-Pacific reed warblers rather than secondary sympatry. The nuclear genome reconstructs a simpler biogeographic history than mtDNA, showing close relationships between species in the Mariana Islands and Marquesas despite their paraphyletic mtDNA lineages. Gene flow likely involved early and late colonizing waves of the radiation before the loss of ancestral dispersive ability. Our results highlight how collection genomics can elucidate evolutionary history and inform conservation efforts for threatened species.

academic.oup.com/evolut/advance-article/doi/10.1093/evolut/qpae136/7759539?login=false