Archived 2021 topic: Black-winged Myna (Acridotheres melanopterus): Revise global status?

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10 Responses to Archived 2021 topic: Black-winged Myna (Acridotheres melanopterus): Revise global status?

  1. James Eaton says:

    There have been very few records from Alas Purwo National Park, for several years now, with a maximum of just three birds last year by Hery Kusumanegara, who visits several times during each month of the year for birding. The rangers on-site have yet to see the species this year.

    At Bali Barat National Park and surrounding area, the March 2021 census by the park rangers revealed a total of just 109-114 in four sub-populations (31, 22-27, 33 and 23 individuals) (Hery Kusumanegara, BBNP head ranger, pers comm). Poaching is still present inside the park, with three juveniles poached as recently as May 2021, after a good breeding season inside the park.

    James

  2. Just a quick recap of conditions from a few years back based on observation submitted through Burungnesia (2021) otherwise noted:

    A. m. melanopterus:
    Two individuals were reported from TWA Muara Angke in May 2021 by Marzuki Fathur Rohman, but this is most likely part of 65 individuals released by KLHK in the same month (KLHK, 2021) after the last 2 individuals that were regularly seen went missing since 2017 (Boas Emmanuel, Khaleb Yordan & Desi Ayu Triana, pers comm).

    A. m. tricolor:
    Population in Baluran is virtually increasing, with up to 98 individuals counted in a single roost count in September 2018 (pers. obs). Thomas Squires may have a more thorough population estimate from this area in his study.
    As said by James, the population in Alas Purwo might have been decimated–with only 5 observations between 2017-2019 comprised of only 1-2 individuals; the last observations of 2 individuals were submitted in June 2019 by Happy Ferdiansyah.
    No sightings were submitted from Meru Betiri.

    A. m. tertius:
    7 observation submitted from Bali Barat National Park between 2018-2019 in 4 location, comprised of 2-8 individual; but I believe it is severely underreported and the BBNP’s cencus as mentioned by James represent well the current condition of its population in the area.
    Only 1 observation submitted from Nusa Penida by Ardi Wiranata in 2019, but this also might be severely underreported.
    In Uluwatu 6 were reported from in February 2021 by Fathur Rohman, but sightings from this area is regularly reported since 2019 (Muhammad Saifudin, pers comm.). Poaching is present in this area with a single poacher reported to trap several juvenile each year (Muhammad Saifudin, pers comm).

  3. Although subspecies are not usually considered in the global red list assessment of birds I think it is worth mentioning that (Sadanandan et al. 2020) credited for the re-lumping of the Black-winged Myna complex in the assessment above, argues for treating the three taxa as separate conservation units. In the light of the lumped populations nearly fulfilling the threshold for CR under criterion C, I think this observation should be given weight and in this case the species maintained under CR status.

    Some additional observations on the subspecies:

    A. m. melanopterus:
    At the Bogor Taman Safari facilities, a trial release on grounds have seen a growing population since 2016 peaking at around free-flying 55 birds in 2020, but dropped to less than 25 birds in 2021 due to a localized storm which dispersed or killed a portion of the population. The birds are breeding in the wild in natural and artificial nesting cavities and are to a degree subject to supplemental feeding. There is an ongoing monitoring and community engagement preventing trapping on grounds and in most surrounding areas. Trapping interest have however been recorded at the fringe of the area (Jochen Menner, KASI Foundation, pers comm).

    A. m. tricolor:
    We did a study of the online trade in Eastern Java between April 2020 and March recording a minimum of 19 Grey-backed Mynas offered for sale on social media with indications of these being sourced in the Baluran NP. Sixteen different sellers were identified, suggesting that most of the sales were conducted opportunistically. The research was not in depth so the birds identified in the online trade may only represent a fraction of the birds actually trafficked in this time period making it plausible that more than 10% of the BNP population of Grey-backed Mynas have been poached in the past year (Bruslund et al. Online trade records of Grey-backed Myna Acridotheres tricolor indicate poaching practices in Baluran National Park, Indonesia in litt in next issue of Birding Asia) based on the recent population estimated for Baluran NP by Squires et al. in litt.

    A. m. tertius:
    Just adding to the discussion Brillianti et al. suggested in 2019 that the population in Bali Barat NP was limited to 35 mature individuals (Brillianti et al. POPULASI DAN HABITAT JALAK PUTIH (Sturnus melanopterus Daudin 1800) DI TAMAN NASIONAL BALI BARAT, JPSL Vol. 9 (1): 97-105 Mach 2019 http://journal.ipb.ac.id/index.php/jpsl/article/download/19404/16628

  4. Khaleb Yordan says:

    more information for A.m.melanopterus based on my observations during my birding trips:

    – No sightings at Pulau Dua, Banten during my birding trips 2017-2019
    – and the last individual at Muara Angke was observed in the end of 2019 and then no more sightings

  5. Red List Team (BirdLife International) says:

    Many thanks to everyone who has contributed to this discussion. We greatly appreciate the time and effort invested by so many people in commenting. The window for consultation is now closed. We will analyse and interpret the new information and post a preliminary decision on this species’s Red List status on this page in early July.

    Thank you once again,
    BirdLife Red List Team

  6. Red List Team (BirdLife International) says:

    Preliminary proposal

    Based on available information, our preliminary proposal for the 2021 Red List would be to adopt the proposed classifications outlined in the initial forum discussion.

    Further information has been supplied on the current size of the populations in Baluran NP and on Bali, with thanks to Tom Squires, Stuart Marsden and David Jeggo. In agreement with the estimate of 35 individuals in Bali Barat National Park (Brillianti et al. 2019) as highlighted by Simon Brusland above, the recent correspondence expressed surprise that there could be more than 100 individuals across the whole of Bali, with fewer than 50 believed to be within Bali Barat National Park (T. Squires & S. Mardsen in litt. 2021). As such, the lower bound for this subpopulation is considered to plausibly fall below 50 mature individuals. However, the population in Baluran has been well-protected recently (despite recent observations of the poaching of juveniles) and totals c. 180 birds (Squires et al. in press, T. Squires in litt. 2021). With greater than 50 mature individuals estimated to be present here, despite the rapid recent loss of birds from elsewhere in the range of A. m. tricolor the subcriterion for listing under Criterion C continues to be met at the level of Endangered.

    There is now a period for further comments until the final deadline in mid-July, after which the recommended categorisations will be put forward to IUCN.

    The final 2021 Red List categories will be published on the BirdLife and IUCN websites in December 2021, following further checking of information relevant to the assessments by both BirdLife and IUCN.

  7. I acknowledge the proposed assessment of EN but would like to remark that a decline rate which would lead to CR under criterion C1 is effectively only prevented due to the population at this point in time primarily survive in protected areas, demonstrating the immense importance of ongoing protection enforcement in these localities.

    • Red List Team (BirdLife International) says:

      This is absolutely true: the work done to date (notably in Baluran) must be given credit and must be supported fully to continue.

  8. James Eaton says:

    ‘In agreement with the estimate of 35 individuals in Bali Barat National Park (Brillianti et al. 2019) as highlighted by Simon Brusland above, the recent correspondence expressed surprise that there could be more than 100 individuals across the whole of Bali, with fewer than 50 believed to be within Bali Barat National Park’ – does this mean observers are refuting the evidence and census provided by the Bali Barat park rangers of 109-114 birds in four sub-populations being present?

  9. Red List Team (BirdLife International) says:

    Recommended categorisation to be put forward to IUCN

    The final categorisation for this species has changed. Black-winged Myna is now recommended to be listed as Endangered under Criteria C2a(i); D.

    Many thanks for everyone who contributed to the 2021 GTB Forum process. The final 2021 Red List categories will be published on the BirdLife and IUCN websites in December 2021, following further checking of information relevant to the assessments by both BirdLife and IUCN.

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