Archived 2012-2013 topics: Black-crowned Barwing (Actinodura sodangorum): downlist to Near Threatened?

BirdLife species factsheet for Black-crowned Barwing Black-crowned Barwing Actinodura sodangorum occurs in Vietnam and Laos. It is currently listed as Vulnerable under criteria B1ab(i,ii,iii,iv,v) because it was known from only 2 areas,  assumed to have a small range and population, and thought likely to be undergoing a continuing decline owing to widespread habitat loss and deforestation across its projected range. It was previously known from just seven associated localities in Kontum province in the western highlands of Vietnam, and one locality on the Dakchung Plateau, Xe Kong province in south-east Laos (BirdLife International 2001). However, it was recently discovered at approximately 1700m in western Xe Sap in Laos (T. Gray in litt. 2012), although it was not recorded elsewhere during play-back surveys and suitable habitat above 1500m is limited in the Xe Sap NPA (T. Gray in litt. 2012). Thus, it has been suggested that the population size is likely to be higher than the current estimate of 1,500-7,000 mature individuals (S. Mahood in litt. 2012). Also, despite its poorly known range, the population may not be in continuing decline; it may actually favour the loss of primary forest, and although some of the forest areas have been completely converted to agriculture, the human population density is low enough for field margins and forest patches to persist (S. Mahood in litt. 2012). If there is sufficient reason to suggest that this species is not restricted to ≤10 locations and/or the population, area and extent of occurrence and area, extent and/or quality of the species’s habitat is not in continuing decline, this species could warrant downlisting to Near Threatened, approaching the thresholds for Vulnerable under criteria B1ab(i,ii,iii,iv,v) of the IUCN Red List. Further information is required on this species’s estimated population size, distribution, range, trends and habitat requirements. Any additional comments on the proposed downlisting are also welcome.  Reference: BirdLife International (2001) Threatened birds of Asia: the BirdLife International Red Data Book. BirdLife International: Cambridge, U.K.

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6 Responses to Archived 2012-2013 topics: Black-crowned Barwing (Actinodura sodangorum): downlist to Near Threatened?

  1. Tom Gray says:

    In addition to the record mentioned above in Xe Sap NPA was recorded by RJ Timmins and N Wilkinson from similar habitat [c.1300-m.a.s.l.] in Kaleum district S of Xe Sap NPA border in May 2012. These two sites, and the other Laos location on the Dakchung Plateau, are quite well separated with considerable suitable habitat in between. However the 2012 surveys [140 survey man days] only recorded black-crowned barwing on these 2 occasions; considerably fewer records than for chesnut-eared laughingthrush.

    Our Xe Sap survey report (in prep) says:
    “Records of the species from three distinct locations in hill evergreen and Ericaceous cloud forest in Xekong and Salavan provinces suggest this assertion [not uncommon within its known range and is likely to occur in a numbers of locations in south-east Laos (Xekong and Attapu provinces) and in Quang Nam province, Vietnam] is correct and it is likely that the greater Xe Sap region supports a significant proportion of the global population of black-crowned barwing. Studies into the extent and rates of forest loss and degradation are necessary to identify whether the species meets the criteria for classification as IUCN Vulnerable (e.g. global range <20,000-km2 and on-going decline in range due to habitat loss)."

    Any change in status of this species should, I imagine, also affect chestnut-eared laughingthrush.

  2. The categorisation as VU always struck me as precautionary given the relative wealth of suitable habitat in Lao PDR (I agree with the statement above that suitable habitat might – temporarily – be increasing for the species in Lao) and the very little search effort put into looking for the species. I think it would be fairly tricky to get meaningful info on the rate of habitat change relevant to this species. However, as the recent Xe SAp survey in Lao did not find evidence for a broad distribution, perhaps it might be premature to change the category to NT on the assumption that it is ‘obviously’ present in more than 10 localities and simply not yet found. Perhaps there are unsuspected subtelties in the species’s occupation of habitat. It’s confusing for everyboy to have changes of category and I could see an argument for keeping it as VU pending further info (tho personally feel LC/NT would be more likely to be the ‘real categories).

  3. John Pilgrim says:

    WD’s comments are sensible – there seems no reason for this species not to thrive in secondary forest and patchy forest within agriculture (the habitats in which the species is most often seen), yet it remains restricted in range… there appears to be some non-obvious limiting factor, and so a precautionary approach would be advisable.

  4. Craig Robson says:

    I have no idea why this species was given any threat category, and I would de-list it completely.

  5. R. J. Timmins says:

    Having now seen it in Laos I would downlist the species, as in all probability the species probably prefers disturbed habitats over ‘undisturbed’ ones (where I spend the majority of my time) [contra Tom’s comments above]. I can not see good grounds for taking a precautionary approach that would also be parsimonious with the listings of comparable species.

  6. R. J. Timmins says:

    I think I wasn’t very clear in my previous comment. Tom’s comment about Xe Sap is only half the picture.

    I spent less than a day in secondary/degraded habitat and in that ‘less than a day’ found two groups at two seperate locations. By contrast the remaining four weeks of my time was spent in mature ‘primary’ forest and I only recorded chesnut-eared laughingthrush at a rate less than every other day. So to conclude that the barwing is more localised and or scarcer than the laughingthrush, follows no logic.

    The species appears to be genuinely localised in ‘mature’ forest and certainly in it’s Lao range favouring secondary and degraded forest formations (dakchung and Kaleum records are not even close to remaining areas of ‘mature forest’).

    Furthermore to list the species under the B1a criteria is unjustified – there is absolutely no evidence(even speculative) to my knowledge that there is any decline in habitat quality or extent, or any change in the species population numbers, range etc.
    There are no sites at which the species has disappeared and it is mature forest rather than degraded and secondary formations that are being lost at the high altitudes at which the species has been found. There is turn-over in secondary and degraded forest, but if it were not for human disturbance such forest would naturally be very limited in extent. I don’t see any significant net change to date.

    Flip-flopping in categories is unhelpful, but so also is alarmism.

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