Rusty Laughingthrush (Garrulax poecilorhynchus): uplist to Near Threatened or Vulnerable?

This discussion was first published as part of the 2013 Red List update, but remains open for comment to enable reassessment in 2014.

BirdLife species factsheet for Rusty Laughingthrush

Rusty Laughingthrush Garrulax poecilorhynchus is restricted to Taiwan (China). It is currently listed as Least Concern because it was not thought to approach the thresholds for Vulnerable under any of the IUCN Red List criteria. It was thought to have very large range, and hence did not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence [EOO] <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). Despite the fact that the population trend appeared to be decreasing, the decline was not believed to be sufficiently rapid to approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size has not been quantified, but it was not believed to approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure).

However, recent mapping of this species’s range shows that its EOO is approximately 17,800km2. Also, its population is suspected to be in decline owing to on-going habitat destruction and fragmentation. If this information is confirmed, and the EOO of this species is <20,000km2, it is inferred to be in continuing decline owing to habitat loss, and it is found at ≤10 locations or severely fragmented, it would warrant uplisting to Vulnerable under criterion B1ab(i,ii,iii,v). If these thresholds were approached but not all met, uplisting to Near Threatened may be appropriate.

The term ‘location’ defines a geographically or ecologically distinct area in which a single threatening event can rapidly affect all individuals of the taxon present. The size of the location depends on the area covered by the threatening event and may include part of one or many subpopulations. Where a taxon is affected by more than one threatening event, location should be defined by considering the most serious plausible threat. (IUCN 2001). For example, where the most serious plausible threat is habitat loss, a location is an area where a single development project can eliminate or severely reduce the population. Where the most serious plausible threat is volcanic eruption, hurricane, tsunami, frequent flood or fire, locations may be defined by the previous or predicted extent of lava flows, storm paths, inundation, fire paths, etc.

Information is requested on the population size, trends and distribution of this species, the number of locations at which it occurs and the degree to which the population is fragmented.

Related posts:

  1. Archived 2012-2013 topics: Rufous-fronted Laughingthrush (Garrulax rufifrons): uplist to Vulnerable?
  2. Archived 2011-2012 topics: Chinese Hwamei (Garrulax canorus): request for information
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3 Responses to Rusty Laughingthrush (Garrulax poecilorhynchus): uplist to Near Threatened or Vulnerable?

  1. Joe Taylor says:

    The following comments were received from Kuan-Chieh Hung on 5 February 2014:

    I am a staff work in Chinese Wild Bird Federation (BirdLife in Taiwan). In Taiwan we has run Breeding Bird Survey (BBS) since 2009, so far we has reviewed the data till 2012. Our plot is 6-10 small point count plots (radius 100m) in about 1 square km. In the first year we have only 101 plots, in 2012 we have 253 plots and in 2013 we have 311 plots. Therefore, we can use the BBS data to estimate the population size of breeding birds (especially endemic species) of Taiwan. The key analysis of BBS is focus on the TREND of population, so far we don’t estimated the population size and geographic range yet.

    BBS in Taiwan is a big citizen science cooperated with Endemic Species Research Institute of Council of Agriculture, Executive Yuan and Department of Ecology and Evolution of National Taiwan University. If anyone want to access the result of BBS in Taiwan, I can be the contact between BirdLife and BBS.

    Rusting Laughing Thrush is wild distributed but it’s quite rare in Taiwan. For example, RLT is only been found in 13 out of 311 plots in 2012 BBS. Comparing to Laughing Thrushes such as Taiwan Huamei (G. taewanus): 48 plots it’s quite rare.

  2. Andy Symes says:

    Preliminary proposals

    Based on available information, our preliminary proposal for the 2014 Red List is to pend the decision on Rusty Laughingthrush Garrulax poecilorhynchus and keep this discussion open until early 2015, while leaving the current Red List category unchanged in the 2014 update.

    There is now a period for further comments until the final deadline of 31 March, after which recommended categorisations will be put forward to IUCN.

    The final Red List categories will be published on the BirdLife and IUCN websites in mid-2014, following further checking of information relevant to the assessments by both BirdLife and IUCN.

  3. Andy Symes says:

    Recommended categorisation to be put forward to IUCN

    Following further review, there has been no change to our preliminary proposal for the 2014 Red List status of this species.

    This discussion will remain open for further comments and information until early 2015, and the current Red List category will remain unchanged in 2014.

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