VU
Visayan Wattled Broadbill Sarcophanops samarensis



Taxonomy

Taxonomic note
Sarcophanops samarensis (del Hoyo and Collar 2016) was previously listed as Eurylaimus samarensis.

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.
Lambert, F.; Woodcock, M. 1996. Pittas, broadbills and asities. Pica Press, Robertsbridge, U.K.

IUCN Red List criteria met and history
Red List criteria met
Critically Endangered Endangered Vulnerable
- - A2c+3c+4c

Red List history
Year Category Criteria
2024 Vulnerable A2c+3c+4c
2016 Vulnerable A2c+3c+4c
2012 Vulnerable A2c+3c+4c
2008 Vulnerable A2c; A3c; A4c
2006 Vulnerable
2004 Vulnerable
2000 Vulnerable
1994 Not Recognised
1988 Not Recognised
Species attributes

Migratory status not a migrant Forest dependency high
Land-mass type shelf island
Average mass 27 g
Range

Estimate Data quality
Extent of Occurrence (breeding/resident) 49,900 km2 medium
Number of locations 11-50 -
Severely fragmented? yes -
Population
Estimate Data quality Derivation Year of estimate
Population size 2500-9999 mature individuals poor suspected 2024
Population trend decreasing poor inferred 2017-2028
Rate of change over the past 10 years/3 generations (longer of the two periods) 15-35,25-35% - - -
Rate of change over the future 10 years/3 generations (longer of the two periods) 15-35,25-35% - - -
Rate of change over the past & future 10 years/3 generations (longer of the two periods) 15-35,25-35% - - -
Generation length 3.66 years - - -
Number of subpopulations 3-20 - - -
Percentage of mature individuals in largest subpopulation 1-89% - - -

Population justification: At one time evidently common given the number of historically collected specimens (BirdLife International 2001) but even by the mid-20th century, Rand and Rabor (1960) reported it to be rare on Samar and 'very rare' on Bohol. Brooks et al. (1995), however, considered it scarce on Bohol and commented that the species was 'unobtrusive and certainly under-recorded'. Allen (2020) considered it 'scarce' throughout its range, and a crude interpretation of citizen science data (eBird 2024) finds the species to be scarce, but also regularly recorded where it is found. Similarly, it was recorded at all eight watershed sites surveyed on Samar in 2002-2003 (Gruezo and Gonzalez 2014), although some of these have since been nearly totally denuded of suitable forest. It was notably not recorded in surveys of limestone forests in eastern Samar (Obeña et al. 2021). The population size of this species has not robustly been estimated, but BirdLife International (2001) considered it likely to be below 10,000 mature individuals (inferred from its listing under Criterion C1). The species appears to be confined to lowland forest and apparently tolerates little disturbance (BirdLife International 2001), although Allen (2020) did report it from 'well-developed secondary forest'. Within its geographic and elevational range there remains c. 5,000 km2 of suitable habitat, but only a proportion of this is likely to be occupied, since this estimate makes no consideration for forest integrity; habitat is also mostly distributed on Samar, where the species appears to be very scarce (Taylor et al. 2015, eBird 2024), despite increased observer effort in recent years. The population size is precautionarily suspected to number 2,500-9,999, following BirdLife International (2001) but surveys to confirm the species abundance, particularly on Samar/Leyte, are urgently needed.

Trend justification: No trend data are available for this species to robustly determine rates of decline, and so rates of forest cover loss is used as a proxy. Within its range, forest cover reduced by c.10–15% in the three generations (11 years) to 2023 (range determined using various assumptions regarding population abundance at different altitudes) (Global Forest Watch 2024, based on data from Hansen et al. [2013] and methods therein). While population trends in this highly forest-dependent species are thought to be closely tied to rates of forest cover loss, there are several reasons that these data in isolation may be (perhaps severely) underestimating rates of population decline. First, they make no attempt for forest degradation and modification, especially selective logging, which is thought to be rampant within this species' range (Apan et al. 2017, Grantham et al. 2020, Hutchinson 2021) as well as fragmentation. Second, the forest cover layers used by Global Forest Watch (2024) appear to overestimate the extent of suitable forest cover (in some instances evidently conflating highly degraded landscapes including plantations and parkland with forest), with rates of forest cover loss evidently skewed to areas of true natural forest likely to host this species. Thus on Samar/Leyte, where a majority of the species' population is thought to lie, the fastest rates of forest cover loss are occurring in and around Samar Island Natural Park (SINP), the only part of the island from which there are recent records (Taylor et al. 2015, eBird 2024). Accordingly, the rate of population reduction may be significantly more rapid than remote sensed land cover data suggest. Over the past three generations therefore, rates of population reduction are suspected to have fallen somewhere in the range of 15-35%, with a best and precautionary estimate of 25-35%. Future rates of reduction are harder to predict, but recent (2018-2023) rates of forest cover loss were consistent with the years before, such that a projection over the next three generations (11 years: 2024-2035) is thought to fall within the same range.


Country/territory distribution
Country/Territory Presence Origin Resident Breeding visitor Non-breeding visitor Passage migrant
Philippines extant native yes

Important Bird and Biodiversity Areas (IBA)
Country/Territory IBA Name
Philippines Anonang-Lobi Range
Philippines Mount Cabalantian - Mount Capoto-an complex
Philippines Mount Nacolod
Philippines Mount Yacgun - Mount Sohoton complex
Philippines Rajah Sikatuna Protected Landscape
Philippines Southern Samar mountains

Habitats & altitude
Habitat (level 1) Habitat (level 2) Importance Occurrence
Forest Subtropical/Tropical Moist Lowland major resident
Altitude 0 - 500 m Occasional altitudinal limits (max) 750 m

Threats & impact
Threat (level 1) Threat (level 2) Impact and Stresses
Agriculture & aquaculture Annual & perennial non-timber crops - Agro-industry farming Timing Scope Severity Impact
Ongoing Minority (<50%) Slow, Significant Declines Low Impact: 5
Stresses
Ecosystem degradation, Ecosystem conversion
Agriculture & aquaculture Annual & perennial non-timber crops - Shifting agriculture Timing Scope Severity Impact
Ongoing Minority (<50%) Slow, Significant Declines Low Impact: 5
Stresses
Ecosystem degradation, Ecosystem conversion
Agriculture & aquaculture Annual & perennial non-timber crops - Small-holder farming Timing Scope Severity Impact
Ongoing Minority (<50%) Slow, Significant Declines Low Impact: 5
Stresses
Ecosystem degradation, Ecosystem conversion
Agriculture & aquaculture Wood & pulp plantations - Agro-industry plantations Timing Scope Severity Impact
Ongoing Minority (<50%) Rapid Declines Medium Impact: 6
Stresses
Ecosystem degradation, Ecosystem conversion
Agriculture & aquaculture Wood & pulp plantations - Small-holder plantations Timing Scope Severity Impact
Ongoing Minority (<50%) Slow, Significant Declines Low Impact: 5
Stresses
Ecosystem degradation, Ecosystem conversion
Biological resource use Logging & wood harvesting - Unintentional effects: (large scale) [harvest] Timing Scope Severity Impact
Ongoing Minority (<50%) Slow, Significant Declines Low Impact: 5
Stresses
Ecosystem degradation, Ecosystem conversion
Biological resource use Logging & wood harvesting - Unintentional effects: (subsistence/small scale) [harvest] Timing Scope Severity Impact
Ongoing Minority (<50%) Slow, Significant Declines Low Impact: 5
Stresses
Ecosystem degradation, Ecosystem conversion
Energy production & mining Mining & quarrying Timing Scope Severity Impact
Ongoing Minority (<50%) Slow, Significant Declines Low Impact: 5
Stresses
Ecosystem degradation, Ecosystem conversion

Recommended citation
BirdLife International (2024) Species factsheet: Visayan Wattled Broadbill Sarcophanops samarensis. Downloaded from https://datazone.birdlife.org/species/factsheet/visayan-wattled-broadbill-sarcophanops-samarensis on 23/12/2024.
Recommended citation for factsheets for more than one species: BirdLife International (2024) IUCN Red List for birds. Downloaded from https://datazone.birdlife.org/species/search on 23/12/2024.