Justification of Red List category
Gallicolumba luzonica is listed as Near Threatened under Criteria C1. There is high uncertainty in the species' population size, though the overall population is very likely below 10,000 individuals. The species is suspected to be undergoing continuing declines in the population due to continued degradation of its habitat, forest loss, hunting and trade, and the potential local extinction of several small populations. However, current evidence means continuing declines are only suspected.
Population justification
There is little information about the population size of Gallicolumba luzonica. However, it is considered rare or scarce across its range, though the species may be underreported due to its shy nature (Gibbs et al. 2001, Baptista et al. 2020). The species occurs in undoubtedly low numbers on Polilo where it suffers from continued hunting pressure (Gonzalez and Dans 1996, Gibbs et al. 2001), and Catanduanes where it is known from only a single observation (BirdLife International 2001, Gibbs et al. 2001).
Bird surveys were undertaken December 2009 to September 2010 covering 14 sites across Central Luzon, the Cordillera, Sierra Madre, South Luzon, and West Luzon (Española et al. 2013), covering much of the known range of G. luzonica. The species was found in the highest densities in Cordillera and Central Luzon, and in lower densities in Sierra Madre, South Luzon, and West Luzon, with the species being absent from only the Malinao region in South Luzon (Española et al. 2013). This study estimated site-specific species densities using distance sampling software (Thomas et al. 2010; see Española et al. [2013] for full methods), and used these to derive population estimates for five protected areas (Española et al. 2013). From this method, a G. luzonica population for Northern Sierra Madre National Park (NSMNP) of 4,260 (1,554-15,713) individuals was provided (Española et al. 2013). The second largest population estimate was for Balbalasang-Balbalan National Park, comprising 1,430 (574-3,559) individuals (Española et al. 2013). The remaining protected areas of Quezon Protected Landscape, Mount Isarog Natural Park, and Subic Bay Forest Reserve and Bataan Natural Park had estimated populations of less than 250 individuals each (Española et al. 2013).
The population estimates provided by these surveys have wide confidence intervals (i.e., NSMNP), and represent population sizes for only a select few protected areas (Española et al. 2013). Additionally, the species does occasionally occur in selectively logged and poor-quality secondary growth, including plantations (BirdLife International 2001). However, it is a forest-dependent ground foraging species, and does not venture onto wider paths or clearings (Gibbs et al. 2001). Therefore, although it may occur in less preferable habitat, it is expected that its population density and range is much restricted by large expanses of degraded and unsuitable habitat (Gibbs et al. 2001). The population densities estimated for protected areas (Española et al. 2013) are therefore expected to represent the highest densities of the species. Combining the minimum and maximum population estimates from Española et al. (2013) gives a total population across the five protected areas of c. 2,000-20,000 individuals. Accounting for the unsampled parts of the species' range, and considering that it likely occurs in much lower densities outside protected areas, a total population of 5,000-25,000 mature individuals is estimated.
Trend justification
Within the current range of G. luzonica, there has been c. 4% forest loss over the past three-generations, and a maximum of c. 8% projected over the next three-generations (Global Forest Watch 2024, based on data from Hansen et al. [2013] and methods disclosed therein). However, forest loss data likely underestimates the rate of decline for the species. G. luzonica shows partial tolerance for degraded habitats (BirdLife International 2001), but is largely a forest dependent species, that does not venture into clearings (Gibbs et al. 2001). A large portion of the population occurs in Northern Sierra Madre National Park (Española et al. 2013), which is being continually degraded from illegal logging and subsistence timber harvesting at the edges (van der Ploeg 2011). Indeed, habitat degradation is apparent in all areas where the species occurs (Global Forest Watch 2024 based on data from Grantham et al. [2020]). Furthermore, the species it at risk of becoming locally extinct in several areas where it has a small, estimated population, including Mount Isarog Natural Park (c. 234 individuals), Subic Bay Forest Reserve and Batann Natural Park combined (c. 193 individuals) (previously logged), and Quezon Protected Landscape (c. 55 individuals; Española et al. 2013). Declines in the population are likely to be further exacerbated by hunting for consumption (Scheffers et al. 2012), and for the pet trade (BirdLife International 2001, Baptista et al. 2020, Donald et al. 2024). Past declines in the population are likely more in the range of 5-20% when considering continuing loss of habitat quality, and additional impacts of hunting. Further declines are expected in the future, considering the potential for local extinctions in several of the smaller reserves and the ongoing degradation in Sierra Madre and Cordillera (Española et al. 2013, Global Forest Watch 2024).
Gallicolumba luzonica is endemic to Luzon, Polilo and Catanduanes Islands Philippines (Gibbs et al. 2001, Allen 2020). The species occurs from North Luzon, through to South Luzon as far as Bulusan (eBird 2024). However, the species is considered rare or scarce across its range, and its distribution is likely to be patchy and largely confined to protected areas (Gibbs et al. 2001, Baptista et al. 2020). The species' current status on Catanduanes is uncertain, as it is known from only a single observation in the 1980s (BirdLife International 2001, Gibbs et al. 2001).
G. luzonica occurs in primary and secondary forest, primarily a lowland species but found up to 1,400 m in all forest types (Poulsen 1995, Gibbs et al. 2001, Baptista et al. 2020). The species is occasionally found in selectively logged forest, poor-quality regrowth, and plantations (BirdLife International 2001, Gibbs et al. 2001) but is a ground-foraging species, and does not venture onto wider paths or into clearings (Gibbs et al. 2001). The species is usually seen feeding on the ground on seeds, berries, insects, worms, and other invertebrates, or when flushed where it will fly a short distance before dropping into cover (Gibbs et al. 2001, Baptista et al. 2020).
G. luzonica is primarily threatened by habitat loss, and the fragmentation and isolation of its populations, as well as hunting and trade of the species. The Philippines went from 68% to 23% total land cover by forests between 1876 and 2003 (Fernando 2005). There is now less than 1 million ha of primary forest left, caused by a mix of logging activities, shifting cultivations, permanent agriculture and mining (Lasco et al. 2001, Apan et al. 2017). This species is forest-dependent and does not venture onto wider paths or into clearings (Gibbs et al. 2001). Furthermore, it is a ground-dwelling species that is reluctant to fly (Gibbs et al. 2001), suggesting that the loss of suitable habitat may lead to increased fragmentation and isolation of its population due to likely short dispersal distances. There are less than 250 individuals estimated to occur in each of several of the smaller reserves across Luzon (Española et al. 2013), which will be at high risk of further degradation, and consequentially the disappearance of the species from these areas in the future (Liu et al. 1993, Española et al. 2013). The species also occurs in very low numbers on Polilo and Catanduanes (Gonzalez and Dans 1996, BirdLife International, Gibbs et al. 2001), and is at high risk of becoming extinct on these islands in the future. The regions of Cordillera and Sierra Madre where the species occurs at higher abundances (Española et al. 2013) also suffer from declines in habitat quality. Illegal logging is rampant in Northern Sierra Madre National Park with subsistence timber harvesting occurring at the forest edges, gradually degrading the habitat quality (van der Ploeg 2011). The continued degradation and fragmentation of these areas from roads and logging is apparent (Global Forest Watch 2024 based on data from Grantham et al. [2020]). The Cordillera may be particularly at risk, with the diminutive Balbalasang-Balbalan National Park (14.43km2) the only current National Park in the region (UNEP-WCMC and IUCN 2024). Additionally, the species is under threat from hunting across its range, being commonly trapped by locals for meat and the pet trade (BirdLife International 2001, Baptista et al. 2020). Hunting occurs in several Protected Areas where the species occurs (Española et al. 2013). On Polilo Island, hunting is expected to cause the local extinction of the species in the near-future (Gonzalez and Dans 1996, Gibbs et al. 2001).
Conservation Actions Underway
Listed in CITES Appendix II.
28–30 cm; 133–184 g. All bleeding-hearts are remarkable for their breast markings, which appear like a deep, still-bleeding wound, an illusion most perfect in G. luzonica. A plump, short-tailed and long-legged bird. Forehead and wing-coverts light blue-grey, latter marked with three dark reddish brown bands across closed wing; crown, nape, sides of breast, mantle, back and rump dark grey with broad iridescent fringes giving overall appearance of violet-purple or bronzy green, depending on light; primaries, secondaries and central tail feathers dull dark brown; underwing chestnut; outer tail feathers blue-grey with blackish subterminal bands; throat, breast and underparts white, tinged pale pink below breast patch and more deeply pinkish-red adjacent to it, giving appearance of blood fading as it spread; longitudinal patch of blood-red feathers with loose, hairy texture in centre of breast; these feathers usually form a groove or indentation, enhancing the wound illusion; iris blue; orbital skin grey; bill blackish, grey at base; legs and feet red. Sexes alike, but female has iris purple or greyish purple. Juvenile presumably resembles that of G. crinigera. Races differ slightly, mainly in coloration of underparts: griseolateralis has darker forehead and crown than nominate, less clearly differentiated from purplish nape, with darker grey wing-coverts, and female has darker flanks and undertail-coverts and lower breast and abdomen whiter; rubiventris has darker red and more extensive breast patch, pale pinkish-brown belly washed pink, and pale brown undertail-coverts; also smaller. Sounds: Advertising call a repeated single mournful coo lasting c. 1·2 seconds, which reaches its highest frequency in the middle: “cooOOooh...... cooOOooh.....”. In display, reportedly utters a more rapidly delivered gruff “croo-cu-cu-cu-cu” or a soft “co-co-coooo”.
Text account compilers
Richardson, L.
Contributors
Michael, G., Webster, R., Benstead, P., Taylor, J. & Mahood, S.
Recommended citation
BirdLife International (2024) Species factsheet: Luzon Bleeding-heart Gallicolumba luzonica. Downloaded from
https://datazone.birdlife.org/species/factsheet/luzon-bleeding-heart-gallicolumba-luzonica on 20/12/2024.
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 20/12/2024.