Justification of Red List Category
After not having been observed for 40 years, this species has been rediscovered, with records from several new localities. It has a small population and a small known range, within which the quality of habitat is declining. Nevertheless, the species seems to be tolerant of some habitat degradation and there is no evidence of a population decline. Therefore, the species is listed as Near Threatened.
While the species has a small range, it is not uncommon in suitable habitat. Including the newly-recorded localities, the species's mapped range covers an area of 1,253 km2. Based on the recorded population densities of congeners, and assuming that 11-22% of the range is occupied, the species’s population size is estimated to fall within the band 2,800 – 8,400 individuals, roughly equivalent to 1,800 – 5,600 mature individuals. The national Red List of Colombia estimated the population size as 14,690 individuals (roughly equivalent to 9,800 mature individuals; Renjifo et al. 2014). Therefore, the population size is here placed in the band 1,800-9,999 mature individuals.
There is no data on population trends and no quantified information on rates of habitat loss. It is likely that there is a continuing decline in the extent and quality of habitat due to grazing and burning (Renjifo et al. 2014). However, it is unclear whether the population size is undergoing a continuing decline, and it has been suggested that the population might even be stable (P. Pulgarín and O. Cortes in litt. 2012).
Diglossa gloriosissima is local and apparently scarce in the West Andes of Colombia (Ridgely and Tudor 1989). Until recently, it was known from three well-spaced localities in the West Andes: Páramo Frontino and Cerro Paramillo, Antioquia, and Cerro Munchique, Cauca (Moynihan 1979, Ridgely and Tudor 1989, Fjeldså and Krabbe 1990). The species went unreported for 40 years after a record from the páramo at Frontino in 1965 (Moynihan 1979), but more recently there have been reports from various high peaks in the north of the West Andes (Carantón 2014), south to the Serranía del Pinche (Cortés-Diago et al. 2007, Carantón 2014). The first record came from near Jardin, Antioquia, in October 2003 (Pulgarín et al. 2005, Pulgarín and Munera 2006). It was followed by records made in August 2004 at the type locality (Flórez et al. 2004), and 70 km further south at Farallones del Citará (Pulgarín et al. 2005, P. C. Pulgarín in litt. 2006). At the latter site, three individuals were netted and three others were seen in the field during three days of fieldwork (Pulgarín and Munera 2006). At the type locality, ten individuals were observed and three collected during six days of fieldwork, and the species was described as locally common (Flórez et al. 2004). It has since also been recorded at Tatamá National Park near Cerro Montezuma, and at Reserva Mesenia-Paramillo near Mesenia (O. Cortes in litt. 2011). The small number of sightings probably reflects the dearth of fieldwork at these sites and on high mountains between them (Parker et al. 1996), with the exception of the relatively well-known Cerro Munchique, and likely reflects the lack of exploration and difficulties related to gaining access to the highlands of the Western Cordillera.
The species occurs near the timberline at elevations of 3,000-3,800 m in semi-humid/humid montane scrub and at the edge of elfin forest, apparently ranging only a few metres or tens of metres below the 'páramo' edge (Moynihan 1979, Ridgely and Tudor 1989, Fjeldså and Krabbe 1990, Parker et al. 1996). It favours Polylepis spp. with other small trees such as Escallonia or Baccharis. (O. Cortes in litt. 2011). Like most members of the genus, however, it does seem able to tolerate some habitat degradation and its population density is fairly high (Flórez et al. 2004). An apparent competitor is Black-throated Flowerpiercer Diglossa brunneiventris, with territories of the two species being mutually exclusive in the páramo at Frontino (Moynihan 1979).
Generally, the key threats to 'páramo' and elfin forest habitats are livestock-grazing and fires set by tourists or to encourage the vegetation to shoot (Wege and Long 1995, Kessler and Herzog 1998, P. G. W. Salaman in litt. 1999, Koenen and Koenen 2000). A study in Ecuador found Black Flowerpiercer Diglossa humeralis to be significantly more abundant in páramo that had been unburnt for eight years than in páramo burnt two months before counts (Koenen and Koenen 2000). It is not known whether Diglossa gloriosissima uses the animal-pollinated flowers of herbs and shrubs in less-disturbed páramo (and largely replaced by grasses in frequently burnt páramos [Koenen and Koenen 2000]), but if so, it is likely to be significantly affected by frequent fires. Human settlement and extensive deforestation threaten the species's habitat near Cerro Paramillo. A communication facility and associated military activity near the top of Cerro Munchique and its timberline may have a negative impact on the species (P. G. W. Salaman in litt. 1999). However, most areas where the species has recently been found are relatively inaccessible and are currently in protected (private or governmental) areas (P. Pulgarín in litt. 2012).
Conservation Actions Underway
Considered Vulnerable at the national level in Colombia (Renjifo et al. 2014). The species has been recorded in Paramillo and Munchique National Parks, Reserva Mesenia-Paramillo and Tatama National Park (P. G. W. Salaman in litt. 1999, O. Cortes in litt. 2011). It is also found in ProAves's Las Tangaras and Colibrí del Sol Natural Bird Reserves and Corantioquia's Cuchilla Jardín-Támesis, Farallones de Citará and Alto de San José-Cerro Plateado reserves (Carantón 2014).
Conservation Actions Proposed
Determine the population size and trends at the sites with recent records. Survey the high peaks of the West Andes to determine the true extent of the range and overall population size of this species. Support, finance and enforce better conservation measures for the two national parks. Manage protected páramos by increasing the amount of time between fires (Koenen and Koenen 2000). Extend Las Orquídeas National Park into the páramo zone (Flórez et al. 2004).
14.5 cm. Smart, chestnut-and-black flowerpiercer. Black with blue shoulder patch and rufous-chestnut lower breast and belly. Similar spp. Black-throated Flowerpiercer D. brunneiventris is more extensively rufous below, with black limited to small throat patch, and greyish flanks and shoulder. Voice A house sparrow-like but higher pitched chirrup, and complex, high-pitched vocalisations similar to those of other flowerpiercers.
Text account compilers
Sharpe, C.J., Wheatley, H., Stuart, T., Symes, A., Capper, D., Butchart, S., Hermes, C., Temple, H., Pople, R.
Cortés, O., Pulgarín, P.C. & Salaman, P.G.W.
BirdLife International (2022) Species factsheet: Diglossa gloriosissima. Downloaded from http://www.birdlife.org on 09/08/2022. Recommended citation for factsheets for more than one species: BirdLife International (2022) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 09/08/2022.