Chestnut-bellied Flowerpiercer (Diglossa gloriosissima): request for information

BirdLife species factsheet for Chestnut-bellied Flowerpiercer

Chestnut-bellied Flowerpiercer (Diglossa gloriosissima) is local and apparently scarce in the West Andes of Colombia (Ridgely and Tudor 1989), where it occurs near the timberline at high altitude in semi-humid/humid montane scrub and elfin forest edge (Moynihan 1979, Ridgely and Tudor 1989, Fjeldså and Krabbe 1990).

Until recently it was known from three well-spaced localities in the West Andes of Colombia: Páramo Frontino and Cerro Paramillo, both in Antioquia, and Cerro Munchique, in 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 (Caranton 2014), south to the Serranía del Pinche (Cortes-Diago et al. 2007, Caranton 2014).

The species is currently listed as Endangered under Criterion B1, but following revision of the species’s range map to include newly-recorded localities, and with implementation of the recommended method of calculating the Extent of Occurrence (EOO) using a minimum convex polygon, the species no longer qualifies as Endangered under this criterion. Hence, we are undertaking a review of the species’s Red List Category.

Our current information on the species’s conservation status will now be compared to all Red List Criteria.

Criterion A – We have no data on population trends and no quantified information on rates of habitat loss. The species cannot be assessed under this criterion.

Criterion B – Following revision of its range map,the species’s extent of occurrence (EOO) is estimated at c.25,200 km2.  This does not meet the threshold for listing the species as threatened under Criterion B1. It could potentially qualify for listing as Near Threatened or Least Concern under Criterion B1. The species’s area of occupancy (AOO) has not been quantified, but based on a 4 km2 grid placed over the area of mapped range, must be smaller than 1,792 km2. This meets the threshold for Vulnerable under Criterion B2. To list the species as threatened on the Red List under Criterion B, two of conditions a-c must also be met.

The species is not severely fragmented according to the IUCN definition, since the majority of the population is not found in habitat patches that are smaller than would be required to support a viable population, and separated from other habitat patches by a large distance. The main threat to the species is considered to be habitat loss primarily due to livestock grazing (Caranton 2014). Since habitat loss is occurring at a slow rate, the number of locations (according to the IUCN definition) is likely to be significantly greater than 10. Therefore, condition a is not met.

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). Condition b is met.

There is no evidence that the species’s population or range size are undergoing extreme fluctuations. Condition c is not met.

The species’s AOO falls beneath the threshold for listing the species as Vulnerable and there is likely to be a continuing decline in the area and extent of the species’s habitat, which meets condition a. However, based on current evidence the species is not severely fragmented, it has more than ten locations and it is not experiencing extreme fluctuations, so neither conditions a or c are met. The species could qualify for Near Threatened or Least Concern under this criterion.

Criterion C – The species’s population size has previously been estimated at 1,000-2,499 mature individuals. Based on the area of the species’s mapped range (1,253 km2), 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 range 2,800 – 8,400 individuals, roughly equivalent to 1,800 – 5,600 mature individuals. The Colombian national Red List estimated the population size as 14,690 individuals (roughly equivalent to 9,800 mature individuals; Renjifo et al. 2014). This range of figures could qualify the species for listing as Endangered or Vulnerable under Criterion C.To list the species as threatened on the Red List under Criterion C further conditions must also be met.

The species’s habitat quality and extent is considered to be declining (Renjifo et al. 2014). However, it is unclear whether the population size is undergoing a continuing decline. We do not have population data from which to estimate the rate of decline, so the species cannot be assessed under Criterion C1.

The species has multiple subpopulations and based on the minimum estimated population size, it is possible that the largest subpopulation numbers no more than 1,000 mature individuals, meaning that the species meets condition 2a(i) at the level of Vulnerable. Less than 90% of individuals are found in any one subpopulation, meaning that the species does not meet condition 2a(ii). There is no evidence that the species’s population size is undergoing extreme fluctuations so the species doesn’t meet condition b.

The species’s population size may fall beneath the threshold for listing the species as Endangered or Vulnerable under Criterion C, and condition 2a(i) is met at the level of Vulnerable, but it is unclear whether the species is undergoing a continuing to decline. If a continuing decline can be inferred, for example, from information on habitat loss or degradation, then the species could qualify as Vulnerable under Criterion C. If not, the species should be listed as Near Threatened under this Criterion.

Criterion D – Based on the population estimates described above, the species’s population size does not meet or approach the threshold for Vulnerable under Criterion D. The species does not have a restricted area of occupancy of number of locations such that deforestation could drive the species to Critically Endangered or Extinct within a very short time. The species does not therefore meet the criteria for listing as Vulnerable under Criterion D2. The species is therefore assessed as Least Concern under Criterion D.

Criterion E – To the best of our knowledge no quantitative assessment of the probability of extinction has been conducted for this species, and so it cannot be assessed against this criterion.

To allow us to achieve a clearer assessment of the species’s status, information is requested on the species’s conservation status. We particularly request information on its population size and trends, threats and trends in the extent and quality of its habitat.

Please note that this topic is not designed to be a general discussion about the ecology of the species, rather a discussion of the species’s Red List status. Therefore, please make sure your comments are about the proposed listing.

An information booklet on the Red List Categories and Criteria can be downloaded here and the Red List Criteria Summary Sheet can be downloaded here. Detailed guidance on IUCN Red List terms and definitions and the application of the Red List Categories and Criteria can be downloaded here.

References

Caranton, D. A. (2014) Diglossa gloriosissima. In: Renjifo, L. M., Franco-Maya, A. M., Amaya-Espinel, J. D. Kattan, G. H., and López-Lanús, B. (2002) Libro rojo de aves de Colombia. Instituto de Investigación de Recursos Biológicos Alexander von Humboldt y Ministerio del Medio Ambiente, Bogotá, Colombia.

Cortés-Diago, A., Ortega, L. A., Mazariegos-Hurtado, L., & Weller, A. A. (2007) A new species of Eriocnemis (Trochilidae) from southwest Colombia. Ornitología Neotropical 18(2): 161-170.

Fjeldså, J. and Krabbe, N. 1990. Birds of the high Andes. Apollo Books, Copenhagen.

Moynihan, M. (1979) Geographic variation in social behaviour and in adaptations to competition among Andean birds. Publications of the Nuttall Ornithological Club 18: 1-162.

Renjifo, L. M., Franco-Maya, A. M., Amaya-Espinel, J. D. Kattan, G. H., and López-Lanús, B. (2002) Libro rojo de aves de Colombia. Instituto de Investigación de Recursos Biológicos Alexander von Humboldt y Ministerio del Medio Ambiente, Bogotá, Colombia.

Ridgely, R. S. and Tudor, G. (1989) The birds of South America. University of Texas Press, Austin, Texas.

This entry was posted in Americas, South America and tagged , . Bookmark the permalink.

2 Responses to Chestnut-bellied Flowerpiercer (Diglossa gloriosissima): request for information

  1. Red List Team (BirdLife International) says:

    Preliminary proposal
    Based on available information, our proposal for the 2019 Red List is to pend the decision on this species and keep the discussion open until 2020, while leaving the current Red List category unchanged in the 2019 update.
    Final 2019 Red List categories will be published on the BirdLife and IUCN websites in December, following further checking of information relevant to the assessments by both BirdLife and IUCN.

  2. Hannah Wheatley (BirdLife) says:

    Recommended categorisation to be put forward to IUCN

    Following further review, our proposal for the 2019 Red List for this species has been changed.

    Chestnut-bellied Flowerpiercer (Diglossa gloriosissima) is now recommended to be listed as Near Threatened, approaching the thresholds for listing as threatened under Criteria B1ab(iii)+2ab(iii); C2a(i).

    The final 2019 Red List categories will be published on the BirdLife and IUCN websites in December, following further checking of information relevant to the assessments by both BirdLife and IUCN.

Comments are closed.