Data Zone
Justification of Red List category
Although this species may have a restricted range, it is not believed to approach the thresholds for Vulnerable under the range size criterion (extent of occurrence < 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 appears to be decreasing, the decline is 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 is very large, and hence does not 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). For these reasons the species is evaluated as Least Concern.
Population justification
The species is described as uncommon or rare (Brinkhuizen and Nilsson 2020). The population on San Cristóbal has been estimated at 3,000-9,000 territories (Dvorak et al. 2019), which equates to 6,000-18,000 mature individuals. Even under the assumption that the population on the other inhabited islands occurs at a lower density, the global population is extrapolated at roughly 70,000-99,999 mature individuals.
Trend justification
The species is suspected to be in slow decline (J. Freile in litt. 2018). It has probably already disappeared from Floreana, with the last confirmed records of single individuals in 2008 (Dvorak et al. 2017, Fessl et al. 2017). Declines were likely driven by the loss and degradation of suitable habitat through anthropogenic impacts and the spread of non-native species (Dvorak et al. 2017).
Over the past ten years however, tree cover loss has been largely non-existent within the range (Global Forest Watch 2023). The impacts of habitat degradation and of introduced species have not been quantified. Even though a population decline is precautionarily suspected, the rate may be very low.
The species occurs in the Galápagos islands, Ecuador. It is found on the larger islands, being most numerous on San Cristóbal, Santa Cruz and Isabela (Brinkhuizen and Nilsson 2020, eBird 2023). It was formerly common on Floreana, but has not been observed since 2008, and it is unclear whether a population persists (Dvorak et al. 2017, Fessl et al. 2017).
It inhabits montane forests and dense woodland (Brinkhuizen and Nilsson 2020, Jaramillo 2020).
Potential threats to the species include the loss and fragmentation of its habitat for agricultural expansion and plantations (Dvorak et al. 2017, 2019). This threat however appears historical, as tree cover loss has been virtually absent since 2015 (Global Forest Watch 2023). Grazing by non-native animals like cattle, goats and donkeys is degrading suitable habitat, while introduced predators like cats, dogs and rats may pose an additional risk (Dvorak et al. 2017, 2019). Nestlings are moreover parasitised by Philornis downsi; however, despite high abundance of P. downsi, nestling mortality is relatively low (Heimpel et al. 2017).
Conservation Actions Underway
The species occurs within Galápagos National Park. Regular monitoring is carried out as part of the Landbird Conservation Programme.
Conservation Actions Proposed
Continue to regularly monitor the population trend. Restore degraded habitat. Consider eradicating non-native species, at least in parts of the range.
Text account compilers
Hermes, C.
Contributors
Butchart, S., Ekstrom, J. & Freile, J.
Recommended citation
BirdLife International (2024) Species factsheet: Vegetarian Finch Platyspiza crassirostris. Downloaded from
https://datazone.birdlife.org/species/factsheet/vegetarian-finch-platyspiza-crassirostris 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.