Justification of Red List category
This species has a very small population and for this reason it is evaluated as Vulnerable under Criterion D.
Population justification
The population size is unknown, but has increased in recent years (P. Salaman in litt. 2007) from only 50-100 birds in 1995 (Howell and Webb) owing to habitat management and the culling of goats, however it is still thought likely to number fewer than 250 mature individuals.
Trend justification
Although the population was previously in decline (Howell and Webb 1995a), it has increased in recent years (P. Salaman in litt. 2007).
Junco insularis is endemic to Guadalupe Island, 280 km west of Baja California, Mexico, where it was once common and among the island's most abundant birds. It is now patchily distributed in the north of the island.
Mostly limited to Monterey pine–island oak (Pinus radiata–Quercus tomentella) and Guadalupe cypress (Cupressus guadalupensis) groves at north end of Guadalupe Island, at up to 1400 m, but can be found also in Nicotiana scrub at sea-level. In non-breeding season, occupies a variety of edge habitats and open woods with brushy understorey, and often visits feeders (Rising 2016),
The species has been threatened by extremely intense grazing by goats. The largest tract of remnant cypress forest on Guadalupe Island was c.3 km long in 1971, but only c.1 km by 1988. Smaller forest patches presumably experience similar intense grazing, leading to a total lack of regeneration. Feral cats were common in 1988 and presumably prey upon this species. Numbers have increased in recent years owing to habitat management and the culling of goats.
Conservation Actions Underway
Guadalupe is designated as a biosphere reserve (S. N. G. Howell in litt. 1998), but historically there has been little active management (Mirsky 1976. 5. Stattersfield et al. 1998). Nearly 35,000 goats were removed in 1970 and 1971, but in the late 1990s numbers were still estimated at 10,000 individuals (Stattersfield et al. 1998). There is apparently governmental interest in eradicating introduced predators and herbivores (B. Tershy and B. Keitt in litt. 1999), and non-governmental organisations in the region are developing the capacity to undertake eradication programmes on such large islands (B. Tershy and B. Keitt in litt. 1999).
Conservation Actions Proposed
Eradicate goats and cats from the island (B. Tershy and B. Keitt in litt. 1999). Survey to provide a more recent assessment of the population size and remaining habitat.
Text account compilers
Bird, J., Butchart, S., Ekstrom, J., Gilroy, J. & Wheatley, H.
Recommended citation
BirdLife International (2024) Species factsheet: Guadalupe Junco Junco insularis. Downloaded from
https://datazone.birdlife.org/species/factsheet/guadalupe-junco-junco-insularis on 23/11/2024.
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 23/11/2024.