email a friend
printable version
Bell's Vireo Vireo bellii
BirdLife is updating this factsheet for the 2016 Red List
Please email us with any relevant information

This species has undergone moderately rapid declines and hence is considered to be Near Threatened.

Taxonomic source(s)
AOU. 1998. Check-list of North American birds. American Ornithologists' Union, Washington, D.C.
Sibley, C. G.; Monroe, B. L. 1990. Distribution and taxonomy of birds of the world. Yale University Press, New Haven, USA.
Stotz, D. F.; Fitzpatrick, J. W.; Parker, T. A.; Moskovits, D. K. 1996. Neotropical birds: ecology and conservation. University of Chicago Press, Chicago.

Distribution and population
Vireo bellii summers in central and south-western USA and northern Mexico. Its winter range extends from south Baja California along the west coast of Central America, through Mexico, El Salvador, Guatemala, Nicaragua and Honduras (Brown 1993). The species has shown a decline of 2.7% per year since 1966 (J. Wells and K. Rosenberg in litt. 2003).

Population justification
Rich et al. (2004).

Trend justification
This species has undergone a large and statistically significant decrease over the last 40 years in North America (-66.1% decline over 40 years, equating to a -23.7% decline per decade; data from Breeding Bird Survey and/or Christmas Bird Count: Butcher and Niven 2007).

It frequents dense, low, shrubby vegetation in its breeding range where it has been extensively studied (Brown 1993). However, very little is known about its density, ecology or habitat use in the winter grounds.

Habitat loss and modifications through agricultural spread, logging and housing developments have caused declines and continue to threaten the species. Secondarily, rates of brood parasitism by Brown-headed Cowbirds (Molothrus ater), have caused reductions in breeding populations in south-west USA (Brown 1993).

Conservation Actions Underway
Trapping cowbirds can significantly reduce brood parasitism (Collins et al. 1991), and is a standard management tool in one California study area (Beezley and Rieger 1987). Conservation Actions Proposed
Protect key habitats for the species and manage others in a beneficial way. Continue to monitor trends and ascertain whether it is still declining. Identify the key threats and develop appropriate actions to tackle them.

Beezley, J. A.; Rieger, J. P. 1987. Least Bell's Vireo management by cowbird trapping. Western Birds 18: 55-61.

Brown, B. T. 1993. Bell's Vireo Vireo bellii. In: Poole, A.; Gill, F. (ed.), The birds of North America, No. 35, pp. 1-20. The Academy of Natural Sciences, Philadelphia and the American Ornithologists' Union, Philadelphia and Washington, DC.

Collins, C. T.; Corey, K.; Pike, J.; Hays, L. R. 1991. The status and management of the Least Bell's Vireo within the Prado Basin, California, 1986-1990.

Rich, T.D.; Beardmore, C.J.; Berlanga, H.; Blancher, P.J.; Bradstreet, M.S.W.; Butcher, G.S.; Demarest, D.W.; Dunn, E.H.; Hunter, W.C.; Inigo-Elias, E.E.; Martell, A.M.; Panjabi, A.O.; Pashley, D.N.; Rosenberg, K.V.; Rustay, C.M.; Wendt, J.S.; Will, T.C.

Further web sources of information
Explore HBW Alive for further information on this species

Search for photos and videos, and hear sounds of this species from the Internet Bird Collection

Text account compilers
Benstead, P., Bird, J., Harding, M., Sharpe, C J

Butcher, G., Rosenberg, K., Wells, J.

IUCN Red List evaluators
Butchart, S., Symes, A.

Recommended citation
BirdLife International (2016) Species factsheet: Vireo bellii. Downloaded from on 26/10/2016. Recommended citation for factsheets for more than one species: BirdLife International (2016) IUCN Red List for birds. Downloaded from on 26/10/2016.

This information is based upon, and updates, the information published in BirdLife International (2000) Threatened birds of the world. Barcelona and Cambridge, UK: Lynx Edicions and BirdLife International, BirdLife International (2004) Threatened birds of the world 2004 CD-ROM and BirdLife International (2008) Threatened birds of the world 2008 CD-ROM. These sources provide the information for species accounts for the birds on the IUCN Red List.

To provide new information to update this factsheet or to correct any errors, please email BirdLife

To contribute to discussions on the evaluation of the IUCN Red List status of Globally Threatened Birds, please visit BirdLife's Globally Threatened Bird Forums.

Additional resources for this species

ARKive species - Bell's vireo (Vireo bellii) 0

Key facts
Current IUCN Red List category Near Threatened
Family Vireonidae (Vireos and allies)
Species name author Audubon, 1844
Population size mature individuals
Population trend Decreasing
Distribution size (breeding/resident) 291,000 km2
Country endemic? No
Links to further information
- Additional Information on this species