Vermivora crissalis 


Taxonomy [top]

Kingdom Phylum Class Order Family
Animalia Chordata Aves Passeriformes Parulidae

Scientific Name: Vermivora crissalis
Species Authority: (Salvin & Godman, 1889)
Common Name(s):
English Colima Warbler
Identification information:

Assessment Information [top]

Red List Category & Criteria: Least Concern ver 3.1
Year Published: 2012
Date Assessed: 2012-05-01
Assessor(s): BirdLife International
Reviewer(s): Taylor, J. & Butchart, S.
Contributor(s): Valdes, R.
Facilitator/Compiler(s): Isherwood, I., Mahood, S., O'Brien, A., Symes, A.
This species has been downlisted to Least Concern because it is no longer thought to be undergoing moderately rapid population declines, and is not thought to approach the thresholds for classification as Vulnerable under any other criteria. Nevertheless, the total population is thought to be moderately small and habitat loss remains a threat, and indications that the population is smaller than currently suspected, or undergoing rapid declines, would warrant reconsideration of its threat status.

Previously published Red List assessments:
2008 Near Threatened (NT)
2004 Near Threatened (NT)
2000 Lower Risk/near threatened (LR/nt)
1994 Lower Risk/near threatened (LR/nt)
1988 Near Threatened (NT)

Geographic Range [top]

Range Description: Vermivora crissalis is a fairly common but local breeder, occurring from Coahuila to north-east Zacatecas and northern San Luis Potosí, Mexico, and extreme south-west Texas, USA (Curson et al. 1994, Howell and Webb 1995a). It winters in west Mexico from south Sinaloa south to Guerrero and Morelos (Howell and Webb 1995a).

Countries occurrence:
Mexico; United States
Continuing decline in area of occupancy (AOO): Unknown
Extreme fluctuations in area of occupancy (AOO): No
Estimated extent of occurrence (EOO) - km2: 76800
Continuing decline in extent of occurrence (EOO): Unknown
Extreme fluctuations in extent of occurrence (EOO): No
Continuing decline in number of locations: Unknown
Extreme fluctuations in the number of locations: No
Lower elevation limit (metres): 1500
Upper elevation limit (metres): 3000
Range Map: Click here to open the map viewer and explore range.

Population [top]

Population: Rich et al (2003)

Trend Justification:  This species is suspected to be in slow to moderate decline owing to habitat degradation.
Current Population Trend: Decreasing
Additional data:
Continuing decline of mature individuals: Unknown
Extreme fluctuations: No Population severely fragmented: No
Continuing decline in subpopulations: Unknown
Extreme fluctuations in subpopulations: No All individuals in one subpopulation: No

Habitat and Ecology [top]

Habitat and Ecology: It breeds in pine-oak, oak and pinyon-juniper woodland, between 1,500 and 3,000 m (Curson et al. 1994, Howell and Webb 1995a), and is commonest in pine-oak woodland with a ground cover of bunchgrass (Wauer 1994). It winters in brushy understorey of humid to semi-humid montane forest from 1,500 to 3,500 m (Howell and Webb 1995a). The nest is usually on the ground, and eggs have been found in May (Curson et al. 1994).

Systems: Terrestrial
Continuing decline in area, extent and/or quality of habitat: Unknown
Generation Length (years): 3.8
Movement patterns: Full Migrant

Threats [top]

Major Threat(s): Grazing by goats, sheep and other exotic herbivores, increases in the populations of feral cats and dogs, and nest parasitism by Brown-headed Cowbirds Molothrus ater are potentially severe threats to populations of this warbler in Mexico (Wauer 1994).

Conservation Actions [top]

Conservation Actions: Conservation Actions Underway
None are known.

Conservation Actions Proposed
Regularly monitor the population at selected sites across its range to determine trends. Research the effects of grazing and wood cutting on populations of the species. Examine the effects of Brown-headed Cowbird parasitism at the population level. Protect significant areas of forest, in both strictly protected areas and community led multiple use areas.

Citation: BirdLife International. 2012. Vermivora crissalis. The IUCN Red List of Threatened Species 2012: e.T22721633A39865504. . Downloaded on 28 November 2015.
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