Data Zone
Justification of Red List category
This species occurs in two disjunct areas in Mexico; its population is small. It is locally threatened by habitat loss and degradation, thus its population is suspected to be declining slowly. For these reasons the species is listed as Near Threatened.
Population justification
Based on density estimates of 0.099-0.132 individuals/ha, the population in Veracruz was estimated at fewer than 2,500 indiviudals (Ortiz-Pulido et al. 2002). In Yucatán, no more than 6,000-10,000 individuals were estimated, assuming (optimistically) that the species occurs at a density three to four times higher than in Veracruz (R. Ortiz-Pulido in litt. 2012). This totals to 8,500-12,500 individuals, equating to 5,600-8,300 mature individuals and therefore, the population is here placed in the band 2,500-9,999 mature individuals.
Trend justification
Both populations are suspected to be in decline owing to habitat degradation. Between 1970 and 2017, the species declined moderately by 15-49% (Partners in Flight 2010). Assuming a constant and ongoing decline, this equates to a rate of 3-13% over ten years.
This species occurs in Mexico and has two disjunct populations: one in central Veracruz, and one on the northern fringe of the Yucatán peninsula. A recent review found no morphological differences between the two populations, but it has been reported that there are distinct ecological (Ortiz-Pulido et al. 2002) and some genetic differences (Licona-Vera and Ornelas 2014). The Veracruz population must be tiny, and declining (Ortiz-Pulido et al. 2002). The Yucatán population may also be declining due to habitat loss (R. Ortiz-Pulido in litt. 2016).
The Yucatán population is commonly found in a narrow (c.1 km wide) coastal strip (although the range is now known to extend at least 4 km inland [Santamaria-Rivero et al. 2013]), mainly in the ecotone between mangroves and tropical deciduous forest (Ortiz-Pulido et al. 2002), but also breeds in gardens and urban areas (S. Howell in litt. 2003; Santamaria-Rivero et al. 2013). The Veracruz population occurs in undisturbed, dry deciduous forest and overgrazed habitats c.25 km inland (Ortiz-Pulido et al. 2002; S. Howell in litt. 2003). The species has been observed feeding at flowers of Ipomoea, Malvaviscus, Agave, Justicia and Helicteres guazumaefolia in Veracruz (Ortiz-Pulido et al. 1998, 2002; Díaz-Valenzuela et al. 2011), and its diet is supplemented by small arthropods (del Hoyo et al. 1999). An unpublished study suggests that both populations feed on nectar from a similar range of plant species (R. Ortiz-Pulido in litt. 2016). In Veracruz, breeding condition has been noted in May, and a nest with small chicks was found in early August (Ortiz-Pulido et al. 1998; Howell 2002). In Yucatán, nesting takes place in August-April, with recently fledged young reported in February and March (Howell and Webb 1995; Ortiz-Pulido et al. 2002). Its nest, in which two eggs are laid, is cup-shaped, and made of seeds of Compositae, lichens and spiders' webs (Ortiz-Pulido et al. 1998, Peterson et al. 2016). Both populations apparently undergo a short-range, seasonal migration (Santamaria-Rivero et al. 2013; R. Ortiz-Pulido in litt. 2016).
The Veracruz and Yucatán populations are subject to different threats, both causing habitat degradation. The Veracruz population is threatened by severe habitat degradation as a result of livestock grazing, sugar cane cultivation and residential development (Ortiz-Pulido et al. 2002), while the Yucatan population is under pressure mainly from development of its coastal dune habitat for tourism (J. F. Ortega-Pimienta in litt. 2012; R. Ortiz-Pulido in litt. 2012, 2016).
Conservation Actions Underway
It occurs in three protected areas (Biosphere Reserves Ría Lagartos and Río Celestún, and Special Biosphere Reserve Bocas de Dzilám de Bravo). The species is included on the 'Watch List' of the State of North America's Birds as a species of high conservation concern (NABCI 2016).
Text account compilers
Hermes, C., Everest, J.
Contributors
Ashpole, J, Benstead, P., Howell, S., Ortega-Pimienta, J., Ortiz-Pulido, R., Sharpe, C.J., Symes, A. & Taylor, J.
Recommended citation
BirdLife International (2024) Species factsheet: Mexican Sheartail Doricha eliza. Downloaded from
https://datazone.birdlife.org/species/factsheet/mexican-sheartail-doricha-eliza on 24/12/2024.
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 24/12/2024.