This discussion was first published as part of the 2013 Red List update, but remains open for comment to enable reassessment in 2015.
Flammulated Flycatcher Deltarhynchus flammulatus is restricted to the Mexican Pacific Region. It is currently listed as Least Concern as it was not thought to approach the thresholds for Vulnerable under any of the IUCN Red List criteria.
This species has a very large range, and hence does not 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). The population was estimated by Partners in Flight to number fewer than 50,000 individuals (Panjabi in litt. 2008), thus placed in the band 20,000-49,999 individuals, but it is not believed to 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).
The population was previously described as stable in the absence of evidence for any declines or substantial threats and thus, was not thought to approach the thresholds for Vulnerable under the population trend criterion (>30% decline over three generations, estimated at 11 years for this species). However, Vega Rivera et al. (2011) state that local extirpations and severe on-going deforestation suggest that this species’s population may be in decline. Specifically, that only 27% of tropical deciduous forest cover in 1990 in Mexico is left intact and that <10% of the area covered with deciduous forest is protected (Trejo and Dirzo 2000, CONANP 2009). It has also been suggested that severe habitat disturbance in the majority of dry forest zones in the Neotropics has greatly impacted avian deciduous forest specialists (Stotz et al. 1996). If there is evidence to suggest that the population size of this species has reduced by ≥30% in the past 11 years (one generation = 3.6 years), this species would warrant uplisting to Vulnerable under criterion A2bc of the IUCN Red List. Alternatively, if there is sufficient evidence to suggest that this species approaches (but does meet) this population trend threshold for Vulnerable, it would qualify for uplisting to Near Threatened.
Further information is required on the rate of habitat loss, the likely population size of this species and the rate of decline over the past 11 years, and comments on its proposed uplisting are welcome.
CONANP (Comisión Nacional de Áreas Naturales Protegidas) (2009) Áreas naturales protegidas federales de México. Edición 2008. Comisión Nacional de Áreas Naturales Protegidas. Morelia, Michoacán de Ocampo, México.
Stotz, D. F., Fitzpatrick, J. W., Parker III, T. A. and Moskovits. D. K. (1996) Neotropical birds: ecology and conservation. Chicago, IL: University of Chicago Press.
Trejo, I. and Dirzo, R. (2000) Deforestation of seasonally dry forest: a national and local analysis in Mexico. Biological Conservation 94: 133–142.
Vegra Rivera, J. H., Campos-Cerda, F. and Meiners, M (2011) Nesting Record and Population Phenology of the Flammulated Flycatcher (Deltarhynchus flammulatus). The Wilson Journal of Ornithology 123(4): 761-765.