| 2009 IUCN Red List Category (as evaluated by BirdLife International - the official Red List Authority for birds for IUCN): Least Concern Justification 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). Despite the fact that the population trend appears to be decreasing, the decline is not believed to be sufficiently rapid to approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size is very large, and hence does not 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). For these reasons the species is evaluated as Least Concern. Family/Sub-family Ramphastidae Species name author (Gould, 1834) Taxonomic source(s) AOU checklist (1998 + supplements), SACC (2005 + updates), Sibley and Monroe (1990, 1993), Stotz et al. (1996) Taxonomic note Aulacorhynchus prasinus (Sibley and Monroe 1990, 1993) was split into prasinus, wagleri, caeruleogularis, cognatus, lautus, albivitta and atrogularis by Navarro et al. (2001), on the basis mainly of differences in bill pattern and throat colour, but this treatment is not followed by SACC (2005), or the BirdLife Taxonomic Working Group as it is considered premature. The authors themselves state that their summary of variation of these characters is preliminary and call for more work. Neither do they consider vocal evidence nor within (sub)species variation. While recognising that this complex shows considerable variation, and that species-level recognition may prove to be appropriate as the authors indicate, the BirdLife Taxonomic Working Group feel that the small toucans are a group which show a great deal of marked geographic variation such that species-level reassessments should occur across all currently recognised species rather than occurring piecemeal.
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