5 thoughts on “Oaxaca Hummingbird (Eupherusa cyanophrys)”
Recent observations from the Miahuatlán slope (north slope of the Sierra Sur) indicate that the population extends across the entire Sierra Sur. The previously proposed separation into two distribution areas appears to be a misinterpretation, likely influenced by limited road access. This is supported by observations made by Jan Pierson on January 15, 2025, along the new highway between the two previously estimated areas.
Additional recent observations from San José del Pacífico, along with older photographic records from the same site, confirm that this species occurs on the northern side of the Sierra. An unconfirmed observation from Los Coatlánes further suggests that the species’ range may extend even beyond what is currently documented.
I would like to begin by clarifying that I am not a hummingbird specialist; my comments are based primarily on my experience in conservation and monitoring of various taxa.
I have reviewed the indicators and population information discussed in this forum, and indeed, these seem to suggest that the species may no longer require maintaining its Endangered status. However, to my understanding, there are currently no specific and robust studies assessing its actual population density, not even in localities where the species is apparently common.
Additionally, I conducted a preliminary exercise using records available through GBIF to compare the frequency of observations of the Oaxaca Hummingbird (Eupherusa cyanophrys) with those of the Mexican Hermit (Phaethornis mexicanus), a species whose distribution partially overlaps with that of the Oaxaca Hummingbird. Although this is a simple approximation and I recognize that it may be influenced by observation bias, sampling effort, and the processes through which records are incorporated into open-access platforms, I found that, from 2022 to the present, the Oaxaca Hummingbird has more records than the Mexican Hermit. Broadly speaking, this information appears to support the observations previously shared by several experts in this forum.
However, for the past several months, some colleagues and I have been working in different localities within the species’ range, particularly in Pluma Hidalgo. As part of these activities, we installed camera traps facing flowering plants and also carried out active searches through direct photography. Our data are still very limited and do not allow for conclusive inferences, since the sampling effort is low: only four camera traps have been operating continuously from January to the present.
Even with these limitations, the results obtained contrast markedly with the pattern observed in GBIF. Between January and April — the period for which we currently have systematized data — we obtained 42 records of the Mexican Hermit, only one record of the Oaxaca Hummingbird, and 210 records of the Cinnamon Hummingbird (Amazilia rutila).
Of course, these differences in frequency of occurrence cannot be interpreted directly as estimates of abundance or population density. Nevertheless, detection frequency has been used in numerous studies as an indirect indicator of such parameters. In this case, there are several important limitations: few sampling stations, a short monitoring period, and the absence of controls for relevant variables such as the plant species visited by each hummingbird. I fully recognize that this information is far from constituting definitive or publishable evidence; however, in the absence of robust studies capable of supporting a strong conclusion regarding the population status of the species, I believe these preliminary results may still be relevant for decision-making under the precautionary principle.
This translation was prepared with the assistance of ChatGPT.
Many thanks to everyone who has contributed to this discussion. We greatly appreciate the time and effort invested in commenting. The window for consultation is now closed and we are unable to accept any more comments until 22 May 2026. We will now analyse and interpret the information, and we will post a preliminary decision on this species’ Red List category on this page on 22 May 2026, when discussions will re-open.
Many thanks to Manuel and Francisco for their helpful comments. The comments by Manuel support a wider distribution of the species likely across the entire Sierra Sur and also support one continuous subpopulation.
The comments by Francisco, however, indicate that the species may not be common across this range and in some areas may be rare or absent despite seemingly suitable habitat. However, as mentioned by Francisco, further studies are required to determine environmental and other factors that may influence occupancy and density. Currently, there is insufficient information to estimate the population size.
We would like to reiterate that this assessment is not meant to reflect a genuine change in the species’ status but rather is a correction of the previous category based on new information. The previous assessment relied on a population estimate that was not informed by reliable quantitative or qualitative data, and the current population size is considered unknown. We will ensure the information provided in the above comments is captured in the final assessment.
Based on available information, our preliminary proposal for the 2026 Red List would be to adopt the proposed classifications outlined in the initial forum discussion.
There is now a period for further comments until the final deadline on 31 May 2026, after which the recommended categorisations will be put forward to IUCN.
The final 2026 Red List categories will be published on the BirdLife and IUCN websites in November 2026, following further checking of information relevant to the assessments by both BirdLife and IUCN.
Many thanks to everyone who has contributed to this discussion. We greatly appreciate the time and effort invested in commenting. The window for consultation is now closed and we are unable to accept any more comments. We will analyse and interpret the information, and a final decision on this species’ Red List category will be posted on this page on 8 June 2026.
Recent observations from the Miahuatlán slope (north slope of the Sierra Sur) indicate that the population extends across the entire Sierra Sur. The previously proposed separation into two distribution areas appears to be a misinterpretation, likely influenced by limited road access. This is supported by observations made by Jan Pierson on January 15, 2025, along the new highway between the two previously estimated areas.
Additional recent observations from San José del Pacífico, along with older photographic records from the same site, confirm that this species occurs on the northern side of the Sierra. An unconfirmed observation from Los Coatlánes further suggests that the species’ range may extend even beyond what is currently documented.
I would like to begin by clarifying that I am not a hummingbird specialist; my comments are based primarily on my experience in conservation and monitoring of various taxa.
I have reviewed the indicators and population information discussed in this forum, and indeed, these seem to suggest that the species may no longer require maintaining its Endangered status. However, to my understanding, there are currently no specific and robust studies assessing its actual population density, not even in localities where the species is apparently common.
Additionally, I conducted a preliminary exercise using records available through GBIF to compare the frequency of observations of the Oaxaca Hummingbird (Eupherusa cyanophrys) with those of the Mexican Hermit (Phaethornis mexicanus), a species whose distribution partially overlaps with that of the Oaxaca Hummingbird. Although this is a simple approximation and I recognize that it may be influenced by observation bias, sampling effort, and the processes through which records are incorporated into open-access platforms, I found that, from 2022 to the present, the Oaxaca Hummingbird has more records than the Mexican Hermit. Broadly speaking, this information appears to support the observations previously shared by several experts in this forum.
However, for the past several months, some colleagues and I have been working in different localities within the species’ range, particularly in Pluma Hidalgo. As part of these activities, we installed camera traps facing flowering plants and also carried out active searches through direct photography. Our data are still very limited and do not allow for conclusive inferences, since the sampling effort is low: only four camera traps have been operating continuously from January to the present.
Even with these limitations, the results obtained contrast markedly with the pattern observed in GBIF. Between January and April — the period for which we currently have systematized data — we obtained 42 records of the Mexican Hermit, only one record of the Oaxaca Hummingbird, and 210 records of the Cinnamon Hummingbird (Amazilia rutila).
Of course, these differences in frequency of occurrence cannot be interpreted directly as estimates of abundance or population density. Nevertheless, detection frequency has been used in numerous studies as an indirect indicator of such parameters. In this case, there are several important limitations: few sampling stations, a short monitoring period, and the absence of controls for relevant variables such as the plant species visited by each hummingbird. I fully recognize that this information is far from constituting definitive or publishable evidence; however, in the absence of robust studies capable of supporting a strong conclusion regarding the population status of the species, I believe these preliminary results may still be relevant for decision-making under the precautionary principle.
This translation was prepared with the assistance of ChatGPT.
Many thanks to everyone who has contributed to this discussion. We greatly appreciate the time and effort invested in commenting. The window for consultation is now closed and we are unable to accept any more comments until 22 May 2026. We will now analyse and interpret the information, and we will post a preliminary decision on this species’ Red List category on this page on 22 May 2026, when discussions will re-open.
Preliminary proposal
Many thanks to Manuel and Francisco for their helpful comments. The comments by Manuel support a wider distribution of the species likely across the entire Sierra Sur and also support one continuous subpopulation.
The comments by Francisco, however, indicate that the species may not be common across this range and in some areas may be rare or absent despite seemingly suitable habitat. However, as mentioned by Francisco, further studies are required to determine environmental and other factors that may influence occupancy and density. Currently, there is insufficient information to estimate the population size.
We would like to reiterate that this assessment is not meant to reflect a genuine change in the species’ status but rather is a correction of the previous category based on new information. The previous assessment relied on a population estimate that was not informed by reliable quantitative or qualitative data, and the current population size is considered unknown. We will ensure the information provided in the above comments is captured in the final assessment.
Based on available information, our preliminary proposal for the 2026 Red List would be to adopt the proposed classifications outlined in the initial forum discussion.
There is now a period for further comments until the final deadline on 31 May 2026, after which the recommended categorisations will be put forward to IUCN.
The final 2026 Red List categories will be published on the BirdLife and IUCN websites in November 2026, following further checking of information relevant to the assessments by both BirdLife and IUCN.
Many thanks to everyone who has contributed to this discussion. We greatly appreciate the time and effort invested in commenting. The window for consultation is now closed and we are unable to accept any more comments. We will analyse and interpret the information, and a final decision on this species’ Red List category will be posted on this page on 8 June 2026.