6 thoughts on “Partridge Pigeon (Geophaps smithii): Revise global status?”
Hi
I have been working on the Western subspecies of the partridge pigeon and have calculated a few of these variables for my work. I have found EOO to be equivalent to 26,400 km2 and AOO equivalent to 252 km2. These were calculated via alpha hulls using the ConR package in R statistical program. Happy to give more information surrounding these analyses and data if needed.
I also noticed you have listed the generation length as 4.7 years (and im happy to be persuaded this is correct) however the red list page for the species lists it as 5.6 years (https://www.iucnredlist.org/species/22690689/93283582).
As stated by Patrick, we have new data on G. smith blaauwi showing it has suffered a a 43.7% retraction in its EOO from its historical distribution. We argue in our pending paper that it warrants a vulnerable listing. Given that, a case to downcast for the species as. whole, is contingent upon the status of G. smith smith being stable and increasing enough to offset the western sub-species. Given the same threats apply to both species this does not seem warranted and we suggest that any proposal to downcast is too preliminary and requires further justification.
Many thanks to everyone who has contributed to this discussion. We greatly appreciate the time and effort invested by so many people in commenting. The window for consultation is now closed and we are unable to accept any more comments until 21 February 2022. We will now analyse and interpret the new information, and we will post a preliminary decision on this species’s Red List status on this page on 21 February 2022, when discussions will re-open.
Based on available information, our preliminary proposal for the 2022.1 Red List would be to adopt the proposed classifications outlined in the initial forum discussion. The generation length of 4.7 years used follows the methodology of Bird et al. (2020).
The population size of G. s. blaawi is estimated to be much smaller than that of the nominate subspecies, thus is less likely to affect the global trend of the species. The nominate subspecies, although facing similar threats, is currently not thought to be declining at a rate exceeding or approaching 30% over three generations 14.1 years (threshold under Criterion A). Combining both taxa as is required for a global assessment of its Red List status, the species does not approach thresholds for any other Criterion, thus remains proposed to be listed as Least Concern. Following information received by P. Williams via email, the map has been updated.
There is now a period for further comments until the final deadline on 27 February 2022, after which the recommended categorisations will be put forward to IUCN.
The final 2022.1 Red List categories will be published on the BirdLife and IUCN websites in July 2022, following further checking of information relevant to the assessments by both BirdLife and IUCN.
References
Bird, J.P., Martin, R., Akçakaya, H.R., Gilroy, J., Burfield, I.J., Garnett, S.G., Symes, A., Taylor, J., Şekercioğlu, Ç.H. and Butchart, S.H.M. 2020. Generation lengths of the world’s birds and their implications for extinction risk. Conservation Biology 34(5): 1252-1261. DOI: 10.1111/cobi.13486.
Many thanks to everyone who has contributed to this discussion. We greatly appreciate the time and effort invested by so many people in commenting. The window for consultation is now closed and we are unable to accept any more comments. We will analyse and interpret the new information, and we will post a final decision on this species’ Red List status on this page on 7 March 2022.
Recommended categorisation to be put forward to IUCN
The final categorisation for this species has not changed. Partridge Pigeon is recommended to be listed as Least Concern.
Many thanks for everyone who contributed to the 2022.1 GTB Forum process. The final 2022.1 Red List categories will be published on the BirdLife and IUCN websites in July 2022, following further checking of information relevant to the assessments by both BirdLife and IUCN.
Hi
I have been working on the Western subspecies of the partridge pigeon and have calculated a few of these variables for my work. I have found EOO to be equivalent to 26,400 km2 and AOO equivalent to 252 km2. These were calculated via alpha hulls using the ConR package in R statistical program. Happy to give more information surrounding these analyses and data if needed.
I also noticed you have listed the generation length as 4.7 years (and im happy to be persuaded this is correct) however the red list page for the species lists it as 5.6 years (https://www.iucnredlist.org/species/22690689/93283582).
As stated by Patrick, we have new data on G. smith blaauwi showing it has suffered a a 43.7% retraction in its EOO from its historical distribution. We argue in our pending paper that it warrants a vulnerable listing. Given that, a case to downcast for the species as. whole, is contingent upon the status of G. smith smith being stable and increasing enough to offset the western sub-species. Given the same threats apply to both species this does not seem warranted and we suggest that any proposal to downcast is too preliminary and requires further justification.
Many thanks to everyone who has contributed to this discussion. We greatly appreciate the time and effort invested by so many people in commenting. The window for consultation is now closed and we are unable to accept any more comments until 21 February 2022. We will now analyse and interpret the new information, and we will post a preliminary decision on this species’s Red List status on this page on 21 February 2022, when discussions will re-open.
Preliminary proposal
Based on available information, our preliminary proposal for the 2022.1 Red List would be to adopt the proposed classifications outlined in the initial forum discussion. The generation length of 4.7 years used follows the methodology of Bird et al. (2020).
The population size of G. s. blaawi is estimated to be much smaller than that of the nominate subspecies, thus is less likely to affect the global trend of the species. The nominate subspecies, although facing similar threats, is currently not thought to be declining at a rate exceeding or approaching 30% over three generations 14.1 years (threshold under Criterion A). Combining both taxa as is required for a global assessment of its Red List status, the species does not approach thresholds for any other Criterion, thus remains proposed to be listed as Least Concern. Following information received by P. Williams via email, the map has been updated.
There is now a period for further comments until the final deadline on 27 February 2022, after which the recommended categorisations will be put forward to IUCN.
The final 2022.1 Red List categories will be published on the BirdLife and IUCN websites in July 2022, following further checking of information relevant to the assessments by both BirdLife and IUCN.
References
Bird, J.P., Martin, R., Akçakaya, H.R., Gilroy, J., Burfield, I.J., Garnett, S.G., Symes, A., Taylor, J., Şekercioğlu, Ç.H. and Butchart, S.H.M. 2020. Generation lengths of the world’s birds and their implications for extinction risk. Conservation Biology 34(5): 1252-1261. DOI: 10.1111/cobi.13486.
Many thanks to everyone who has contributed to this discussion. We greatly appreciate the time and effort invested by so many people in commenting. The window for consultation is now closed and we are unable to accept any more comments. We will analyse and interpret the new information, and we will post a final decision on this species’ Red List status on this page on 7 March 2022.
Recommended categorisation to be put forward to IUCN
The final categorisation for this species has not changed. Partridge Pigeon is recommended to be listed as Least Concern.
Many thanks for everyone who contributed to the 2022.1 GTB Forum process. The final 2022.1 Red List categories will be published on the BirdLife and IUCN websites in July 2022, following further checking of information relevant to the assessments by both BirdLife and IUCN.