6 thoughts on “Scaled Spinetail (Cranioleuca muelleri): Revise global status?”
In the Brazilian fauna extinction risk assessment conducted in 2018, the species was categorized as Near Threatened (NT).
Assessors: Alexandre Luis Padovan Aleixo; Alexander Charles Lees; Diego Mendes Lima; Edson Varga Lopes; Luís Fábio Silveira; Mario Eric Cohn Haft; Pablo Vieira Cerqueira; Vítor de Queiroz Piacentini.
Criterion A – in the assessment conducted in 2018, we found no long-term population estimate data to evaluate decline using observed data (a) and the decline of AOO and EOO (c) do not meet the thresholds for a threat category. It is not tolerant of habitat degradation and needs mature forests to survive, but shows slight tolerance to anthropized areas, occurring in floodplain areas with presence of cattle (A. Aleixo, M. Cohn-Haft, pers. comm., 2018).
The population of C. muelleri appears to be relatively small (Remsen, 2003). The species’ generation time has been estimated at 3.8 years (BirdLife International, 2018). Modelling done for the Amazon estimates a past habitat loss close to 30% between the years 2002 and 2013 (three generations) in this biome (Bird et al., 2012). Considering the time window of three generations in the past, it is suspected that there was population loss close to the thresholds for threatened status, but it is not possible to confirm the magnitude of this loss.
Note: Now in 2022, we understand that there are better remote sensing data that allow a better characterization of habitat loss. Furthermore, by using the new Bird et al. (2020) reference for generational time, the calculation of the time window will be smaller and will change the values of habitat loss for the species. In this sense, I believe that in 2022 the species can be characterised as Least Concern (LC) for this criterion.
Criterion B – The EOO calculations (126,155 km2) do not meet the thresholds for categorization as threatened. Its AOO (is greater than 2,000 km2), does not meet the thresholds for threatened categorisation. Least Concern (LC) for this criterion.
Criterion C – No information is available on population estimates. Also at the time of assessment (2018) no observed, estimated, projected or inferred population decline data was available. Only suspected data of the decline. Thus, not applicable to the IUCN criterion. Least Concern (LC) for this criterion.
Criterion D – No information on population estimates available. Of Concern (LC) for this criterion.
Criterion E – in the assessment conducted in 2018, we found no PVA data.
Bird, J.P.; Martin, R.; Akçakaya, H.R.; Gilroy, J.; Burfield, I.J.; Garnett, S.T.; Symes, A.; Taylor, J.; Sekercioglu, Ç.H. & Butchart, S.H. 2020. Generation lengths of the world’s birds and their implications for extinction risk. Conservation Biology, 34 (5): p.1252-1261.
Bird, J.P.; Buchanan, G.M.; Lees, A.C.; Clay, R.P.; Develey, P.F.; Yépez, I. & Butchart, S.H.M 2012. Integrating spatially explicit habitat projections into extinction risk assessments: a reassessment of Amazonian avifauna incorporating projected deforestation. Diversity and Distributions, 18 (3): p.273-281.
Although the last Brazilian assessment classified this species as NT, approaching A2c (ICMBio, 2018, unpublished), the habitat loss estimate was based on 2012 studies. The data presented here (Global Forest Watch) are current, with a more accurate estimate of habitat loss and LC seems more adequate.
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.
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.
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. Scaled Spinetail 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.
In the Brazilian fauna extinction risk assessment conducted in 2018, the species was categorized as Near Threatened (NT).
Assessors: Alexandre Luis Padovan Aleixo; Alexander Charles Lees; Diego Mendes Lima; Edson Varga Lopes; Luís Fábio Silveira; Mario Eric Cohn Haft; Pablo Vieira Cerqueira; Vítor de Queiroz Piacentini.
Criterion A – in the assessment conducted in 2018, we found no long-term population estimate data to evaluate decline using observed data (a) and the decline of AOO and EOO (c) do not meet the thresholds for a threat category. It is not tolerant of habitat degradation and needs mature forests to survive, but shows slight tolerance to anthropized areas, occurring in floodplain areas with presence of cattle (A. Aleixo, M. Cohn-Haft, pers. comm., 2018).
The population of C. muelleri appears to be relatively small (Remsen, 2003). The species’ generation time has been estimated at 3.8 years (BirdLife International, 2018). Modelling done for the Amazon estimates a past habitat loss close to 30% between the years 2002 and 2013 (three generations) in this biome (Bird et al., 2012). Considering the time window of three generations in the past, it is suspected that there was population loss close to the thresholds for threatened status, but it is not possible to confirm the magnitude of this loss.
Note: Now in 2022, we understand that there are better remote sensing data that allow a better characterization of habitat loss. Furthermore, by using the new Bird et al. (2020) reference for generational time, the calculation of the time window will be smaller and will change the values of habitat loss for the species. In this sense, I believe that in 2022 the species can be characterised as Least Concern (LC) for this criterion.
Criterion B – The EOO calculations (126,155 km2) do not meet the thresholds for categorization as threatened. Its AOO (is greater than 2,000 km2), does not meet the thresholds for threatened categorisation. Least Concern (LC) for this criterion.
Criterion C – No information is available on population estimates. Also at the time of assessment (2018) no observed, estimated, projected or inferred population decline data was available. Only suspected data of the decline. Thus, not applicable to the IUCN criterion. Least Concern (LC) for this criterion.
Criterion D – No information on population estimates available. Of Concern (LC) for this criterion.
Criterion E – in the assessment conducted in 2018, we found no PVA data.
Bird, J.P.; Martin, R.; Akçakaya, H.R.; Gilroy, J.; Burfield, I.J.; Garnett, S.T.; Symes, A.; Taylor, J.; Sekercioglu, Ç.H. & Butchart, S.H. 2020. Generation lengths of the world’s birds and their implications for extinction risk. Conservation Biology, 34 (5): p.1252-1261.
Bird, J.P.; Buchanan, G.M.; Lees, A.C.; Clay, R.P.; Develey, P.F.; Yépez, I. & Butchart, S.H.M 2012. Integrating spatially explicit habitat projections into extinction risk assessments: a reassessment of Amazonian avifauna incorporating projected deforestation. Diversity and Distributions, 18 (3): p.273-281.
Although the last Brazilian assessment classified this species as NT, approaching A2c (ICMBio, 2018, unpublished), the habitat loss estimate was based on 2012 studies. The data presented here (Global Forest Watch) are current, with a more accurate estimate of habitat loss and LC seems more adequate.
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.
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.
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. Scaled Spinetail 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.