Wied’s Tyrant-manakin (Neopelma aurifrons): Revise global status?

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5 Responses to Wied’s Tyrant-manakin (Neopelma aurifrons): Revise global status?

  1. Diego Mendes Lima says:

    In the assessment of the risk of extinction of the Brazilian fauna carried out in 2019, the species was categorized as Endangered (EN), by the B2ab(ii,iii,v) criterion.

    Evaluators: Caio Graco Machado Santos, Diego Mendes Lima, Ciro Ginez Albano, Glayson Ariel Bencke, José Fernando Pacheco, Luís Fábio Silveira, Vítor de Queiroz Piacentini and Wagner Nogueira Alves.

    Criterion A: – in the 2019 assessment, we did not find long-term population estimates data to track the decline by observed data (a) and the decline in AOO and EOO (c) do not reach the thresholds for a threat category. Habitat loss calculations performed with tools available on MapBioma (https://mapbiomas.org/) in the generational time of the species does not reach the population reduction threshold due to habitat loss in its range.

    Criterion B – EOO calculations (118,513 km2) do not meet thresholds for threatened categorization. However, its AOO (320 km2), calculated by superimposing a grid with 4 km2 grid squares to the current confirmed, inferred and suspected record points, adding the grid area, meets the Endangered category threshold (EN), by the B2ab(ii,iii,v) criterion. The species occurs in a severely fragmented forest matrix with more than 50% of its population separated by a great distance, with no gene flow. There are local extinctions in Bahia and in the state of Rio de Janeiro in fragments where the species is no longer registered. In addition, there is a continued decline in population due to the loss of occupied area and habitat quality due to human activities, especially agriculture, urban expansion and forest fires.

    Criterion C – in the assessment carried out in 2019, we did not find observed, estimated, projected and inferred data on the number of mature individuals and respective population decline.

    Criterion D – in the assessment carried out in 2019, we did not find population data on mature individuals and their AOO is greater than 20 km2

    Criterion E: in the assessment carried out in 2019, we did not find PVA data.

    JUSTIFICATION: Neopelma aurifrons is endemic to Brazil, originally occurring from southern Bahia and eastern Minas Gerais to Rio de Janeiro. Local extinctions are known for the coast of Bahia and the state of Rio de Janeiro. The area of ​​occupation (AOO) of the species was calculated at 320 km2. The population is severely fragmented having more than 50% of its total occupied area separated from other fragments by a great distance and individuals do not move between fragments outside their habitat. There is continued population decline due to habitat loss due to forest conversion into areas for agriculture, illegal logging, urban sprawl and forest fires. Thus, N. aurifrons was assessed as Endangered (EN) by the B2ab(ii,iii,v) criterion.

  2. Ben Phalan says:

    In the National Red List assessment, this single-country endemic was previously uplisted from NT to Endangered, on the basis of an estimated population of less than 2,500 mature individuals and ongoing decline. This status was maintained in 2019, this time based on an estimate of AOO with input from experienced ornithologists who know the species and the state of its remaining habitat better than anyone else. It is clear that the methods used to estimate AOO in the national assessment and here were quite different, with the former including all current confirmed, inferred and suspected record points, and the latter apparently including all forest cover. While the first method might result in an underestimate of AOO, the second seems certain to give a large overestimate for a species like this, which is dependent on high-quality habitat and has already suffered local extinctions.

    My suggestion would be either to uplist this species from VU to EN, for consistency with the National Red List, or at least to pend a decision on this species until a more precise estimate of population and suitable habitat is available (with, for example, more details of how “inferred and suspected” record points were identified in the national assessment). Downlisting would widen the inconsistency between national and global Red Lists, and I do not think that would be appropriate without stronger evidence. I’m willing to help with a more systematic evaluation of the available data, if needed.

  3. Red List Team (BirdLife International) says:

    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. We will analyse and interpret the new information and post a preliminary decision on this species’s Red List status on this page in early July.

    Thank you once again,
    BirdLife Red List Team

  4. Red List Team (BirdLife International) says:

    Preliminary proposal

    Based on available information, our preliminary proposal for the 2021 Red List would be to list Wied’s Tyrant-manakin as Near Threatened, approaching the thresholds for listing as threatened under Criteria B2ab(i,ii,iii,iv,v), C2a(i) and D1 .

    This is a difficult assessment primarily because of the limited information available on the current population size and structure. It has a fragmented distribution and recent records are in patches of forest that are mostly distant from one another, and many of which appear too small to support many individuals. Remapping the range to exclude locations for which there have been no records in the past ten years (including Rio de Janeiro state, Sooretama and Diamantina NP), and restricting occupied patches to those directly linked to recent records further reduces the suspected Area of Occupancy (AOO) to 1,088 km2. This remains higher than the value given in the National Red List assessment, which can only be due to a larger number of contiguous forested squares being assigned as occupied than were considered ‘confirmed, inferred and suspected record points’. For example, the entire area of Rio Doce State Park is included (359.7 km2). If converted to 2 x 2 km2 grid squares, this area sums to 452 km2, considerably larger than the total AOO given in the National Red List (320 km2). Loures-Ribeiro et al. (2011) had around 60 records within Rio Doce SP from 72 survey points in two plots (primary and secondary) each sampled 6 times, with frequency of encounter in the primary plot double that of the secondary plot. This strongly indicates that if an additional plot were placed in another part of the park, the species would also be encountered. Given there was a contrast in habitat quality, and a species response in terms of encounter rate to that difference, there is a good reason to infer presence elsewhere in the park. A second area of uncertainty is in Espirito Santo: there are frequent records from around Santa Teresa and as noted in Augusto Ruschi Biological Reserve, but it is noted to be very localised. To the south of this area is a highly fragmented landscape that retains relatively high wooded cover. Much is likely unsuitable, but there are recent records derived from apparently spontaneous checking of fragments near Venda Nova do Imigrante, Domingos Martins and Duas Bocas Biological Reserve (eBird 2021). Such a spread of records indicates either that this is the detection of dispersing birds from the occupied sites as defined in the National Red List, or there is wider occurrence at low density in a greater number of patches (which may still be too small for long-term persistence). For this assessment, suspected occupied patches have been kept as those with recent records, more conservative than assuming presence in similar patches interposed between sites with recent occurrence records.

    Determining whether the species is ‘Severely Fragmented’ is key to this assessment. In terms of the distribution of the area of mapped occupancy, there are two larger blocks: Rio Doce SP and the area around Santa Teresa and Augusto Ruschi BR. These two areas constitute 60% of the mapped occupied area. If, these populations are sufficient to be considered viable (which is accepted here), then less than half the population is inferred to occur in subpopulations that are likely to be too small to be sustained and too distant to be rescued by immigration. This assumes all other subpopulations are unconnected, also a conservative position. However, given the uncertainty over population size, should the population around Santa Teresa and Augusto Ruschi reduce it may rapidly become small enough to be considered unsustainable. This uncertainty allows the consideration that the population approaches ‘Severely Fragmented’, as noted in the initial proposal. The assessment of the number of locations is unchanged.

    Consequently, the preliminary proposal for the 2021 Red List is to adopt the proposed classification from the initial forum discussion, but the comments received and the reappraisal of recent occurrences indicates that the species also approaches listing as Threatened under Criterion B2ab(i,ii,iii,iv,v).

    There is now a period for further comments until the final deadline in mid-July, after which the recommended categorisations will be put forward to IUCN.

    The final 2021 Red List categories will be published on the BirdLife and IUCN websites in December 2021, following further checking of information relevant to the assessments by both BirdLife and IUCN.

  5. Red List Team (BirdLife International) says:

    Recommended categorisation to be put forward to IUCN

    The final categorisation for this species has not changed. Wied’s Tyrant-manakin is recommended to be listed as Near Threatened, approaching the threshold for listing as threatened under Criteria B2ab(i,ii,iii,iv,v); C2a(i); D1.

    Many thanks for everyone who contributed to the 2021 GTB Forum process. The final 2021 Red List categories will be published on the BirdLife and IUCN websites in December 2021, following further checking of information relevant to the assessments by both BirdLife and IUCN.

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