VU
Pampas Meadowlark Leistes defilippii



Taxonomy

Taxonomic note

Leistes defilippii (del Hoyo and Collar 2016) was previously placed in the genus Sturnella following SACC (2005 & updates); Sibley and Monroe (1990, 1993); Stotz et al. (1996).

 

Taxonomic source(s)
del Hoyo, J., Collar, N.J., Christie, D.A., Elliott, A., Fishpool, L.D.C., Boesman, P. and Kirwan, G.M. 2016. HBW and BirdLife International Illustrated Checklist of the Birds of the World. Volume 2: Passerines. Lynx Edicions and BirdLife International, Barcelona, Spain and Cambridge, UK.
SACC. 2005 and updates. A classification of the bird species of South America. Available at: https://www.museum.lsu.edu/~Remsen/SACCBaseline.htm.

IUCN Red List criteria met and history
Red List criteria met
Critically Endangered Endangered Vulnerable
- A2bc+3bc+4bc A2bc+3bc+4bc

Red List history
Year Category Criteria
2020 Vulnerable A2bc+3bc+4bc
2018 Vulnerable A2ce+3ce+4ce
2016 Vulnerable A2ce+3ce+4ce;B1ab(i,ii,iii,iv,v)
2012 Vulnerable A2ce+3ce+4ce;B1ab(i,ii,iii,iv,v)
2008 Vulnerable B1a+b(i,ii,iii,v)
2007 Vulnerable
2004 Vulnerable
2000 Vulnerable
1994 Endangered
1988 Threatened
Species attributes

Migratory status full migrant Forest dependency does not normally occur in forest
Land-mass type continent
Average mass -
Range

Estimate Data quality
Extent of Occurrence (breeding/resident) 127,000 km2 medium
Extent of Occurrence (non-breeding) 270,000 km2 medium
Severely fragmented? no -
Population
Estimate Data quality Derivation Year of estimate
Population size 4000-6000 mature individuals medium estimated 2014
Population trend decreasing poor inferred 2011-2021
Rate of change over the past 10 years/3 generations (longer of the two periods) 9-69,30-49% - - -
Rate of change over the future 10 years/3 generations (longer of the two periods) 9-69,30-49% - - -
Rate of change over the past & future 10 years/3 generations (longer of the two periods) 9-69,30-49% - - -
Generation length 2.98 years - - -
Number of subpopulations 1-4 - - -
Percentage of mature individuals in largest subpopulation 40-100% - - -

Population justification: In Argentina, surveys in southwest Buenos Aires and adjacent areas of La Pampa in 1992-1996 produced an estimated population size of 7,500 individuals (approximately equivalent to 5,000 mature individuals; Tubaro and Gabelli 1993, 1999). Less than 29% of apparently suitable sites were occupied by the species. The species's extent of occurrence was estimated to be approximately 8,000 km2 (Tubaro and Gabelli 1999). More extensive surveys in the same region in 1999 produced a population size estimate of at least 28,000 individuals (approximately equivalent to 18,667 mature individuals) and an extent of occurrence of 4,810km2, indicating a range contraction of c.30% since 1992-1996 (Gabelli et al. 2004). The higher population estimate was attributed to a greater sampling effort than that used in the previous study. More recently, the Argentinian national Red List states that the estimate by Gabelli et al. (2004) was likely an overestimate, and that surveys in 2011-2014 found a population size 10% smaller than that estimated in 1992-1996 (MAyDS and Aves Argentinas 2017), which would equate to a population size of 6,750 individuals, or approximately 4,500 mature individuals. The population in Argentina in 2017 was considered to be smaller than 2,500 mature individuals (MAyDS and Aves Argentinas 2017), but the basis of this figure was not provided. The current population size in Argentina is therefore estimated to fall within the band 4,000-5,000 mature individuals.

In Uruguay, surveys in the Arerunguá region, Salto, and surrounding areas in 2003 estimated a regional population of 78-90 pairs (equivalent to 156-180 mature individuals; Azpiroz 2005). Subsequent studies revised this figure to c.150-200 pairs (equivalent to 300-400 mature individuals) in 2012 (Azpiroz and Cozzani 2017). A further population of 50-70 individuals (equivalent to 33-47 mature individuals) was recently discovered in Tacuarembó (Azpiroz and Cozzani 2017). However, during the 2016 breeding season, only five breeding pairs were recorded in the Arerunguá area, in an area thought to have contained 100-140 pairs in the last decade (Azpiroz and Cozzani 2017). During the 2017 breeding season, 5-20 pairs (approximately equivalent to 10-40 mature individuals), plus a post-breeding group of around 120 individuals (many of which were juveniles) were recorded in the area (Azpiroz and Cozzani 2017). The population size in Uruguay is therefore likely to fall within the band 50-200 mature individuals. The global population size is therefore placed in the range 4,000-6,000 mature individuals.

In Argentina, population densities were estimated to be 50 individuals per km2 (C.I. 20-126) in natural grasslands in the southwest of the surveyed region, and 4 individuals per km2 (C. I. 0.8-22) in the northeast (Gabelli et al. 2004). Surveys of grasslands and cultivated areas in Uruguay in 2004-2005 recorded mean population densities of 13.6 individuals per km2 (C. I. 5.4-34.3) in grasslands grazed by cattle and sheep, and 1.5 individuals per km2 (C. I. 0.4-5.8) in grasslands grazed by cattle and Pampas Deer (Azpiroz and Blake 2009). Pretelli et al. (2013) estimated a density of 5 individuals per km2 of wintering individuals, during surveys of Cortaderia selloana grasslands in the south-east Pampas region, Argentina.

The subpopulations in Bahia Blanca (Argentina) and Arerungua (Uruguay) are around 900 km apart. A study of the species's genetics estimated than an average of 2.57 individuals migrate between the two subpopulations per year, and that the two populations have four genetic clusters: two in the Arerungua population, one in the Bahia Blanca population, and another shared between the two (Repetto 2017). There are therefore considered to be 1-4 subpopulations.

Trend justification: Recent estimates for the population size in Argentina have included: c.7,500 individuals (equivalent to 5,000 mature individuals) in 1992-1996 (Tubaro and Gabelli 1999) and 28,000 individuals (equivalent to 18,667 mature individuals) in 1999 (Gabelli et al. 2004). The species's extent of occurrence in Argentina was also found to have contracted by 30% between 1993-1996 and 1999 (Gabelli et al. 2004), which would equate to a reduction of 55% over ten years. However, the Argentinian Red List (MAyDS and Aves Argentina 2017) states that the 1999 population estimate was an overestimate, and that surveys in 2011-2014 have found a population size 10% smaller than that estimated in 1992-1996, which would approximately equate to 4,500 mature individuals. This rate of decline would equate to a reduction of 5.5% over ten years, assuming the 1992-1995 estimate was accurate, or a 64% reduction over ten years if the 1999 population estimate was correct. The Argentinian Red List also states that the current population in Argentina is less than 2,500 mature individuals, but the basis of this estimate is not described (MAyDS and Aves Argentina 2017). 

In the Arerunguá area in Uruguay, there were an estimated 300-400 mature individuals in 2012 (Azpiroz and Cozzani 2017). A further population of 50-70 individuals (equivalent to 33-47 mature individuals) was recently discovered in Tacuarembó (Azpiroz and Cozzani 2017). However, during the 2016 breeding season, only five breeding pairs were recorded in the Arerunguá area, in an area thought to have contained 100-140 pairs in the last decade (Azpiroz and Cozzani 2017). During the 2017 breeding season, 5-20 pairs, plus a post-breeding group of around 120 individuals (many of which were juveniles) were recorded in the area (Azpiroz and Cozzani 2017). Assuming the population size declined from 300-450 mature individuals in 2012, to 50-200 mature individuals in 2017, this rate of decline would equate to a reduction of between 56% and 99% over ten years.

Based on the evidence described, the species is inferred to have undergone an overall reduction of between 9% and 69% across the past ten years, with the best estimate tentatively placed in the band 30-49%. Current trends are assumed to continue over the next decade.


Country/territory distribution
Country/Territory Presence Origin Resident Breeding visitor Non-breeding visitor Passage migrant
Argentina extant native yes
Brazil extinct native yes
Uruguay extant native yes

Important Bird and Biodiversity Areas (IBA)
Country/Territory IBA Name
Argentina Caldenal del Sudoeste de Buenos Aires
Argentina Pastizales de La Travesía y Buena Esperanza
Argentina Villa Iris, Chasicó, Napostá
Argentina Villa marítima El Cóndor
Uruguay El Tapado Grasslands

Habitats & altitude
Habitat (level 1) Habitat (level 2) Importance Occurrence
Grassland Temperate major resident
Altitude 0 - 900 m Occasional altitudinal limits  

Threats & impact
Threat (level 1) Threat (level 2) Impact and Stresses
Agriculture & aquaculture Annual & perennial non-timber crops - Agro-industry farming Timing Scope Severity Impact
Ongoing Whole (>90%) Rapid Declines High Impact: 8
Stresses
Ecosystem degradation, Ecosystem conversion
Agriculture & aquaculture Annual & perennial non-timber crops - Small-holder farming Timing Scope Severity Impact
Ongoing Majority (50-90%) Slow, Significant Declines Medium Impact: 6
Stresses
Ecosystem degradation, Ecosystem conversion
Agriculture & aquaculture Livestock farming & ranching - Agro-industry grazing, ranching or farming Timing Scope Severity Impact
Ongoing Whole (>90%) Rapid Declines High Impact: 8
Stresses
Ecosystem degradation, Ecosystem conversion
Agriculture & aquaculture Livestock farming & ranching - Small-holder grazing, ranching or farming Timing Scope Severity Impact
Ongoing Whole (>90%) Slow, Significant Declines Medium Impact: 7
Stresses
Ecosystem degradation, Ecosystem conversion, Reduced reproductive success
Agriculture & aquaculture Wood & pulp plantations - Agro-industry plantations Timing Scope Severity Impact
Ongoing Minority (<50%) Very Rapid Declines Medium Impact: 7
Stresses
Ecosystem conversion
Residential & commercial development Housing & urban areas Timing Scope Severity Impact
Ongoing Minority (<50%) Negligible declines Low Impact: 4
Stresses
Ecosystem degradation, Ecosystem conversion
Residential & commercial development Tourism & recreation areas Timing Scope Severity Impact
Future Minority (<50%) Negligible declines No/Negligible Impact: 2
Stresses
Ecosystem degradation, Ecosystem conversion

Utilisation
Purpose Scale
Pets/display animals, horticulture international

Recommended citation
BirdLife International (2024) Species factsheet: Pampas Meadowlark Leistes defilippii. Downloaded from https://datazone.birdlife.org/species/factsheet/pampas-meadowlark-leistes-defilippii on 23/11/2024.
Recommended citation for factsheets for more than one species: BirdLife International (2024) IUCN Red List for birds. Downloaded from https://datazone.birdlife.org/species/search on 23/11/2024.