Herpsilochmus gentryi 


Taxonomy [top]

Kingdom Phylum Class Order Family
Animalia Chordata Aves Passeriformes Thamnophilidae

Scientific Name: Herpsilochmus gentryi
Species Authority: Whitney & Alvarez Alonso, 1998
Common Name(s):
English Ancient Antwren
Taxonomic Source(s): SACC. 2006. A classification of the bird species of South America. Available at: #
Identification information:

Assessment Information [top]

Red List Category & Criteria: Near Threatened ver 3.1
Year Published: 2012
Date Assessed: 2012-05-01
Assessor(s): BirdLife International
Reviewer(s): Butchart, S. & Symes, A.
Facilitator/Compiler(s): Butchart, S., Gilroy, J., Sharpe, C J
This habitat specialist is listed as Near Threatened as it is known from a small range, and is probably declining. It is likely to be at increased risk from human encroachment in the near future owing to rising population pressures within its range. However, the range is not yet severely fragmented or restricted to few locations. For these reasons, the species is classified as Near Threatened.

Previously published Red List assessments:
2008 Near Threatened (NT)
2004 Near Threatened (NT)
2000 Lower Risk/near threatened (LR/nt)
1994 Not Recognized (NR)
1988 Not Recognized (NR)

Geographic Range [top]

Range Description: Herpsilochmus gentryi occurs in the Marañón, Tigre, Corrientes, Pucacuro and Pastaza drainages in north-central Peru (Loreto) and east Ecuador (Pastaza), where it is common at a moderate number of sites since its discovery in the mid-1990s. It was previously thought to occur only in two rare and patchy types of terra firme forest, growing on hill-top nutrient-poor soils, but a third type is apparently inhabited in Ecuador.

Countries occurrence:
Ecuador; Peru
Continuing decline in area of occupancy (AOO): Yes
Extreme fluctuations in area of occupancy (AOO): No
Estimated extent of occurrence (EOO) - km2: 9500
Continuing decline in extent of occurrence (EOO): Unknown
Extreme fluctuations in extent of occurrence (EOO): No
Number of Locations: 11-100
Continuing decline in number of locations: Unknown
Extreme fluctuations in the number of locations: No
Upper elevation limit (metres): 200
Range Map: Click here to open the map viewer and explore range.

Population [top]

Population: The population size of this species has not been quantified, but it is described as locally common in general, being rare and local in Ecuador but locally fairly common in Peru.

Trend Justification:  This species is suspected to lose 3.5% of suitable habitat within its distribution over three generations (14 years) based on a model of Amazonian deforestation (Soares-Filho et al. 2006, Bird et al. 2011). Although susceptible to fragmentation and/or edge effects, it is therefore suspected to decline by <25% over three generations.
Current Population Trend: Decreasing
Additional data:
Number of mature individuals: Unknown Continuing decline of mature individuals: Unknown
Extreme fluctuations: No Population severely fragmented: No
Continuing decline in subpopulations: Unknown
Extreme fluctuations in subpopulations: No All individuals in one subpopulation: No
No. of individuals in largest subpopulation: 100

Habitat and Ecology [top]

Habitat and Ecology: It occurs in canopy and subcanopy of humid tropical forest up to 200 m. Apparently restricted to terra firme forest growing on nutrient-poor podzolic or quartzitic soils, as well as on high, dry ridgetops.

Systems: Terrestrial
Continuing decline in area, extent and/or quality of habitat: Yes
Generation Length (years): 4.8
Movement patterns: Not a Migrant

Threats [top]

Major Threat(s): In the Iquitos area, Peru, an increasing amount of its habitat is being cleared owing to human population growth. Much of the remainder of its range is remote and subject to little human pressure.

Conservation Actions [top]

Conservation Actions: Conservation Actions Underway
It is well protected in Ecuador, by the Kapawi Ecological Reserve, whilst the Allapahuayo-Mishana Reserved Zone in Peru encompasses large areas of suitable habitat.

Conservation Actions Proposed
Conduct surveys of suitable habitats within and surrounding the known range to determine its true distribution and abundance. Increase the area of suitable habitat that has protected status, particularly near Iquitos.

Citation: BirdLife International. 2012. Herpsilochmus gentryi. The IUCN Red List of Threatened Species 2012: e.T22724610A38083354. . Downloaded on 25 November 2015.
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