Data Zone
Justification of Red List category
This species is known from a very small area of marshland surrounding a single Andean lake, where habitat quality is declining, mainly because of pollution and high grazing pressure. Recent studies suggest a population of around 4,100 mature individuals, but the population may be sensitive to human-induced changes of the water level. The species consequently qualifies as Endangered.
Population justification
Point counts with playback in February 2014 showed an average density of 62 individuals/km2, indicating a total of 6,200 individuals (Dinesen et al. 2017), which roughly equates to 4,100 mature individuals. This number is considerably higher than earlier estimates of 1,000-2,499 mature individuals. However, strong fluctuations in water levels may lead to population fluctuations, as high water levels may force many individuals to leave areas with vegetation cover (J. Fjeldså in litt. 2020).
Trend justification
A moderate and ongoing population decline is suspected to be occurring on the basis of the declining quality of habitat within the small range.
Laterallus tuerosi is endemic to the marshes and boggy shore meadows surrounding Lago de Junín, Junín, in the Andean highlands of central Peru. A recent survey suggests that it is present and fairly common in all sections of the wetland, over a minimum of 100 km2 (Dinesen et al. 2017, J. Fjeldså in litt. 2020).
This secretive waterbird inhabits the rushy marsh vegetation fringing Lago de Junín, at c. 4,080 m in the Andean highlands. It prefers fairly tall tussock grasses (Festuca dolichophylla) or sedges (Juncus balticus) in mosaics of shallow water, dry patches and small open spaces (Fjeldså 1983, Dinesen et al. 2017, J. Fjeldså in litt. 2020). Breeding is reported to occur at the end of the dry season, in September-October, and two eggs are laid.
Since at least 1955, Lago Junín has been affected by pollution and human-induced water-level changes, which may adversely affect the fringing vegetation. There has been strong desiccation of reed marshes, caused by drought and unsustainable water management by Electro Peru, and occasional flooding with highly acidic water from the Cerro de Pasco mines (J. Fjeldså in litt. to Taylor and van Perlo 1998). Large parts of the boggy shore meadows are strongly overgrazed by sheep and cattle, and do not provide vegetation cover for the species (J. Fjeldså in litt. 2020). Predation by Pampas Cats (Leopardus colocolo pajeros), Andean Fox (Lycalopex culpaeus) and dogs may be a significant problem, which is exacerbated by periods of drought when more of the marsh becomes accessible to the predators (Dinesen et al. 2017).
Conservation Actions Underway
Lago Junín is a national reserve, but this has not influenced mining and dam-building activities (O'Donnell and Fjeldså undated).
12-13 cm. Tiny, strikingly patterned rail. Dark slaty head, throat and underparts with black belly and vent, heavily barred white. Buff undertail-coverts. Dull rufous-brown back. Rest of upperparts dark brown, boldly barred white. Greenish-yellow legs. Voice Single chirrr notes. Males deliver a succession of chic notes ending with a falling slur. Females a low croo-croo-o.
Text account compilers
Hermes, C.
Contributors
Fjeldså, J., Symes, A., Benstead, P. & Sharpe, C.J.
Recommended citation
BirdLife International (2024) Species factsheet: Junin Rail Laterallus tuerosi. Downloaded from
https://datazone.birdlife.org/species/factsheet/junin-rail-laterallus-tuerosi 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.