NT
Northern Silvery Grebe Podiceps juninensis



Justification

Justification of Red List category
This species has recently become localised in parts of its range, and is suspected to be undergoing moderately rapid population declines owing to the loss and degradation of wetland habitat, the impact of invasive species and hunting. It is therefore classified as Near Threatened, but better trend data and understanding of threats may lead to a further reclassification of its status.

Population justification
The overall population size has not been quantified.

Trend justification
The species has undergone very rapid declines at some sites but has increased at others. The overall trend is precautionarily suspected to be a moderately rapid decline over three generations (14.7 years) owing to habitat degradation and the impact of invasive species.

Distribution and population

Podiceps juninensis inhabits the Andean highlands from Antofagasta (and occasionally Santiago) in northern Chile and Catamarca in north-western Argentina to Junín in Peru (casually descending to the coast of Peru), with a few breeding sites further north in Peru, Ecuador and the Cordillera Central of Colombia (Fjeldså 2004). The population in Ecuador is estimated at no more than 1,000 adult birds (T. Santander G. in litt. 2014, see also Guevara et al. 2016). The species’s population is said to have become very localised north of the Bolivian-Peruvian Altiplano, and it may be vanishing from the páramos of northern Peru, Ecuador and Colombia. Since the early 1980s, the species has undergone local extinctions and colonisations in Ecuador (T. Santander G. in litt. 2014, Guevara et al. 2016). It is no longer found below 3,000 m and has been extirpated from Yahuarcocha and San Pablo, with a decline of c.80% also noted at Cuicocha since the early 1970s. It is estimated that over 90% of the present population in Ecuador relies on just two wetland sites: La Mica and Colta. The latter site was recently colonised by the species, with extremely rapid population growth since 2004, most likely owing to immigration (Guevara et al. 2016). This event coincides with drastic population declines on Lake Mica since the construction of a dam in the early 1990s (Fjeldså 2004, T. Santander G. in litt. 2014), but the population there has remained stable since 2004 (T. Santander G. in litt. 2014, Guevara et al. 2016).

Ecology

This species inhabits open wetlands, showing a preference for weakly alkaline lakes, and requires extensive shallow areas with abundant macro-zooplantkton or submergent vegetation with abundant aquatic insects and amphipods (Fjeldså 2004). It breeds in colonies, mainly in areas with reedbeds (Fjeldså 2004).

Threats

Threatening processes include the modification, pollution and siltation of wetlands, as well as the potential impacts of introduced species (Fjeldså 2004). In Colombia, the species is in decline owing to habitat loss, introduced trouts Oncorhynchus mykiss and hunting (Renjifo et al. 2016). In Ecuador, the population on Lake Mica appears to have been heavily impacted by the construction of a dam in the early 1990s, while the growing population at Colta is threatened by an accelerated sedimentation process (T. Santander G. in litt. 2014).

Conservation actions

Conservation Actions Underway
Some local initiatives exist for protecting breeding sites in Ecuador (Fjeldså 2004).

Conservation Actions Proposed
Carry out coordinated surveys to assess the total population size and overall trend. Investigate the impacts of introduced species. Increase the area of suitable habitat that is protected.

Acknowledgements

Text account compilers
Hermes, C.

Contributors
Butchart, S., Ekstrom, J., Santander, T., Symes, A. & Taylor, J.


Recommended citation
BirdLife International (2024) Species factsheet: Northern Silvery Grebe Podiceps juninensis. Downloaded from https://datazone.birdlife.org/species/factsheet/northern-silvery-grebe-podiceps-juninensis on 22/12/2024.
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 22/12/2024.