Rock Ptarmigan Lagopus muta


Justification of Red List Category
This species has an extremely large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). Despite the fact that the population trend appears to be decreasing, the decline is not believed to be sufficiently rapid to approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size is extremely large, and hence does not approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.

Population justification
The global population is estimated to number > c.8,000,000 individuals (Rich et al. 2004). The European population is estimated at 257,000-1,010,000 pairs, which equates to 514,000-2,020,000 mature individuals (BirdLife International 2015). Europe forms approximately 10% of the global range, so a very preliminary estimate of the global population size is 5,140,000-20,200,000 mature individuals, although further validation of this estimate is needed. National population estimates include: <c.100 breeding pairs in China; c.100-10,000 breeding pairs in Japan and c.100,000-1 million breeding pairs in Russia (Brazil 2009).

Trend justification
The population has declined locally owing to habitat loss (especially over-grazing by sheep) and mountain tourism, including establishment of ski-resorts. The species is not thought to be vulnerable to over-hunting (del Hoyo et al. 1994). In Europe the population size is estimated to be decreasing at a rate approaching 30% in 12.6 years (three generations) (BirdLife International 2015).


The species inhabits rocky tundra with fairly sparse vegetation or alpine summits. It is rarely found in areas of high shrubs or below the tree line. During winter it lives in less snowy regions or uses windswept ridges and slopes due to its dependence on ground vegetation for food. Laying is generally in June, however birds in Scotland lay from late May and those in Spitsbergen from mid-June (de Juana et al. 2016). It typically lays five to eight eggs but sometimes up to twelve (Madge and McGowan 2002). The nest is a shallow depression lined with plant material and some feathers, usually in the open and sheltered by a large stone or shrub. In winter it takes food from the ground, mainly buds and twigs of species including Salix. In the Alps and other southern areas its main winter foods are berry bearing shrubs including Vaccinium and Empetrum. In spring and autumn it has a more varied diet taking leaves, flowers, berries and seeds of a wide range of plants. Most populations make limited movements, which are largely altitudinal and depend on local conditions and weather (de Juana et al. 2016).


The species faces some pressures at a local scale, such as habitat degradation and over-hunting (Madge and McGowan 2002). It is particularly susceptible to over-harvesting in the spring. Most habitat loss occurs due to the development of tourist facilities such as ski facilities and collision with cables around ski stations can cause mortality. Human presence may cause disturbance and displace birds from their wintering habitat. It is thought that, in Sweden, overgrazing from reindeer is causing declines (Storch 2007). A recent decrease detected in the Swiss Alps, of 30% in a decade was attributed to climatic change (de Juana et al. 2016). Climatic warming in the Arctic has resulted in a rapid expansion of woody shrubs over the past half century which may result in habitat loss for the species (de Juana et al. 2016).

Conservation actions

Conservation Actions Underway
EU Birds Directive Annex I and II. In most of its European range, the only management is the setting of hunting seasons and bag limits and in Europe it is only protected in a few countries. A small proportion of its range is covered by protective areas, although these are considered to only have a low role in species survival except in those countries at the edge of the range (e.g., Andorra, France, Spain). Most monitoring is limited to the local scale. In Germany a programme to limit human disturbance by ski-touring has been initiated and in Iceland research into the effects of hunting there is ongoing (Storch 2007).

Conservation Actions Proposed
Monitoring of populations in areas with potentially high hunting pressures should be undertaken to ensure they are sustainable. Measures should be taken in mountain ranges with high tourism to minimise the spatial and temporal overlap between important habitats and recreational activities and their effectiveness monitored. Also, actions to minimize the numbers of generalist predators in these areas should be taken. Research into the impacts of hunting and habitat alteration on population dynamics should be undertaken. More understanding of its migration and dispersal behaviour and the survival of young birds over winter is needed (Storch 2007).


Text account compilers
Ekstrom, J., Ashpole, J, Butchart, S.

Recommended citation
BirdLife International (2022) Species factsheet: Lagopus muta. Downloaded from on 08/12/2022. Recommended citation for factsheets for more than one species: BirdLife International (2022) IUCN Red List for birds. Downloaded from on 08/12/2022.