An assessment of the socio-ecological system of the Nature Park “Numto” in West Siberia was carried out based on ecosystem services (ES) mapping, applying a “cascade approach” which was modified according to the specific conditions of low commercial land-use by Indigenous Peoples and adopted with a focus on making it practicable and understandable by decision-makers. The ES values were defined through stakeholder analysis, while the mapping was based on the biophysical traits of the ecosystems and related spatial distribution of ecosystem functions. The mapped ecosystem values differ from the perceived ones. The assessment identified conflicting land uses and groups of stakeholders, including Indigenous Peoples vulnerable to future climate change-induced deficits in access to ES. The ES that are important for climate change mitigation and adaptation are not valued highly by Indigenous Peoples. ES mapping is suggested as an appropriate method for the development of straightforward recommendations for Nature Park management.