About the Habitat

Habitat 9180* Tilio-Acerion forests of slopes, screes and ravines is made up of mixed, broadleaf forests, which must include maple, linden and ash. The habitat is usually located on steep and vertical rocky slopes or ravines. In Europe, forests of this type grow on silicate rock. In Bulgaria they are usually on limestone. Two habitat subtypes can be distinguished, depending on the tree species, humidity, inclination, exposure and bedrock:

  1. Forests on wet screes and ravines – in shady areas vegetation with higher soil humidity preferences grows. This includes Balkan maple, maple, European ash, Scotch elm, Heldreich’s maple, etc. The herbaceous layer in these areas contains ramsons, cleavers, Herb-Robert, wood avens, hart’s-tongue, common nettle, etc.
  2. Forests on dry screes and ravines – dry and heat loving forest vegetation grows on sunny screes. Trees, such as small-leaved and silver linden, European hornbeam, common hazel, different oak species and grasses like snowdrop anemone, cowslip, corydalis, sesleria, etc. are present.

The habitat is home to threatened and protected plant species, like the Balkan maple,
Balkan fescue, Orpheus flower, European yew; fungi: tiered tooth fungus; birds: middle spotted woodpecker, European green woodpecker, grey-headed woodpecker, Eurasian treecreeper, Eurasian nuthatch, lesser spotted eagle, Levant sparrowhawk, booted eagle, Eurasian wryneck, black stork; bats: barbastelle, serotine bat, lesser mouse-eared bat, greater horseshoe bat, common pipistrelle, Savi’s pipistrelle, etc.


The Tilio-Acerion forests of slopes, screes and ravines are distributed throughout Europe. The center of this habitat’s distribution is continental Europe. In Bulgaria, the habitat is distributed in the Balkan, Rhodope, Rila, Vitosha, Osogovo and Lozenska mountains at 800 to 1400 m a.s.l.

The project will work in habitat 9180* in the Central Balkan Natura 2000 site, which overlaps with Central Balkan National Park. The project actions will be performed in both habitat subtypes.

Distribution map

See the map of the distribution of the habitat, according to The Red Data Book of the Republic of Bulgaria


The overall conservation status of the habitat in European Union member countries, including Bulgaria, is unfavourable-unsatisfactory or unfavourable-bad. This is why habitat 9180* is of high conservational priority in the European Ecological Network Natura 2000. It is included in the annexes of the Habitat Directive and the Bern Convention. In Bulgaria it is protected by the Biological Diversity Act. It is included in the “Threatened” category of the Red Data Book of the Republic of Bulgaria.

In Bulgaria, habitat 9180* is highly fragmented and and its distribution is localised. This is due to the natural change in the species composition (Ecological succession), but also, to human activity – unregulated and/or improperly planned felling, fires, building of power lines and roads, air pollution.

Climate change is adversely affecting Tilio-Acerion forests on wet screes and ravines. They are sensitive to the diminishing air humidity and suffer due to the dry conditions.

Project Actions

Actions, envisioned in the Management Plan of Central Balkan National Park (2016 – 2025) will be executed as part of the project.

The measures for the improvement of the conservation status of the habitat, which we will be executing and demonstrating, correspond to one of the main long-term goals of the Management Plan “To conserve the natural status of forest ecosystems and, especially, of natural forests” and include:

See presentation (in Bulgarian) about the activities in 2018 and 2019 for improvement of the status of habitat 9180*.

Monitoring is being executed as part of the project

The features under observation are:  species composition and age of the tree layer, made up of different maple species, European ash, Scotch elm, small-leaved linden, Norway maple, etc.; introduction and spread of invasive alien species; quantity of deadwood; rare and threatened animal and plant species, dwelling in the habitat; the effect of the actions on the knowledge, attitudes and behaviour of the interested parties, toward habitat 9180*; the influence of project actions on the wellbeing of people and nature is being also observed.

Lowland hay meadows

Semi-natural Dry Grasslands and Scrubland Facies: on Calcareous Substrates

Endemic forests with Juniperus spp.