Important Bird Areas (IBA) in Slovenia

IBA Kočevsko-Kolpaphoto: Mirko Perušek

In 2011, we identified 35 Important Bird Areas (IBA) in Slovenia according to BirdLife International criteria. IBA function as expert blueprints for the definition of Natura 2000 Special protected Areas, as demanded from EU members by the Birds Directive. IBA cover 27% of Slovenian territory.


IBA inventories for Slovenia have been published four times so far, in 1989 (GRIMMET & JONES 1989), 2000 (POLAK 2000), 2003 (BOŽIČ 2003) and 2011 (DENAC et al. 2011).

The 1989 inventory examined Slovenia as part of Yugoslavia, so IBA were defined by different criteria then in subsequent inventories. The 2000 inventory used only global (A) and regional (B) criteria to define IBA, since Slovenia was not yet a member of the European Union. In 2003, before joining the EU, we prepared an inventory which defined the areas on the basis of C criteria (criteria for the European Union). According to the rulings of the European Court, these present the best expert blueprints for defining Natura 2000 Special Protected Areas (SPA) in accordance with the Birds Directive (Article 4).


Much new ornithological data has accumulated since 2003, which led to a revision of IBA in 2011. The current international criteria for defining IBA were used: global (A), regional (B) and European Union (C) criteria (HEATH & EVANS 2000). We added national criteria (D) to adequately include rare species from the Birds Directive Supplement I as well as endangered migratory species. D criteria were not used for area selection but merely to add species to existent areas. Bird species with defined areas are referred to as qualifying.


The 2011 IBA revision identified 35 areas measuring a total of 5538.1 km2. In comparison with the 2003 IBA, the area was increased by 702,7 km2, including Trnovski gozd, declared as SPA in 2004 by the Decree on Special Protection Areas, but still lacking the IBA status. We defined nine new areas: Črete, Debeli rtič, Gluha loza, Karavanke, Renški glinokopi, Spodnja Sava, Srednja Sava, Strunjan and Trnovski gozd. IBA Kozjansko-Jovsi from 2003 was divided into two areas, Kozjansko and Dobrava-Jovsi.


The 2013 Decree on Special Protection Areas (Natura 2000 areas) confirmed approximately 90% of IBA as SPA (Official Gazette of the Republic of Slovenia, No. 33/2013). In these areas, a favourable conservation state of the qualifying bird species must be maintained, and the impacts of each potentially threatening intervention assessed. A Natura 2000 areas management programme which takes into account the ecological requirements of the qualifying bird species is currently being prepared.


Katarina Denac (


Strokovni predlog za revizijo posebnih območij varstva (SPA) z uporabo najnovejših kriterijev za določitev mednarodno pomembnih območij za ptice (IBA). Končno poročilo (dopolnjena verzija).
DOPPS, Ljubljana.

BOŽIČ, L. (2003):
Mednarodno pomembna območja za ptice v Sloveniji 2. Predlogi Posebnih zaščitenih območij (SPA) v Sloveniji. Monografija DOPPS št. 2.
DOPPS, Ljubljana.

HEATH, M. F. & EVANS, M. I. (ur.) (2000):
Important Bird Areas in Europe. Priority sites for conservation. 2 vol. BirdLife Conservation Series No 8.
Cambridge, UK.

POLAK, S. (ur.) (2000):
Mednarodno pomembna območja za ptice v Sloveniji. Important Bird Areas (IBA) in Slovenia. Monografija DOPPS št. 1. (1. del, 2. del)
DOPPS, Ljubljana.

GRIMMET, R. F. A. & JONES, T. A. (1989):
Important Bird Areas in Europe. ICBP Technical publication No. 9.
International Council for Bird Preservation, Cambridge, UK.