Altogether, 388 species of apparently wild state or released species which have established self-supporting breeding populations in Estonia or in neighbouring countries (i.e. categories A-C) have been recorded in Estonia by 31.03.2018.
Categories
A - Species and subspecies that have been recorded in an apparently natural state only before 1950.
B - Species and subspecies that have been recorded in an apparently natural state only before 1950.
C - Released or escaped species and subspecies that have established a self-supporting breeding population in the own country, also birds coming from category C population of another country.
D - Species and subspecies that would otherwise appear in categories A or B except that there is reasonable doubt that they have ever ocurred in a natural state.
E - Escapees from captivity.