With its variety of brackish and freshwater habitats, Škocjanski zatok Nature Reserve is a heaven not only for wildlife, but also for all those who like to observe and enjoy nature. The area is particularly interesting because of its high bird diversity. Since 2001 a total of 259 different bird species have been recorded on this protected area’s 122,7 hectares. Different species occur at certain times of year and in varying numbers. Some species are breeding birds, others are winter visitors, while some only stop-over here for a short time during migration. Breeding birds have a higher conservation value and are therefore the most interesting group. Up to 48 species of breeding birds have been recorded at the reserve so far, although the exact number varies from year to year. The brackish lagoon is an important habitat for the breeding of Common (Sterna hirundo) and Little Terns (Sternula albifrons) which form mixed colonies on the muddy islands. Other birds nesting in the same habitat in good numbers include Black-winged Stilt (Himantopus himantopus), Common Redshank (Tringa totanus) and Little Ringed Plover (Charadrius dubius). The rare Kentish Plover (Charadrius alexandrinus) has recently re-colonised the lagoon after a decade-long absence, while the Avocet (Recurvirostra avosetta), another rare breeding bird in Slovenia, established a small nesting population in 2019.
The freshwater marsh also offers an excellent breeding habitat for several species which are rare breeders in Slovenia, such as Little Bittern (Ixobrychus minutus), Greylag Goose (Anser anser), Water Rail (Rallus aquaticus), Zitting Cisticola (Cisticola juncidis) and Purple Heron (Ardea purpurea), the latter nesting only here and nowhere else in the country. The dense reedbeds and waterside bushes are occupied by many pairs of Great Reed (Acrocephalus arundinaceus), Reed (Acrocephalus scirpaceus) and Cetti’s Warbler (Cettia cetti), while other interesting breeders of the reserve include Great Crested Grebe (Podiceps cristatus), Pochard (Aythya ferina), Turtle Dove (Streptopelia turtur), Yellow Wagtail (Motacilla flava) and Melodious Warbler (Hippolais polyglotta).
In winter the reserve hosts large numbers of waterbirds. The most prominent are small flocks of Greylag (Anser anser) and White-fronted Geese (Anser albifrons), while ducks like Wigeon (Mareca penelope), Shoveler (Spatula clypeata), Teal (Anas crecca) and Gadwall (Mareca strepera) are much more numerous. With a bit of luck, in the reedbeds it is possible to see the solitary Great Bittern (Botaurus stellaris) or small flocks of Penduline Tits (Remiz pendulinus), Reed Buntings (Emberiza schoeniclus) and even Bearded Reedlings (Panurus biarmicus). The wet meadows are a favoured feeding area of Snipe (Gallinago gallinago), Curlew (Numenius arquata) and Water Pipit (Anthus spinoletta).
As Škocjanski zatok is also an important stopover site for migratory birds, a greater diversity of species can be expected during spring and autumn migration. Common spring migrants, present in good numbers include Ruff (Calidris pugnax), Wood Sandpiper (Tringa glareola), Lapwing (Vanellus vanellus), Garganey (Spatula querquedula), Marsh Harrier (Circus aeruginosus) and Squacco Heron (Ardeola ralloides). Slightly scarcer, but regular migrants include Ferruginous Duck (Aythya nyroca), Spoonbill (Platalea leucorodia), Glossy Ibis (Plegadis falcinellus), White-winged (Chlidonias leucopterus) and Whiskered Tern (Chlidonias hybrida). In autumn Bluethroat (Luscinia svecica), Little (Zapornia parva) and Spotted Crake (Porzana porzana) can be observed feeding along the edges of the reedbeds. Among the raptors worthy of mention is the Short-toed Eagle (Circaetus gallicus) which regularly hunts over the freshwater wetland in early spring and late summer.
Several species of birds are resident on the reserve and can be observed all year-round, including Little Egret (Egretta garzetta), Great Egret (Ardea alba), Grey Heron (Ardea cinerea), Coot (Fulica atra), Mute Swan (Cygnus olor), Mallard (Anas platyrhynchos), Moorhen (Gallinula chloropus), Little Grebe (Tachybaptus ruficollis), Greenshank (Tringa nebularia), Yellow-legged Gull (Larus michahellis), Pygmy Cormorant (Microcarbo pygmaeus), Cattle Egret (Bubulcus ibis) and Kingfisher (Alcedo atthis).
Bird species in the reserve occur in different ways and at different times. We divided them into several basic groups: