Due to a large number of diverse habitats, the animal life of the protected areas of the Šibenik-Knin County is uncommonly rich, with numerous endangered, rare but also unusual animal species living in the protected areas of the County.
The waters of the Šibenik-Knin County are home to a resident population of common bottlenose dolphins (Tursiops truncates), with about 50 individuals. The loggerhead sea turtle (Caretta caretta) is a marine reptile that inhabits this portion of the Adriatic as well as the red coral (Corallium rubrum) the fan mussel (Pinna nobilis), and the violescent sea-whip (Paramuricea clavata). There are numerous taxa of fish and shellfish, especially in the areas where fresh water and salt water meet (the lower course of the Krka River and the Channel – Port area).
A wider area of the Šibenik-Knin County is inhabited or is possibly inhabited by some endangered and strictly protected bird species, with the most famous and most endangered species among them being the lanner falcon (Falco biarmicus), the Bonelli’s eagle (Hieraaetus fasciatus), the pygmy cormorant (Phalacrocorax pygmaeus) and the glossy ibis (Plegadis falcinellus) as well as some nesting populations at risk such as the peregrine falcon (Falco peregrinus), the European honey buzzard (Pernis apivorus), the short-toed snake eagle (Circaetus gallicus), the common sandpiper (Actitis hypoleucos) and the purple heron (Ardea purpurea).
This whole area is inhabited by bats, which can be found in the lower reaches of the Krka River throughout the year. The following are endangered species that can be found there: Mehely’s horseshoe bat (Rhinolophus mehelyi), the long-fingered bat (Myotis capaccinii), the common bent-wing bat (Minopterus schreibersii), Blasius’s horseshoe bat (Rhinolophus blasii), Bechstein’s bat (Myotis bechsteinii), the greater horseshoe bat (Rhinolophus ferrumequinum), the lesser horseshoe bat (Rhinolophus hipposideros) and Geoffroy’s bat (Myotis emarginatus).
It is worth noting that the Šibenik-Knin County provides a habitat for three large wild animals, i.e. the wolf and the lynx (strictly protected species) and the bear (protected species). The underground karst fauna of the Krčić River includes some endemic amphibian species such as the olm (Proteus anguinus cf. anguinus). Some endangered reptiles are also rare – the European pond turtle (Emys orbicularis I.), which inhabits the area along the Krka River, and Hermann’s tortoise (Testudo hermanni), which can be found in the grassy rocky valleys. The karst viper (Vipera ursinii macrops) belongs to endangered species of snake inhabiting the hill, submontane and mountain pastures of the karst mountains above 1000 metres (Dinara Mountain).
There are butterfly communities that are also at risk due to lack of mowing and grazing caused by severe depopulation – the Dalmatian ringlet (Proterebia afra dalmata), a community of butterflies inhabiting only the grassland of Central Dalmatia (Suho polje near Knin), and the mountain alcon blue (Maculinea rebeli), with its habitat on the dry meadows of the mountain area.
Two freshwater fish species, exclusively endemic to Croatia (steno-endemic species) –Tursky dace (Telestes turskyi), which is a critically endangered species, and a species of ray-finned fish Phoxinellus dalmaticus are found only along the rivers of Krka and Čikola. The ukliva dace (Telestes ukliva) is a critically endangered species living in the cold waters of the source of the Cetina River as well as the Dalmatian spined loach (Cobitis dalmatina), which is endemic to the Adriatic basin and Croatia.
Fauna of the significant landscape Channel – Port
The mouth of the Krka River is inhabited by 56 species of shellfish. Mussel (Mytilus galloprovincialis) and oyster (Ostrea edulis) populations are abundant, and have been under controlled breeding for the past 25 years. Among the abundant Bivalves are the warty venus (Venus verrucosa), Noah’s arc (Arca noae) and cross-cut carpet shell (Tapes decussatus), while rare bivalves are the wing oyster (Pteria hirundo), dog cockle (Glycymeris glycymeris), European thorny oyster (Spondylus gaederopus) and heart cockle (Glossus humanus). Among the protected bivalves are the date shells (Lithophaga lithophaga) and noble pen shell (Pinna nobilis). Shapes and colours abound with the variegated scallop (Chlamys varia), queen scallop (Aequipecten opercularis), while Chlamys pesfelis and the scallop (Pecten jacobaeus) have beautiful shapes.
The river mouth is known for its large schools of thinlip grey mullet (Liza ramada) and thicklip grey mullet (Chelon labrosus). Fish species important in the traditional fishing are the European seabass (Dicentrarchus labrax), common dentex (Dentex dentex), striped seabream (Lithognathus mormyrus), common pandora (Pagellus erythrinus), eel (Anguilla anguilla) and European conger (Conger conger), while the pink dentex (Dentex gibbosus) represents the distinctness of this area.
Fauna of the significant landscape Čikola River and Canyon
The Čikola River canyon is inhabited by four amphibian species that are listed in the Red Book of Amphibians and Reptiles of Croatia: common toad (Bufo bufo), green toad (Bufo viridis), marsh frog (Rana ridibunda) and agile frog (Rana dalmatina). Nine of the reptile species found here have been included in the Red Book of Amphibians and Reptiles of Croatia, of which four are lizards: Balkan green lizard (Lacerta trilineata), sharp-snouted rock lizard (Dalmatolacerta oxycephala), a relict and endemic to the southwestern Dinarids, Italian wall lizard (Podarcis sicula) and Dalmatian wall lizard (Podarcis melisellensis), an endemic of the eastern coast of the Adriatic Sea, and five are snakes: Dahl’s whip snake (Platyceps najadum), four-lined snake (Elaphe quatuorlineata), cat snake (Telescopus fallax), grass snake (Natrix natrix) and dice snake (Natrix tessellata).
Thanks to the truly primal nature still preserved here, the canyon is home to 22 mammal species. The majority of these, 13 species, are bats, of which nine are listed in the Red Book of Mammals of Croatia: greater horseshoe bat (Rhinolophus ferrumeguinum), Mediterranean horseshoe bat (Rhinolophus euryale), Blasius’ horseshoe bat (Rhinolophus blasii), lesser horseshoe bat (Rhinolophus hipposideros), common bent-wing bat (Miniopterus schreibersii), Bechstein’s bat (Myotis bechsteinii), long-fingered bat (Myotis capaccinii), Geoffrey’s bat (Myotis emarginatus) and greater mouse-eared bat (Myotis myotis).
Some twenty animals were identified at Topla peć cave, the longest cave in the Čikola Canyon and an exceptional subterranean habitat. There have been frequent finds of the subtroglophile snail Oxychilus (Oxychilus) cellarius and, the Croatian endemic troglobite pseudoscorpions Chthonius (Globochthonius simplex ) and Microchthonius rogatus, the centipede Scutigeria coleoptrata, the cave cricket Troglophilus cavicola and the moth Apopestes spectrum in winter. Topla peć is a key habitat to two types of bat: Blasius’ horseshoe bat and the lesser horseshoe bat.
Fauna of the significant landscape Žut-Sit Archipelago
The terrestrial fauna of the Žut-Sit archipelago has not been systematically studied; most data are outdated and are based primarily on verbal reports. Among the amphibians on the islands, the European green toad (Bufo viridis) has been included in the Red Book of Amphibians and Reptiles of Croatia, while among the reptiles, the four-lined snake (Elaphe quatuorlineata) and Hermann’s tortoise (Testudo hermanni), are included in the same Red Book in the category of near threatened species. About twenty bird species are known to inhabit the islands, including the tawny pipit (Anthus campestris), included in the Red Book of Threatened Birds of Croatia in the category of least concern, and the Peregrine falcon (Falco peregrinus) in the category of vulnerable species. The common bent-wing bat (Miniopterus schreibersii) has been included in the Red Book of Mammals of Croatia in the category of endangered species.
Sea grass (Posidonia oceanica) meadows are common in the sea surrounding the islands. The sea is habitat for about a hundred fish species, seven of which have been included in the Red Book of Marine Fish of Croatia. The category of endangered species includes the dusky grouper (Epinephelus marginatus), that is found along the underwater reefs on the craggy sea bottom. The category of vulnerable species includes the red porgy (Pagrus pagrus), a benthic-pelagic fish found above rocky substrates and coralligenous bottoms, the long-snouted seahorse (Hippocampus guttulatus), a demersal, coastal, sedentary fish that inhabits the sea grass meadows, and the green wrasse (Labrus viridis), a coastal benthopelagic fish species that lives along the rocky coastal areas and in sea grass meadows. The category of near threatened species includes the brown meagre (Sciaena umbra), a coastal fish on overgrown rock and rocky-sand sea beds and the shi drum (Umbrina cirrosa), a demersal fish found over rocky/sandy and rocky/silty sea beds. Tuna (Thunnus thynnus), a pelagic fish that occasionally approaches the coast, is in the category of data deficient species. The seas around Žut Island are home to the loggerhead turtle (Caretta caretta), which is included in the Red Book of Amphibians and Reptiles of Croatia in the category of endangered species, while the bottlenose dolphin (Tursiops truncatus), a marine mammal, is included in the Red Book of Mammals of Croatia in the category of endangered species.
Fauna of the significant landscape Gvozdenovo – Kamenar
The fauna of this area has not been systematically studied, but it is known that the thickets and gariggues are habitat for Hermann’s tortoise (Testudo hermanni), which is included in the Red Book of Amphibians and Reptiles of Croatia in the category of near threatened species, and the slow worm (Anguis fragilis), a protected native species. The pine woods are home to the red squirrel (Sciurus vulgaris), which is included in the Red Book of Mammals of Croatia in the category of near threatened species.
Fauna of the significant landscape Krka River – lower course
A total of 45 shellfish species are found in Prukljan Lake. Species that are common on the silty/sandy substrate are: warty venus (Venus verrucosa), carpet shell (Tapes decussatus) and lagoon cockle (Cerastoderma glaucum), distributed virtually to the base of Skradinski buk. On the rocks we find the blue mussel (Mytilus galloprovincialis), oyster (Ostrea edulis) and Noah’s arc (Arca noae). Shapes and colours abound with the variegated scallop (Chlamys varia), queen scallop (Aequipecten opercularis) and scallop (Pecten jacobaeus). Among the protected shellfish, the date shell (Lithophaga lithophaga) is found in the hollows of the limestone rocks. Large schools of thinlip grey mullet (Liza ramada) and small schools of thicklip grey mullet (Chelon labrosus) are found in Prukljan Lake. Numerous commercially important fish species are found over rocky substrates, including the European seabass (Dicentrarchus labrax), common dentex (Dentex dentex), striped seabream (Lithognathus mormyrus), common pandora (Pagellus erythrinus) and European conger (Conger conger), while the pink dentex (Dentex gibbosus) represents the distinctness of this area. Eels (Anguilla anguilla) and various gobies (Gobiidae) are common on the sandy substrates.
The wetland meadows of Pruljkan and the reeds of the mouth of the Guduča River abound in amphibians, while the rocky terrain with sparse low vegetation has a rich reptile fauna. The grass snake (Natrix natrix) and dice snake (Natrix tessellata) inhabit the Guduča River and the wetland meadows around its mouth, while the nose-horned viper (Vipera ammodytes) is found in the thickets and rocky terrain. The European legless lizard (Ophisaurus apodus) inhabits the garrigues and thickets, the endemic Dalmatian algyroides can be found on the old dry stone walls, while the Balkan green lizard (Lacerta trilineata) inhabits the rocky terrain. A total of 153 bird species have been observed on Prukljan Lake and the mouth of the Guduča River, including 61 nesting species, 56 migratory species and 50 wintering species. Common species include Eurasian coot (Fulica atra), little grebe (Tachybaptus ruficollis), great crested grebe (Podiceps cristatus), tufted duck (Aythya fuligula), Caspian gull (Larus cachinnans) and black-headed gull (Larus ridibundus). Rare birds include the Eurasian bittern (Botaurus stellaris) and calandra lark (Melanocorypha calandra), while the threatened birds are the pygmy cormorant (Haliaetor pygmaeus), great egret (Egretta alba), lanner and Peregrine falcons (Falco biarmicus and F. peregrinus) and short-toed snake eagle (Circaetus gallicus). During the autumn migration, large flocks of European bee-eater (Merops apiaster) can be seen here.
Tradanj cave is situated in St. Joseph’s Channel, on the right bank of the Krka River. The cave fauna includes scorpions of the genus Euscorpius, spiders of the genera Troglohyphantes and Tegenaria, the pseudoscorpions Chthonius litoralis, endemic to Dalmatia, and Pselaphocernes litoralis, and the house centipede Scutigeria coleoptrata. Bats are present year round, with up to 20,000 individuals of five species forming nursing colonies for mothers and young every year:. Mediterranean horseshoe bat (Rhinolophus euryale), greater horseshoe bat (Rhinolophus ferrumequinum), Geoffrey’s bat (Myotis emarginatus), lesser mouse-eared bat (Myotis blythii) and long-fingered bat (Myotis capaccinii). Downstream, just opposite the southern entrance to St. Joseph’s Channel is a pit on the northern slopes of the Orljak hill, 20 m above the Krka River. This is a branching speleological structure whose bottom reaches the Krka river level and sea level, with a total length of 90 m and depth of 23 m. At the bottom of the pit is a brackish lake (anhihaline pit). The cave is home to the tubeworm Ficopomatus enigmaticus, the amphipod Niphargus salonitanus, endemic to the Dinarids (in both fresh and brackish water), and freshwater shrimp of the genus Troglocaris.
Fauna of the significant landscape Krka River – upper course
The complete darkness of the Krka spring is habitat for the endemic isopod Monolistra hercegoviniensis brevipes and the stigobiontic crustacean Spelaeocaris pretneri, both endemic to the Dinaric area, and distributed from Herzegovina to Lika.
Four species of fish inhabiting the Upper Krka River have been included in the Red Book of Freshwater Fish of Croatia: soft-muzzled trout (Salmothymus obtusirostris krkensis), a Croatian endemic in the category of critically endangered species; sea trout (Salmo faroides) in the category of endangered species; and Illyric dace (Squalius illyricus), an endemic of the Adriatic basin and the Zrmanja dace (Squalius zrmanjae), a Croatian endemic, in the category of vulnerable species. The alien rainbow trout (Oncorhynchus mykiss) is a common species, with its controlled farming taking place near the source of the Krka River. The Upper Krka River is a habitat for the otter (Lutra lutra), a species endangered at the European scale.