T he aquatorium of western Istria is an area stretching from the town of Vrsar to Cape St. Stipan below Šišan. The area of 76 000 ha almost entirely represents the marine part of the west coast of Istria and, according to the Habitats Directive, two types of habitats and one marine mammal species are classified as priorities. The sandbanks which are slightly covered by sea water all the time and submerged or partially submerged sea caves are priority habitats, and the bottlenose dolphin (Tursiops truncatus) is a priority species. The first type of habitat is characterised by high biodiversity, where the surface layer hides a number of bivalve shellfish, polychaete worms, sponges, amphipods, sea urchins, starfish, as well as seagrass Cymodocea nodosa.
Certain subtypes of this habitat are rich in fish stock and represent important fishing areas. Unfortunately, these areas are often used as beaches and are under intense human impact, especially in the summer when the risk of contamination increases. Due to its karst nature, the second type of habitat prevails along the Croatian coast.
The main characteristic of marine caves is a sharp reduction in the amount of light, so that the marine life communities found there are significantly different from other habitats. Due to the smaller amount of light, there is a small number of algae, and in the complete darkness of caves we can find only sponges, bryozoans, crabs and similar organisms for whose survival light is not a necessary factor.
A cave has been found in the underwater world of Kamenjak, in the area of the Kolombarica Cove, which can be accessed only by diving. In addition to its important biological role, it also represents a very attractive diving location for all who choose to explore it.
B ottlenose dolphin is a mammal species classified as one of the priority species to be protected through the Natura 2000 sites. The aquatorium of western Istria is one of the six important sites for the growth, development and reproduction of bottlenose dolphins in Croatia. Since their population is affected by pollution, incidental catches in fishing nets, deliberate killings, habitat degradation and noise, they are endangered and it is important to protect them in order to continue the growth of their population.
The Public Institution of Kamenjak in cooperation with the Blue World Institute conducted a survey on the numbers of bottlenose dolphins in the south of Istria, and the results show that there are 215 such specimens in the waters of western Istria.
Apart from protecting the species itself, it is precisely through the protection of habitats through the Natura 2000 sites that we can significantly contribute to the preservation of this species and allow future generations to enjoy the beautiful scenery provided by these charming and intelligent beings.
Due to its location, Kamenjak is extremely important for a large number of birds. This peninsula, looking like a finger immersed in the sea, provides them with a place to rest during flybys, with a source of food, shelter, and a place to nest and spend their winter.
The aquatorium of western Istria, the area of the Natura 2000 environmental network significant for bird preservation, is partly located within the Medulin Municipality. The target species are common kingfisher (Alcedo athis), black-throated diver (Gavia arctica), red-throated diver (Gavia stellata), shag (Phalacrocorax aristotelis desmarestii), common tern (Sterna hirundo) and sandwich tern (Sterna sandvicensis). In order to preserve these bird species it is necessary to preserve the habitats suitable for wintering and maintaining nesting populations, and the areas managed by the Institution thrive with such habitats.
The coastline, rocky islets, scented Mediterranean garrigue and grasslands are environmentally valuable areas and as such we have to maintain them in favourable condition so as to preserve birds, in particular, the 152 species found in the area of Kamenjak.