The fauna of an area is related to form of vegetation. Animals select areas where they can easily find food and water and. At the same time an area must provide safety, so they can create their nest and reproduce. In the area it have been recorded 225 animal species and many of them are under the threat of vanishing and protected by Greek and European laws and international conventions.
The coastal animals found in Strymonikos and Ierissos gulf can be distinct into five categories:
- Mammal: Seventeen species have been recorded in the area. Some of them like hedgehog (Erinaceus concolor), weasel (Mustela nivalis), otter (Lutra lutra) and wildcat (Felis silvestris) have been characterized as threaten and are protected by relative laws.
- Avifauna: A hundred and sixty four species of birds have been recorded in the area, at least 88 of which nesting here, while the rest either spend the winter here or pass through the area during their migration. 23 of these species are living in water, 20 are predatory, 12 are sea birds and 87 are kinds of sparrow.
- Reptiles: Eighteen species have been recorded in the area; all of them are under the threat of vanishing and are protected by relative laws. Starting from the turtle's family, the most common one is the Mediterranean turtle (Testudo hermanni). The green lizard (Lacerta trilineata) and the emerald lizard (Lacerta viridis) can been found in the whole area under arborescent of bushy vegetation. From the family of snakes, the most common specie is the so-called sapitis (Malpolon monspessulanus).
- Amphibian: Eight amphibian species are found here to areas near to water and most of them are under the threat of vanishing. Between them is salamander (Salamandra salamandra) and frog (Rana balcanica) the most common specie of the area.
- Lake fish: Into the flowing water of the area live eighteen fish species, such as Briana (Barbus plebejus), Thrakovelonitsa (Gobitis taenia) and Perch (Perca fluviatillis). The law protects six of that species.
The fauna of the oceans and seas comprises a vast variety of species which, in adapting to their specific microenvironment (surface or deep water, rocky or sandy bottom, exposure to winds, etc.), have developed in ways, which in some cases are quite striking (e.g. vivid colors, unusual shapes, etc.).
In the coastal zone of Strymonikos and Ierissos Gulfs there are large numbers of both pelagic and benthic species:
- Most pelagic species are zooplankton (copepods, jellyfish, etc.), fishes or mammals. Thirteen species of pelagic fish have been recorded in this area, some of which are of considerable commercial value (anchovies, sardines, etc.). Mammals include the Mediterranean seal (Monachus monachus) and three species of dolphins. Porpoises, a rare species of small dolphin that is protected worldwide, have also been observed.
- The zoobenthos includes a particularly large number of species (some 560), including fishes (soles, red mullet, lanternfish), sponges (both commercial and non-commercial species), coelenterates (anemones, corals), polychaetes (worms), mollusks (ml1ssels, octopi, cuttlefish), crustaceans (crabs, shrimp) and echinoderms (starfish, sea urchins).