The varied geography of this area gives rise to numerous different habitats. It is the stomping ground of a significant variety of reptiles, amphibians, mammals and fish, most of which are protected under national and European legislation. Previously, Lake Karla had great fish populations. The species found in the lake today is the carp, the Tsironas and butterfly, and there are efforts to regenerate the area. Not far off, the Polydendri forest is rife with wildlife, including the wildcat lynx, wolf, deer, hare, wild boar, etc.
According to the Management Body of the Eco-development Area of Karla-Mavrovouni-Kefalovrisi-Velestino there is a list of mammals, amphibians and reptiles in the area, mentioning some of the threats that they face:
· Wild boar (Sus scrofa): on the increase in the area, causing a bit of trouble for farmers, especially in the corn fields.
· European badger (Meles meles): roams around the foothills of Mavrovouni and Karantao, and is often in danger as it tries to cross the Volos-Larissa national road. Crossings under this highway would help preserve the badger and many other animals.
· European roe deer (Capreolus capreolus): permanent resident of the eastern part of Mavrovouni including oak and beech forests, as well as the dense holm oak forests. A ban on hunting in the area has helped maintain a number of these animals but more can be done.
· Beech Marten (Martes foina): a nocturnal creature yet travels also during the day. It is found all over the mountain and near animal farms around the Lake Karla area.
· Grey Wolf (Canis lupus): can be found in the area, and a ban on hunting has helped increase populations nationwide. There are about 2 or 3 lone wolves in the area and no evidence of a herd.
· European hare or brown hare: lives in the shrublands and grasslands within the dense forests of Mount Mavrovouni and some other high areas in the region.
· Red squirrel (Sciurus vulgaris): thrives in Mavrovouni in large numbers, feeding on wild fruit and nuts from trees, hampering the production of nuts and chestnuts. It is often hunted by farmers, requiring better measures to protect crops and prevent the unnecessary killing of these animals.
· Red fox (Vulpes vulpes): thriving in the region thanks to the presence of rodents and birds around Lake Karla. However it too is a victim of the Old National Road (Volos-Lamia), implying a need for better management measures.
· Wildcat (Felis silvestris): roams around the plains of the Lake Karla region, particularly around the shallow parts of the lake where it finds much food.
· Yellow-bellied toad (Bombina variegate): spends much time around the shallow areas of the lake, almost always near the water. The back is generally very dark but can change color according to its environment, while the tummy area ranges from a bright orange to pale yellow depending on the subspecies. You may see gray or dark spots on the belly, or it could be completely yellow.
· European tree frog (Hyla arborea): a small green frog that prefers wet areas with dense vegetation.
· Fire salamander (Salamandra salamandra) loves damp places and holes mainly in flowing streams on the eastern part of Mount Mavrovouni.
· European green toad (Bufo viridis): mainly a nocturnal toad, green in color, and likes drier places.
· European pond turtle (Emys orbicularis): one of two species of freshwater turtles that has spread to Greece and prefers water with a slow flow. It is protected under national and EU regulations.
· Hermann's tortoise (Testudo hermanni): a land turtle belonging to the family of Testudinidae with 40 species. Herbivorous slow-moving turtle that can live in dry habitats, common in the Lake Karla region.
· Horned viper or sand viper (Vipera ammodytes): considered the most poisonous viper in Europe because of its large size, long teeth (up to 13 mm) and highly toxic venom. Found primarily in the southern and western parts of Mount Mavrovouni and in plains with more rodents. Protected at national and EU level, it is under threat due to human pressures and loss of habitat, as well as use of drugs to kill mice in the fields.
· Grass snake or water snake (Natrix natrix): A non-poisonous snake with a great variety of colors and designs. Bathes very skillfully and quickly, often found near water and feeds almost exclusively on amphibians. While it prefers wetlands it can thrive well away from it.
· European green lizard (Lacerta viridis): Could be of one color or with light colored stripes along the spine. This big, fast and agile lizard prefers sunny spots with shrubs, where it can hide. It feeds mainly on invertebrates and occasionally on vertebrates and fruits.
· European blind snake (Typhlops Vermicularis): reaches up to 40 cm in length but normally less than 30 cm, it has adapted well to life underground. Eats ants, termites, small arachnids and larvae among other small invertebrates. Located in Mavrovouni and North Pelion.
· Glass lizard (Ophisaurus apodus): Europe's largest lizard with a total body length reaching 140 cm and the tail not clearly separated from the body. This legless lizard is protected under national and EU legislation. Heavily threatened as people think they're snakes and kill them all the time.
· Balkan whip snake (Coluber gemonensis): a harmless snake and the longest in Greece. It feeds on rodents and insects. It shouldn't be killed, just left alone to go on its way.
· Balkan wall lizard (Podarcis taurica): prefers open areas such as pastures, fields, olive groves, gardens, sparsely vegetated dunes and sometimes open scrub. Threatened by habitat loss through intense agricultural activity and use of agrochemicals. Protected by national and EU legislation, and is common in the region.