Introduction
Eurasian lynx belongs to carnivores (Carnivora ) and is one of three representative from Felidae family in Poland (two other species are: domestic cat (Felis catus) and wildcat (Felis silvestris) ) and also the largest among the Lynx genus (Garbarczyk et al. 2010). The presence of the lynx in its environment, places it at the top of the food chain. It has very strong, wide paws (Sumiński 1973; Okarma et al. 2004). The trail of tropes is called lacing (Jędrzejewski et al. 2011). The most developed of all five sences are hearing and sight. Distinctive ears are finished with 4 cm tufts (Sumiński 1973; Okarma et al. 2004). Lynx’s coat and the number of spots on it, varies in relation to the place where they live and also depends on the season. Coat color ranges from yellowish-gray to brownish-red., It is an individual feature. In some situations, mottling may disappear and the coat becomes uniform. The underbelly, throat and groins are always creamy white (Sumiński 1973; Jędrzejewski et al. 2010). The length of an adult’s body is 100-150 cm, and the tail itself is 15-30 cm. The height at the withers the lynx reaches up to 75 cm. The average weight is 20 kg, but there are also specimens weighing from 12 to 35 kg (Szokalski 2014). Males are about 25% heavier than females (Keller 2001).
The Eurasian lynx eats a wide range of prey but tends to focus on roe deer whenever they are available. In their absence other ungulates, including red deer, are typically favoured, and various other small mammals are also often in the diet. Lynx will occasionally hunt gamebirds and, quite rarely, sheep (Sumiński 1973; von Arx et al. 2004). It is strictly carnivorous and will eat 1-2 kg of meat per day (Szokalski 2014).
According to global qualifications, Eurasian lynx belongs to the group of animals that fis considered to least concern animals [LC] (IUNC Red List 2019 ). However, in the scope of Poland, it is rigorously protected, including active protection since 1995. Eurasian lynx is a nocturnal, solitary animal, secretive, less mobile than a wolf, and keeping its territories away from human habitats. Its territories are also more overlapping. Therefore, estimating the number of individuals in the field is extremely difficult, labour-intensive and burdened with low detection. Nevertheless, monitoring of this and other predators should not be discontinued, as they have become a measure of the biodiversity and naturalness of forest ecosystems, and thus are included in the list of indicator species. This is due to the European Commission, obligated on Member States to take inventory (Simeonova et al. 2017). On their basis, the European networks of protected NATURA 2000 sites, can be designated. All Polish national parks and forest inspectorates are obligated to carry out the fieldwork to document the presence of lynx in Polish forests. Data analysis remains on the Mammal Research Institute of the Polish Academy of Sciences and the Institute of Nature Conservation of the Polish Academy of Sciences. The tracking of predator migration is aimed at checking the continuation of ecological corridors which connect Polish-European forest complexes (Jędrzejewski et al. 2011).
Lynx in Poland are divided into two main populations: the lowland and the Carpathian. Those, which are living in the north-eastern part of Poland characterized by a slightly lighter coat and less intensive mottling. Clear spots are an element of lynx’s coat from south-eastern Poland (Okarma 2000). Lynx are active for about 6-7 hours per day. They hunt almost exclusively at night (The Association for Nature WOLF 2008). The territories of males (up to 350 km2) are much larger from the females’ territories (up to 150 km2). The lynx can move a distance of 5-10 km, daily (Sumiński 1973; Jędrzejewski et al. 2002). Males do this further and more repeatedly than females (Samelius et al. 2011).
The increasing urbanization of western Europe results in habitat oss and diminished prey base, led to a significant reduction in the occurrence of Eurasian lynx population size there. Escalating deforestation and poaching remain major threats to their future (Jędrzejewski et al. 1999).
The aim of the study was to estimate the number of Eurasian lynx in Poland from 2004 to 2018 (the data was used from Central Statistical Office of Poland) and to predict the trend in the population development through 2027 (using the Holt’s model).