Population size and distribution of the capercaillie in Poland in the 21st century

The data on the distribution and number of the capercaillie Tetrao urogallus in Poland for the period from the end of the 20th century up to 2017−2018 is presented. The capercaillie is a sedentary forest grouse living in old mountain forests and within the boreal zone. Since more than a century, the decrease in the numbers of the species has been observed, interlinked with the extinction of isolated populations. Within the present borders of Poland, a 1925 questionnaire study noted 2200−2700 individuals. In the 1960s, the national population was estimated at 1700−2000 birds, living in five isolated populations. In 1985−1995, the population numbers of the capercaillie dropped to approx. 466−700 individuals in four regions, and in 2000 it was estimated at 470−570 birds. According to the results of the censuses performed in 2017−2018, the size of the capercaillie population risen to 523−631 individuals and 59−69 lekking grounds. Currently the capercaillie occurs in four isolated regions. These are the Western Carpathians (the Beskid Sądecki, Tatry, Gorce, Babia Góra, Beskid Żywiecki, and the Beskid Śląski ranges) where 284−326 individuals live and 35−41 leks are active. In the Solska and the Lasy Janowskie Forests (Lublin region), the population was estimated at 132−184 individuals and 12−13 lekking grounds. In the Augu− stów Forest (Podlasie region) 36−46 individuals and 5−7 leks were found. In the Bory Dolnośląskie Forest, where native capercaillies got extinct during the last decade, the reintroduction program resulted in the rebuilding of their 65−75 population (with 6−7 leks). The restitution of the species in the Piska Forest has begun. During the last 20 years, populations in the Carpathian national parks have been stable, although fluctuating in numbers. The increase in the number of individuals in the Augustów Forest as well as in the Sądecki and Beskid Śląski Mountains is an after−effect of the release of birds from breeding centers or translocations. In other strongholds, fluctuations or decreases have been recorded, including wisible in the Beskid Żywiecki Mountains