Zvýšení biologické kvality jedinců tetřívka obecného (Lyrurus tetrix) připravovaných pro záchranné programy

Abstract

In the middle of the twentieth century, a downward trend in grouse numbers in Central Europe became evident. Along with the decrease in the number of birds, the fragmentation and subsequent shrinking of the range of forest fowls such as the capercaillie (Tetrao urogallus), the black grouse (Lyrurus tetrix) and the hazel grouse (Bonasa bonasia) began to manifest itself. This trend continues until now and the occurrence of these species in the Czech Republic and Central Europe in general is threatened. One of the segments of saving the species in situ is the support of the population by artificially reared or translocated individuals. First of all, however, it is necessary to solve the problem of the biological quality of the individuals used, which largely depends on the state of their digestive tract, the quality of the food and the development of behavioral patterns necessary for the intake of natural food in the wild. Therefore, analyzes were made of the food supply of black grouse in the wild and potential feed components for black grouse in aviary breeding (Wendes method – dry matter, N substances, fats, ash, fibre, BNLV, expressed in %). Subsequently, on the basis of the analysis results, a recipe of a feed mixture of seeds, dried shoots, fruits of woody plants and dried insects was prepared, suitable for rearing and preparing grouse birds for adaptation to natural conditions. It presents a diversified food consisting of six types of cereals, two types of legumes, four types of oil seeds and another four types of seeds, fruits and dried shoots. The feed mixture of natural plant components was supplemented with an animal component – dried developmental stages of mealworm (Tenebrio molitor).