Abstract: In Russia, traditions of track observations and the use of tracking techniques in studying the ecology and behavior of mammals were founded by A.N. Formozov. An analytic review of his data on large carnivorous mammals (tiger, snow leopard, wolf, brown bear, wolverine, and others) is given. A special detailed observation of animals' tracks as a source of information on their life is shown only to start. The efficiency of track observations in various fields of studies, including counting animals, is estimated. The values of day and night distances for various animal species, given in literature, have never been properly substantiated methodically. The tracking method is the most effective in studying the use of the home range by animals, drawing the network of their movements and scent-marking behavior. The hunting behavior of large predators in dense forests is can only be deduced by observing their tracks. In some cases, the use of tracking has a distinct advantage over radio tracking. The main propositions are illustrated by the materials of the author obtained in various Russian regions (in forests of the northern Russian Plain and southern Far east) for 1958-1998.

Abstract: Serum oestradiol and progesterone concentrations were measured at weekly intervals for six months, and correlated with daily behavioural observations in two adult female snow leopards (Panthera uncia). Three oestradiol peaks (> 21 pg ml-1; interval 3.6 weeks) were identified in a snow leopardess housed alone (two more were probably missed because of the weekly sampling schedule), and three oestradiol peaks were identified in a snow leopardess housed with a male as a breeding pair (interval 6 weeks). Daily frequencies of feline reproductive behaviour averaged 1.77 observations per observation period during weeks of high oestradiol and 0.62 during weeks of low oestradiol. Progesterone concentrations did not rise above baseline values (< 2 ng ml-1) in the isolated animal, but 6 weeks of high progesterone concentrations (4.9- 38.8 ng ml-1) was recorded in the paired snow leopardess following mating. No offspring were produced. Snow leopards were observed daily for an additional 4.5 years. Sexual behaviour peaks could be clearly identified from December through April, and average daily sexual behaviour scores were higher during these months than during the rest of the year. Intervals between sexual behaviour peaks for the isolated snow leopardess averaged 3.03 weeks. The sexual behaviour of the paired snow leopards decreased for 8-9 weeks following mating when no offspring were produced, and decreased for 13 weeks in one year when a single cub was born.

Abstract: The snow leopard (Uncia uncial Schreber, 1776) is the most poorly studied species of the cat family in the world and, in particular, in Russia, where the northern periphery of the species area (no more than 3% of it) is located in the Altai-Hangai-Sayan range [1]. It is generally known that the existing data on the Russian part of the snow leopard population have never been a result of targeted studies; at best, they have been based on recording the traces of the snow leopard vital activity [2]. This is explained by the snow leopard's elusive behavior, inaccessibility of its habitats for humans, and its naturally small total numbers in the entire species area. All published data on the population status of the snow leopard in Russia, from the first descriptions of the species [3-6] to the latest studies [7, 8] are subjective, often speculative, and are not confirmed by
quantitative estimates. It is obvious, however, that every accurate observation of this animal is of particular interest [9]. The purpose of our study was to determine the structure and size of the population group presumably inhabiting the Western Sayan mountain ridge at the northern boundary of the species area