The Sayano-Shushensky Biosphere Reserve conducts counts of its mammal population every year. Methods vary depending on the season. The counts start in mid-February with winter tracking.
Winter tracking is carried out along an established list of routes. This enables specialists to keep track of yearly population statistics to analyse the status of certain species’ population. Winter tracking is a relative method used to make a comparative evaluation of the number of fresh (day old) tracks along a route. The relative indicator is the number of animal tracks per 10km of the route.
The work takes two days. On the first day (sweeping day), all the tracks left by animals in the snow are swept away and the trails are covered with snow. On the second day (count day), all the new tracks are recorded in the winter count logbook and marked on a map, indicating the species, direction of movement and number of animals that crossed the route. If an animal approaches the route but turns back, this is marked as one crossing. If a group of animals takes the same path, the record-keeper has to find the site where the animals part ways and count their number.
After covering the route, a specialist has to fill in the winter count records based on the logbook and map by drawing the route map and marking each track that crossed the trail with an arrow pointing in the direction of the animal’s movement (for example, Ro – roe, Bo – boar).
Visual encounters with animals are logged in the records, which list the time and place of the encounter, the number of animals, the distance, their age and gender.
During the winter count, researchers record tracks left by red squirrels, wolves, mountain hares, boar, Siberian roe deer, moose, Pallas’s cats, red deer, wolverines, lynxes, Siberian musk deer, snow leopards and sables. Other animals whose tracks are marked include ermine, Siberian weasels, weasels and otter, which are seen on the routes very rarely.
When processing the data obtained during the count, specialists make tables for each of the species, indicating the route, the count date, the overall number of route crossings, the number of crossings per 10km and the record-keeper’s surname. They use statistics from the past four years to estimate changes in the species’ population.
After warm weather sets in and before ice appears on the reservoir in late autumn, researchers have the opportunity to carry out visual counts of the Siberian mountain goat (Siberian ibex). This hoofed animal is a common species at the reserve and the snow leopard’s main food.
The visual count is carried out from the reservoir. This relative counting method allows experts to monitor the species’ population. Spring counts take place from 25 May until 5 June in the mornings (from dawn until 10 am) and evenings (from 7 pm until dark). Researchers keep record of females with this year’s brood and kids born last year.
The autumn (main) count takes place from 25 October to 5 November. The morning session lasts from dawn until 11 am and the evening session – from 5 pm until dark. The count includes all the animals of reproductive age.
A visual count is done by two record-keepers at a time from aboard a launch sailing at a speed of 12-15km/h at a distance of 100-150m from the shore. After spotting animals with the naked eye, specialists use binoculars to determine their exact number, age and gender.
While studying breeding peculiarities during animal population research, attention is focused on the general fertility of females and how it depends on various factors. The key research tool in birth dates evaluation is the visual count of the year’s offspring in groups of females over the entire summer season. By monitoring the correlation between the number of the year’s offspring and the number of females throughout the year, it is possible to assess the relative mortality rates for young animals during the first year of life.
A count on open mountain slopes is a classic count method: observers follow a permanent footpath along the bank of a river and survey open mountain slopes through binoculars from the earlier chosen permanent monitoring sites. This method is used to count Siberian mountain goats in the Bolshiye Ury River basin.
When counting forest reindeer, a rare hoofed species listed in the Red Data Book of the Russian Federation, the method is slightly altered. Specialists first map out a route through mountainous terrain, and, as they follow the route, they survey the slopes in search of reindeer. Over the 40-year history of the Sayano-Shushensky Biosphere Reserve, researchers have rarely come face to face with a reindeer. If they were lucky, they tried to make a thorough description and take photos of the animal.
Since 2007, when active snow leopard population research began, motion-sensor cameras have been used to count animals in the reserve.
Snow leopard counts in the reserve and the protected area around it are carried out by identifying individual animals, using images from motion-sensor trail cameras. The leopards that inhabited a certain area in the past are identified by their digital profiles. The newcomers are identified by spot patterns on the head, body and tail. As a rule, spots and rosettes on the shoulders and haunches are taken into account.
Important factors in trail camera monitoring are the procedure and method of installing the cameras: they are installed in areas where markings of one or more snow leopards were found during winter tracking. Then GPS coordinates and location on the ground of these markings are determined. The traces include urine, scrape and scuff marks. These are important signposts both for leopards and other animal species sharing the same habitat. Urine markings are the most telling, so a camera installed nearby is the most effective.
For more precise identification of individual animals, trail cameras are installed near markings and on animal trails in a way that would allow a camera to capture both front- and side-view shots.
The trail camera count lasts all year round. Specialists study camera images and carry out technical maintenance during both snowy and snowless seasons.
Data from trail cameras help assess the populations of other mammals in the reserve, for example, the Pallas’s cat. Photos captured with trail cameras confirmed the presence of the Pallas’s cat in the reserve and helped collect the necessary information about the forest reindeer range. Females with offspring are often caught on cameras, which enables researchers to study the populations of individual species and their reproduction.
In the future, considering the fact that many parts of the Sayano-Shushensky Biosphere Reserve are hard to reach, scientists believe it expedient to use quadcopters, as well as powerful optical equipment for photo and video monitoring in order to collect data for population trend analysis and also to obtain precious snapshots of wildlife.