What are the chances of your seeing a wild board appearing from drainage pipes? If you answered zero, you would be wrong. Such an event is quite possible on the 36th kilometre of the Moscow Ring Road (MKAD), where boars visit this part of Bitsevsky Forest. Tracks show that boars reach Moscow through…drainage pipes. This is their way to cross the motorway. These pipes serve as an eco-tunnel and a safe route under the road.
Ecologist Viktoria Shlyakhovaya, an employee of the Bitsevsky Forest Eco Center, admits that she too would like to walk that route. She is equipped with binoculars and a small notepad that she makes notes in from time to time. Why? In order to track the forest’s creatures. The count is conducted in the winter, usually in February, so that migration would not affect the results. Mospriroda chief expert Valentin Volkov adds that “It makes not sense to postpone the count till March when there may be no snow at all due to the early arrival of spring.” The best way is to do the count after a snowfall, so that all tracks are visible and clear. Experts always watch the weather forecast before conducting their counts.
Tracking weather forecasts also makes sense when you consider that you’ll have to spend several hours outside. It is just minus six degrees Celsius, but it feels like it is minus 16. Viktoria admits that she likes doing the count when it is cold: “The tracks are very clear right after a snowfall and especially in the sunny, cold weather.”
First we walk along a wide, trodden path; this section is part of an eco-trail. Along the path banners with information about the park and its inhabitants are installed: over 28 mammal species, over 100 bird species, three reptile species and six amphibian species.
Today Viktoria will count birds and mammals. There are many tracks on the snow, but most of them are old and have already been counted. It would be difficult for an inexperienced person to tell the difference between old and fresh tracks. But experts remember all the tracks they saw, for instance, last week. Here, a fox ran by, here a hare jumped. These small tracks belong to a mouse that then dove into a snow tunnel. “This looks like an igloo,” said Valentin, pointing at the mouse hole.
Above our heads are bird feeders made of wood, plywood, cardboard, milk cartons and plastic bottles. Chickadees are used to people and even eat out of their hands. A female bullfinch with a grey chest is cautious and prefers to watch from above. We left some nuts in the feeder and a squirrel immediately appeared. It was too shy to take food and disappeared in the branches. But it’s okay; it has been counted already.
Red square poles mark the squares into which the park is divided. “These poles help people orientate themselves in the forest because they correspond to coordinate points,” said Valentin Volkov. “The smaller numbers are on the northern side.” It means, we were moving southward, and can already hear the traffic on the MKAD.
According to the rules, eco-trails should not go along roads and wide fire-breaks. We have now walked deep into the forest, along narrow, barely visible paths. We see more tracks left by hares and foxes. Viktoria suggests we visit the leshy, not a forest spirit, but a wooden sculpture with carved eyes, nose and a grin. The tree stump has stood here for 15 years but has yet to acquire the customary legends about its existence. We place some nuts for squirrels on the top of it.
The path goes through a fir forest. Little remains of the original forest that was planted in 1910. Many trees perished during the draught of 2010 while bark beetles killed many others. On the other side there are rows of recently planted young firs.
Forest Acrobats and Red Data Book Species
The next stop is the bird feeding ground. Bread heals on tree branches attract the birds, as well as feeders with seeds and more bread. “I like to visit this place and add new birds to my list,” Viktoria said. While on location, we managed to add six bird species to the list. The one with ginger head and chest is a robin. It is a migratory bird, but experts have seen it in Moscow in winter for four years.
The long-tailed titmouse with a long black tail is listed in the Red Data Book (endangered species list). The yellow-chested bird is the great titmouse, often called an “acrobat” for its swiftness. The Eurasian blue titmouse looks quite similar but with one difference: its hat is blue, not black. On the snow, under a shrub, tree sparrows and a common treecreeper can be seen feeding. Bread is unusual food for the latter: the treecreeper is an insectivore and only eats bread when it is very hungry.
Nearby we noticed two jays, a great spotted woodpecker and a squirrel, which was busy showing off its furry tail.
Mathematics in the Service of Zoology
There are over 100 routes developed for winter counts totaling over 300 km in Moscow’s natural areas. About 13-15 counts are held every year. The main task of these counts is to cover as much area as possible.
Bitsevsky Forest has seven approved routes that were developed by Mospriroda experts and continue to be used from year to year. How were they chosen? The idea was to include various zones, such as forest or field, all in one route. This approach allows experts to see an array of animal species.
The main objective is to assess the species and the population
Valentin Volkov explains. “We document all the tracks and animals that notice.” Tracks are not only pawprints. It might be excrement, for instance, that can help distinguish a brown hare from a blue hare. Hares also leave chewed branches, while boars leave hair when scratching their backs against tree trunks.
Viktoria inspects not only short routes of 5-6 km, but tries to walk through the entire forest. She keeps a special book about all her encounters with animals, including the date, time, place, the weather, animal species and their numbers. These notes are later compiled into a report.
The count is still on, but it is difficult to say for certain just how many animals actually live in the forest. Once the animals are counted in late March-early April the data will be submitted to the Department for Environmental Management and Protection, and then to the State Hunting Register.
This methodology was developed and approved in 2010. It is based on the principles used for counting hunting resources in various hunting farms. Zoologists write down the number of animal tracks that cross a route and put them on a map. “Then special formulas are used to calculate the number of crossings using the area, types of forest, the number of clearings,” adds Volkov.
The formula is D = A x K, where D is the number of animals per an area unit; A is the average number of crossings of one species per day per unit of length; K is the correction factor related to the length of the daily route of an animal during the counting period.
However, this mathematical approach is good for large forests, while Moscow’s forest areas are small and oddly shaped. “We have to walk twice as much, because if we see an interesting track we have to follow it,” said Valentin. Following the track, however time-consuming, helps to avoid counting the same animal twice. Also, the zoologist collects information about the animal’s habitat, feeding and hunting sites and its resting areas in the daytime and at night.
There will always be margin of error, Valentin reminds us. Sometimes it is hard to determine how many animals have left tracks on the snow. And if some of them can be distinguished, for instance the tracks of a male marten are bigger than those of a female, it is not that easy with other animals. That is why the count is conducted by zoologists, not amateurs. One nature lover recently wrote on Twitter that he saw a chipmunk on Vorobyovy Gory. Obviously there are no chipmunks there, so he obviously mistook a mouse with a dark stripe on its back for a chipmunk.