Article by biologist and wild game expert Alexander Batalov in the fourth issue of the Zvezda Priamurya magazine. Balatov is head of the Durmin game farm and executive manager of Amur tiger population monitoring in the Khabarovsk Territory.

It is well known that tigers prefer to live in the south of the Khabarovsk Territory, the northern limit of their natural habitat. Tigers are common in the Bikin, Vyazemsky, Lazo and Nanaisky districts. The predators also visit the Khabarovsky, Komsomolsky and Sovetsko-Gavansky districts for short stays or in search of new areas with food. In these parts, tiger paw prints can be found in any forest inhabited by hoofed mammals, their main prey, but mostly on taiga paths and trails where tigers can move more easily and more quickly spot peers and prey.

Tiger paw prints look similar to those of a domestic cat, only far bigger. The size of the paw prints indicates the size of the animal. A paw print measuring 16 cm across or more belongs to a very bulky male tiger, 14 cm to a medium-sized male, and 10−12 cm to a female tiger. There are no traces of claws as they are retractable. The width of the front paw’s heel, which is always larger than the back paw’s, indicates the gender and age of the animal. A paw print shows one plantar pad (heel pad) and four digital pads. A heel over 10.5 cm across belongs to a mature male, under 10 cm – to a mature female or a young male. Heels measuring between 5.5 and 6.5 cm belong to five-month-old tiger cubs. At this age, they leave their den and follow the mother. One-year-old males have the same sized heel on the front paw as their mother (sometimes wider). Females reach their mother’s heel width by 18 months. At this age, young tigers gradually start to become more independent and hunt on their own.

By the age of two, tigers are mature predators. Now each of them has its own life and heel size, which may increase insignificantly by the age of four to five years and later depends on the animal’s weight, particularly with the males. The heavier the male, the larger its heel. The largest male we recorded, with a heel width of 13 cm, lived until 2013 in the Lazo district in the basin of the Obor, Durmin and Kiya rivers and on the right bank of the middle section of the Khor river. Many forest rangers and hunters saw his paw prints and were utterly stunned.

At the moment, two large male tigers with a heel width of 12 cm live in two modelled areas of this district covering 400,000 hectares.

The most common heel width among mature males is 11 cm on average in 7 out of 10 animals, and 9 cm among females in the same ratio. Likewise, 7 out of 10 adult men wear a size 42 shoe, compared to size 36 for women. Mature tigers, both male and female, have back heels that are 1 cm shorter than the front heels.

It may be difficult to distinguish between some tigers with identical heel sizes on the same territory but they give themselves away with fresh paw prints found at long distances from each other in a short span of time. A tiger’s paw prints are identified by the length of its step and the distance between the front paw prints on an even surface. Some animals demonstrate individual habits (always walking through the same place), others have injuries on their paws (marks) that set them apart from their peers.

At the upper reaches of the Durmin river, only one out of three mature males living in this area has the courage to cross the bridge. An easily recognizable tigress has been living in the Bolshekhekhtsirsky Nature Reserve for 15 years − she has one digit missing on her right hind paw.

Other telltale signs of tigers’ presence include scrapes, or toilets in the ground, and claw marks on trees, as well as urine and feces that the predators leave behind. The scrapes are normally made by males and females in any season. The sights look like tire tracks, which is the result of the predator’s energetic scratching of the top layer of soil making it into a pile of leaves, snow and soil. Here tigers resemble domestic cats preparing to have a toilet break.

Just like their feline cousins, tigers leave their feces and urine on top of the heap but they do not cover them up. Many scrapes remain empty or contain drops of urine but they are clearly visible landmarks left by the tigers and, evidently, make good visual and scented signposts. Their number increases in places frequented by the predators and particularly at the sites where they meet with their peers, near special marked areas and also near the remains of their prey.

Tigers leave claw marks on trees using their front paws, standing up on their hind legs and leaning on the tree trunk. They tend to prefer large foliage trees, rarely conifers, without lower branches (birch trees, lime trees, fir trees) that stand out in the wood and are on their regular routes. Tigers occasionally approach these trees and inspect them, sniffing for possible markings, and often leave new ones. If they sense a new smell left by other tigers, they once again scratch the tree, rub their neck and chest against it, lick and bite the marked places and finally spray more urine and the specific anal secretion at the site of interest. These marked trees carry clear claw traces, predators’ hairs and dark multi-layered scented stains of different sizes left by tigers’ numerous markings.

In addition, the predators’ harsh smell fills the air, particularly during the warm season. But a human can sense the smell in winter too if he/she blows at the stain with the warmth of one’s breath. The specific tigers’ scent comes from the anal secretion produced by both males and females from near the tail set, on both sides of the rectum with secretion coming out from near the sphincter. The milky secretion is sprayed when the tiger lifts its tail and is automatically emitted with excrements. It contains information about the age, gender and physiology of each species. Apart from trees, tigers use their urine and anal secretion to mark large tree roots and big rocks on their way.

The tree markings, or the so-called post boxes, last for years and are used not only by other tigers but also by individual mature males of the brown and white-chested bears sharing the territory with the tigers.

Tigers’ feces and urine that can be clearly seen in winter on their paw prints and scrapes, are barely visible in summer. However, they can be tracked by groups of insects, particularly various butterflies that flock to the tigers’ “traces” for protein and mineral nourishment. Closer examination of the tigers’ feces has revealed the remains of the prey eaten by the tiger, and, depending on the degree of digestion, the approximate time of the predator’s successful hunt. The prolific digested meat with a small amount of hair in the feces indicates that the tiger’s last prey is not far from the tiger’s latest toilet stop.

The tiger’s fresh paw prints and crows’ cries in the forest testify to the presence of imprints. When they are feeling sated and comfortable, tigers often roll around on the ground or in the snow and lie on their side. In winter, such imprints allow scientists to measure approximately the animal’s size – the body and tail length and width, and also discover pieces of ice containing the prey’s fresh blood.

Researchers’ ability to find and “decode” tigers’ paw prints and traces allows them to count the predators’ population on vast territories, determine the gender and age of the tiger population, how it is distributed in various areas, study their food and many other things crucial for tiger research and the protection of this rare animal.