There is an old saying in China: A good tiger is no match for a pack of wolves. But in neighboring Russia, there is a saying that a solitary tiger can suppress a pack of wolves. Now, Professor Dale Miguel, director of the "Amur Tiger Conservation Project" jointly launched by the Wildlife Conservation Society (WCS) and the Russian government, has summarized some data for us over more than 100 years to clarify tiger A true relationship with wolves.

The study area is the Sikhote Alin Reserve, which is also the main distribution area of ??Siberian tigers today, with a current area of ??about 4,000 square kilometers. Today's two protagonists are tigers and wolves, specifically the Siberian tiger and the Mongolian wolf. The Siberian tiger is the largest tiger subspecies and the largest cat. Male tigers weigh 155-212 kg and female tigers weigh 110-136 kg. The scientific name of the Mongolian wolf is Canis lupus chanco. It is called the "Northern Subspecies" in "Anthology of China", which means a wolf living in northern China and weighs 22-37 kilograms.

As the saying goes, "There is no room for two tigers in one mountain." Tigers are strictly solitary animals. They are always alone except during mating season and when the female tiger is raising her cubs. The wolf camp lives in groups, but the group size of Mongolian wolves is not large. Look at the bar chart below. According to our country's survey, wolf packs of 1-6 are common in Inner Mongolia, with a maximum of 10; while wolf packs in Heilongjiang are mostly lone wolves, with the largest pack having 7 wolves.

The ebb and flow relationship between Siberian tigers and wolves

Amur tigers were common in the far southeast of Russia from the late 19th century to the early 20th century. Later, it decreased sharply due to indiscriminate hunting and killing by humans, reaching a historical low in the 1940s. Since the Soviet government introduced a law strictly prohibiting tiger hunting in 1947, the tiger population continued to recover and grow for 40 years, reaching its peak in the late 1980s and early 1990s.

The distribution and number of wolves show an opposite trend to that of tigers. From the end of the 19th century to the beginning of the 20th century, there were no wolves at all in the far southeast of Russia, or they were very rare. Former Soviet ecologist Abranov believes that at the beginning of the 20th century, as the distribution of tigers declined sharply, wolves began to appear in the Sikhote Alin Mountains.

According to the research of Russian zoologist Eugene, wolves first entered the more populated Ussuri River Basin and Xingkai Lake area. The tigers here were killed by the Russian Empire in the late 19th and early 20th centuries. The colonists were wiped out. During this period, the habitats in the area were mainly destroyed forests and meadows, where wolves lived on roe deer and livestock and gradually established a foothold.

From the 1930s to the 1940s, the number of tigers in the Sikhote Alin Mountains also declined. The wolves took the opportunity to expand based on the Ussuri River and Xingkai Lake, and soon occupied the entire southeastern Russian Far East. area. After the 1950s, as the tiger population recovered, the number of wolves in the area gradually declined. Today, wolves are very rare in areas where Siberian tigers are distributed, with only some sporadic individuals and small groups seen.

Many records show that there is a negative correlation between the number of wolves and Siberian tigers. In the Xingkai Lake area, when tigers were extinct due to human persecution in the early 20th century, wolves came to the area and gradually expanded the population; but when tigers returned to the area in the 1990s, the wolves disappeared. The area has a large population and severe habitat fragmentation, which may not be suitable for tigers to survive after all. When tigers disappeared from the area again at the beginning of this century, people were surprised to find that wolves were back.

In nature reserves, the numbers of tigers and wolves have been monitored, and their changing trends have been specially recorded. For example, in the Razovsky Nature Reserve, former Soviet zoologist Bromley discovered that there were no wolves here before. By the 1940s, due to the extremely low density of tigers, wolves overran the area, and humans had to kill 105 wolves. From the 1960s to the 1980s, as tiger numbers recovered, wolf numbers continued to decline. By the early 1990s, the number of tigers was large and stable, and it was difficult to see traces of wolves. During surveys in 1992 and 1993, there were no traces of wolves in the reserve.

The population dynamics of tigers and wolves are the most well-documented in the Sikhote Alim Reserve. Bromley reported that before the 1930s, elderly local residents had never seen wolves on the eastern slopes of the Sikhote Alin Mountains. As tiger numbers dwindled, wolves invaded the area and thrived. Although tiger numbers began to rebound in the 1950s, until the early 1960s, there were very few tigers in the entire reserve. During this period, wolves were still considered common animals, although people hunted them in large numbers to control their numbers. After 1963, with the expansion of protected areas and the implementation of better protection measures, the distribution and number of tigers recovered rapidly.

Based on field survey data in the 1970s, two zoologists from the former Soviet Union, Gromov and Maushkin, opposed this statement that has had a profound impact on Russia: it was the emergence of tigers that had an impact on the wolf population. It had an inhibitory effect and even pushed it to the brink of extinction. But when we look back at data from the entire 20th century, it becomes clear that their observations were made during a period when tiger and wolf numbers were extremely uneven, when wolf numbers were at their peak and tigers were just recovering from the brink of extinction.

In the 1970s, tigers and wolves each existed at medium densities for about 10 years. In the early 1980s, as the number of tigers steadily increased, the number of wolves in the reserve became increasingly rare.

The mechanism by which Siberian tigers suppress wolves

Although the negative correlation between the populations of tigers and gray wolves is clear, the mechanism by which tigers cause the decline in gray wolf numbers is not yet clear. Zoologists have put forward three hypotheses:

The theory of food grabbing. In North America, packs of wolves have seriously affected the nutritional status of mountain lions by frequently snatching their prey, resulting in increased mortality of mountain lions and limiting their numbers and distribution. But this occurs in open-field habitats in North America. In the forests of far southeastern Russia, it is not common for tigers to snatch wolf prey due to the restricted vision of animals in the forest. Former Soviet zoologists Gromov and Maushkin discovered tigers stealing prey from wolves, and also found wolves cleaning up the carcasses of prey killed by tigers. Therefore, food grabbing cannot be the main reason why tigers restrict wolves.

Avoidance. Russian zoologist Eugene discovered that wolves will actively avoid tiger territory, which also leads to the spatial separation of the two animals. When the number of tigers increases in the reserve, wolves can only appear in the areas around the reserve. . However, simple avoidance does not seem to explain the decimation of wolf numbers across such a large area.

The theory of hunting and killing. Most zoologists believe that tigers do not directly prey on wolves. Zoologists have only recorded four cases of Siberian tigers killing wolves, but Siberian tigers are notorious killers of domestic dogs. According to official records, between 1957 and 2002, tigers were killed in Sikhote Alin and surrounding areas. *Killed 104 dogs. In South Asia, Bengal tigers have also repeatedly killed another canine species, the jackal. Many times, one carnivore is directly hunted by another carnivore, which is an important factor in limiting its distribution and population. Therefore, despite the lack of clear evidence, Professor Dale Miguel still believes that the direct hunting of wolves by Siberian tigers is likely to lead to a sharp decline in the distribution and number of wolves in the far southeast of Russia, and to weaken their functions in the ecosystem to a non-significant role. important promoter.

The hunting theory has been confirmed to some extent in recent years. In 2010, a resident female tiger died of canine distemper in the southern part of the Sikhote Alin Reserve, and a wolf couple soon arrived in her territory. However, the story is not over yet. One of the wolves died of canine distemper soon after, and the other was last seen a few years later when it was being chased across the road by a tiger. The wolf was never seen again. The female tiger Ilona released into the wild by Russian President Vladimir Putin killed and ate two wolves in the first winter after its release. The picture below shows a wolf that tigress Ilona killed.

Wolves killed by "Putin Tiger" in the wild

The "Soviet Mammals Volume One" published in 1967 pointed out that the only natural enemy of wolves is tigers. There have been no wolves in the Ussuri area since ancient times. Wolves will only appear after tigers are eliminated by humans. It has also been noted that when tigers reappear in an area, wolves will disappear. This represents the unique knowledge of Russian zoologists.

The presence of tigers has even changed the distribution of wolf subspecies. The Ussuri area is mainly a forest habitat, and should have been home to forest-type Eurasian wolves (distributed in the vast forest areas of Europe and Siberia). Why are grassland-type Mongolian wolves inhabiting today? Russian zoologists pointed out that there were originally no wolves in the forests of the Ussuri region. In the early 20th century, with the deforestation of the taiga and the disappearance of the wolf's main natural enemy, the tiger, Mongolian wolves came from the west and The southern region moved in.

The world's top expert on gray wolves, Mechi, is blunt about the fact that tigers crowd out wolves. He said that almost no carnivores can compete with wolves, with the exception of tigers. In Southeast Asia, wolves are absent from much of the tiger range. Whether this negative correlation is causal is unclear, but evidence from the Russian Far East suggests that tigers have suppressed wolf populations to the point of local extinction, or reduced wolf populations to the point where they are not functional in the ecosystem. The characters have become less prominent.

Only when humans hunt tigers, causing a sharp decline in tiger numbers, can wolves escape the fate of being squeezed out by tigers. Although many studies have documented competition between large carnivores, it is quite rare for tigers to drive wolves to the point of local extinction.

So far, the mechanism by which tigers lead to the decline in gray wolf numbers is not yet clear, leaving it to zoologists to continue exploring. We can see that the group size of Mongolian wolves is not large, usually only one or two. Even in a rare large group of seven, the total weight of the individuals is only the same as that of an average male tiger. This may be because Mongolian wolves cannot compete with the Northeast. Tiger reason.