Three of the five cubs in a closely monitored family of wild Siberian tigers have begun living independently in Northeast China, offering a glimpse into the animals’ behaviour as habitat restoration and conservation efforts support local breeding.

The cubs began separating from their mother in August, while the other two remain with her, Chen Xiaocai, head of the general affairs division of the Northeast China Tiger and Leopard National Park administration, told the Global Times on Sunday.

Male cubs generally leave their mothers first. Young tigers typically begin living independently at around 18 months to two years of age, Chen said.

The three cubs that have left their mother remain in the Hunchun area of Jilin province in northeastern China and occasionally cross the border into Russia. The park continues to monitor their movements through its wildlife tracking system.

The family, comprising a mother tiger named Ying Xiong, meaning “Hero”, and her five cubs, was first detected by infrared cameras in November 2025. According to the park administration, it was the first documented case of wild tiger quintuplets in China.

The female tiger, registered as GH005F in the park’s monitoring database, is believed to have given birth around June 2025, several months before the family was first spotted.

Recent monitoring data also suggest that the mother may be allowing her weakest daughter to take over her territory, a possible behaviour Chen described as “territory gifting”.

The mother is better positioned to establish a territory farther away, while her daughter may find it more difficult to secure one, Chen explained. Giving up an established territory could therefore improve the younger tiger’s chances of settling successfully. However, he stressed that this remains a possibility suggested by monitoring records rather than a confirmed behaviour.

The family’s development comes as the park records more cases of local tiger breeding. At least three other tiger families, each with four cubs, have also been monitored, Chen said.

Sika deer, roe deer and wild boar provide food for the park’s large predators. The wild sika deer population has more than tripled from earlier levels, making the species increasingly common in the area, he added.

A greater supply of prey allows mother tigers to hunt more frequently while nursing and raising their young, helping them support larger litters.

Reduced human disturbance has also made breeding habitats safer. Forest operations and other activities previously brought people into areas used by tigers, but conservation measures have significantly reduced such interference in core habitats, Chen said.

The park’s tiger population is now growing mainly through local reproduction rather than the arrival of animals from across the Russian border. As habitats recover and human disturbance declines, more tigers are settling in the area and forming breeding families.

Official figures from China’s National Forestry and Grassland Administration show that the number of wild Siberian tigers in the park rose to 72 in 2026 from 27 in 2017. The wild leopard population also increased, reaching 115 from 42 over the same period.

Of the animals monitored, 21 tigers and about 27 leopards have been recorded moving between China and Russia, Chen said.

The two countries signed an agreement in 2024 to establish a transboundary protected area for big cats, strengthening cooperation on tiger and leopard conservation, anti-poaching efforts and cross-border movement. The adjoining protected areas in China and Russia cover nearly 17,000 square kilometres, according to Chen.

The park’s wildlife monitoring system combines satellite observations, drones and ground-based cameras to track animals and record their movements.

Hu Xinyu, a senior manager at Jishi Media, which provides technical support for the system, told the Global Times that a 700 MHz communications network transmits footage from cameras in the forest to monitoring centres. Images and videos can reach the centres within about a minute of being captured.

Artificial intelligence helps identify species and individual tigers and leopards. However, identification can be difficult when camera angles are poor or an animal’s distinctive markings are only partially visible, Hu said.

The system achieves 90% accuracy in identifying species and 80% accuracy in distinguishing individual tigers and leopards, he added.

The Northeast China Tiger and Leopard National Park covers 19 former nature reserves. It began operating on a pilot basis in August 2017 as one of China’s first five national parks and was formally established in 2021, according to Xinhua News Agency.

Conservation work has included restoring 2,200 hectares of forest, establishing ecological corridors, repairing key wildlife passages and maintaining continuous anti-poaching patrols. Together, these measures have expanded and improved habitats for the region’s tiger and leopard populations.