Seven lions in South Africa are to be tranquillised, placed in steel crates and loaded on to a charter flight to Rwanda on Monday, restoring the predator to the east African country after a 15-year absence.

Cattle herders poisoned Rwanda’s last remaining lions after parks were left unmanaged and occupied by displaced people in the wake of the 1994 genocide, according to the conservation group African Parks, which is organising the repopulation drive.

It said two parks in South Africa’s KwaZulu-Natal province with “relatively small, confined reserves where it is necessary to remove surplus lions” are donating the big cats to Rwanda. The seven – five females and two males – were chosen based on future reproductive potential and their ability to contribute to social cohesion, including a mix of ages and genetic makeup.

From Monday they will be transferred to Akagera national park in north-east Rwanda by truck and plane in a journey lasting about 26 hours. African Parks said: “They will be continually monitored by a veterinary team with experience in translocations. They will be kept tranquillised to reduce any stress and will have access to fresh water throughout their journey.”

Upon arrival at the 112,000-hectare park, which borders Tanzania, the lions will be kept in quarantine in a specially erected 1,000m² enclosure with an electrified fence for at least two weeks before they are released into the wild.

The park is fenced, but the lions will be equipped with satellite collars to reduce the risk of them straying into inhabited areas. African Parks said: “The collars have a two-year life, by which time the park team will have evaluated the pride dynamics and only the dominant individuals in each pride will be re-collared.”

As a wildlife tourist destination, Rwanda is best known for its gorilla tracking safaris. But Akagera, a two-hour drive from the capital, Kigali, is home to various antelope species, buffaloes, giraffes and zebras, as well as elephants and leopards. It attracted 28,000 visitors in 2014.

Last year, as part of the preparations for the reintroduction, the Akagera team ran a sensitisation programme in communities surrounding the park to promote harmonious co-existence with lions.

Yamina Karitanyi, the head of tourism at the Rwanda Development Board, said: “It is a breakthrough in the rehabilitation of the park ... Their return will encourage the natural balance of the ecosystem and enhance the tourism product to further contribute to Rwanda’s status as an all-in-one safari destination.”

The International Union for Conservation of Nature listed the lion as vulnerable in an update this month of its red list of species facing survival threats. It noted lion conservation successes in southern Africa, but said lions in west Africa were critically endangered and rapid population declines were also being recorded in east Africa.

African Parks cited human encroachment on lion habitats and a decline in lion prey as reasons for the population drop. It identified a trade in lion bones and other body parts for traditional medicine in Africa, as well as Asia, as a growing threat.

Peter Fearnhead, the chief executive of African Parks, which manages Akagera and seven other national parks on the continent, said: “The return of lions to Akagera is a conservation milestone for the park and the country.”