European bison were extinct in the wild by 1927 and have been reintroduced from captive-bred animals into several European countries, with welfare management of reintroduced and semi-wild populations ongoing.
Bison welfare in rewilding contexts involves balancing wild behaviour expression with practical management requirements. Population health monitoring requires capturing animals for veterinary assessment, causing acute stress. Disease risks from contact with domestic cattle require veterinary oversight. Population regulation may require translocation or in rare cases culling.