The phrase "captive wolves" refers to wolves that are held in captivity, meaning they are enclosed or confined, rather than living freely in the wild. Full definition
The whole alpha dog theory comes from a 1930s study of captive wolves. (littledogtips.com)
Studies with captive wolves demonstrate that while you can raise wolves to be somewhat tolerant of people, they retain a suspicious nature and are extremely difficult to train. (animals.howstuffworks.com)
In particular, it allowed FWS to release captive wolves only into a small zone within Arizona's Blue Range of mountains; the Blue Range Wolf Recovery Area covered just 16 % of the approximately 90,000 - hectare region. (sciencemag.org)