California Code, Fish and Game Code - FGC § 3214

Domesticated game breeders or other persons holding domesticated game mammals in captivity shall confine the mammals in escape-proof cages or enclosures.  In the event any of the mammals escape from the cages or enclosures, the owner shall immediately make every reasonable effort to recapture them.  If the owner fails to recapture the escaped mammals, the department may capture the mammals or remove them from the wild by whatever means may be necessary if, in the opinion of the department, the mammals may conflict with native species of birds or mammals or cause damage to public or private property.  The owner shall reimburse the department for all costs incurred in capturing or removing the mammals from the wild.  The owner of the mammals shall be responsible for any damage they may cause to public or private property.

Any domesticated big game mammal may be marked with ear tags or other suitable markings or tags, as may be specified by the commission, which shall identify the owner of the mammals.