A YouTube user named DukhaTsaatan has posted several videos recorded of old Mongolian documentaries about the Tsaatan reindeer herders. Or at least he thinks they are. The earliest, from 1959, shows people collecting fish and transporting them on sleds pulled by reindeer, then some people riding reindeer toward the end. They don't look like the Tsaatan from that time shown in these photos. I'm not sure the Tsaatan are the only people in northern Mongolia who would use reindeer in the winter, though they may be. It looks to me like the film might be about a fishing collective. In 1959, the Mongolia government was probably eager to advertise their recent successes with collectivization. It would help if I understood Mongolian.