If topic creators move their thread, you see something like this:
This topic has been moved to [BOARD].
[TOPIC LINK]
If it's the admin/mods, you won't see a trace.
Not exactly right, mods/admins have the choice to leave a redirection topic or not when they move a topic.
Look at this topic:
https://bitcointalk.org/index.php?topic=5243762.msg54305615#msg54305615.
At the beginning I let redirections, but it was polluting a bit. And when a mod/admin leaves a redirection topic, he becomes the owner of that topic (not really constructive, I didn't want to give more work to the CM

).