Yay, Qiraji Guardling collected! The last of the wild pets is now in my pet army, so I'm all set until they release more wild ones.
I ended up getting the guardling on an alt on a PVE server. With the addition of spectate mode (not optional), it removed the ability to battle while stealthed or shadowmelded. This means trying to catch a highly desirable wild pet on a PVP server is just suicide. I've seen the battles between players over a wild pet; no one wins in that situation, as the pet is often a casualty of war. So I wasn't taking any chances!
There were quite a few other players on the PVE server by the time I logged in. No one was sure if the pets would start spawning midnight server time or midnight PST. Turns out it was the latter, so many people were waiting an extra long time.
I made a beeline straight for the first one I saw, but there seemed to be plenty of spawns to go around. At least I think there were. I saw a few others battling once I had finished my own match, so hopefully others managed to capture a guardling too. :)
Anyway, I'm now a proud "Zookeeper" although I don't think I'll be using the title much. Whenever I think of a zookeeper, large piles of animal waste comes to mind. :P