Hey there, just wanted to share the info I got today on the Silithid Hatchling that's part of the Zookeeper's title;
Today from 12:00 till 14:55 I witnessed a Sandstorm in Tanaris. I was circling around in the Chasm with one account and in the Lair with my other account.
After 2 hours I hadn't seen 1 hatchling, so I decided to open up a ticket and after the best and funnyiest talk I ever had with a GM in 7 years he told me that there seems to be a BUG with the weather dependant pets at the moment, they seem to only spawn when the wheather "spawns".
His advice was to be either lucky enough to be there right away when it spawns, make a few circles and then just leave it alone.
TL;DR; There's a bug with them, they only spawn when the sandstorm starts.
Here's the screenshot I took from the funny chat I had with the GM, worth to read imo
http://equinoxguild.eu/gm-chat-silithid-hatchling.jpg