World Safari

Note these pets that you might have to wait for, either because of the time, the weather or the season isn't right:

Weather dependent

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• [npc=61324] - When it rains on Jaguero Isle. (Note: Jaguero Isle and Cape of Stranglethorn do not share weather. You have to go to the isle to see.)
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• [npc=62864] - Capturable when it snows in The Storm Peaks.
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• [npc=62258] - When there's a sandstorm in Tanaris.
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Time dependent

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• [npc=61375] - Appears at night right after 00:00 in a cellar outside of Karazhan.
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• [npc=62187] - Spawns at night. Around 7pm(?).
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• [npc=61259] - Found at night close to the Widow spiders in Duskwood.*
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Seasonal

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• [npc=62526] - Only surfaced during Warcraft summer.
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• [npc=7554] - Only surfaced during Warcraft winter.
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*I actually just came across a Widow Spiderling right now (14:00 server time) so I'm confused. It's listed as a "Night" pet, but 2pm is definitely not night. Anyone have an idea?

It will be at least 6 months after MoP release before you see anyone sporting this title. In Kalimdor, there are two seasonally dependent battle pets: the Snowy Owl in Winterspring and the Qiraji Guardian in Silithis. Because Pandaria launched just after the end of Warcraft summer, we have to wait for it to cycle around again before the Qiraji Guardians -- a summer-only pet -- are available.

In the meantime, don't forget to get a Snowy Owl while it's winter.

Currently, when you capture a pet that appears in more than one zone, it checks off the list for every zone. So you don't have to capture, say 20 different Snakes. Just one and it counts for every zone it appears in.