A number of wild pets are seasonal, weather or time-dependent so check this out if you’re missing a few.
Unborn Val’kyr – there is always one spawn up in each zone of Northrend
Arctic Fox Kit – The Storm Peaks – snowing
Baby Ape – Jaguero Isle, The Cape of Stranglethorn – raining
Silithid Hatchling can be found at the Gaping Chasm / Noxious Lair, Tanaris – sandstorm
Restless Shadeling can be found around the cellar in Deadwind Pass (midnight and 9 AM, server time)
Shadow Sporebat – Khadgar’s Tower, Talador
Stone Armadillo can be found in Desolace at night (server time)
Widow Spiderling can be found near the Twilight Grove, Duskwood – night
Erudite Manafiend – Ley-Ruins of Zarkhenar in Azsuna – day
Eldritch Manafiend – Ley-Ruins of Zarkhenar, Azsuna – night
Qiraji Guardling – found near The Scarab Wall and The Scarab Dais in the southwest area of Silithus – Summer (21 June – September 23)
Snowy Owl can be found in Winterspring – Winter (December 22 – March 19).
Wanderer’s Festival Hatchling can be found at Turtle Beach in Krasarang Wilds during the Wanderer’s Festival – every Sunday from 9:00pm to 11:00pm (check post for other timezones) or Monday 4pm – 6pm on Oceanic servers
Crow can be found at Darkmoon Island ONLY as a secondary pet
Darkmoon Glowfly can be found on Darkmoon Island
Wild Crimson, Jade, and Golden Hatchlings can be found in The Arboretum in the Jade Forest once you’re exalted with the Order of the Cloud Serpent.
There’s also a video of all these pets and locations.