World of Warcraft Quests involving Northspring Harpy:
Alliance & Horde
Screecher Spirits - (Step 1) Capture the spirits of 3 screechers in Feralas, then return to Yeh'kinya in Steamwheedle Port.
Vengeance on the Northspring Talo Thornhoof wants you to kill 4 Northspring Harpies, 4 Northspring Roguefeathers, 4 Northspring Windcallers, and 4 Northspring Slayers.
Maraudon Horde Quest
Vyletongue Corruption (Horde) Fill the Coated Cerulean Vial at the orange crystal pool in Maraudon.
Use the Filled Cerulean Vial on the Vylestem Vines to force the corrupted Noxxious Scion to emerge.
Heal 8 plants by killing these Noxxious Scion, then return to Vark Battlescar in Shadowprey Village.