A blue feather is a drop from the Cerulean twitch bird caught using the Hunter skill. Level 11 Hunting and at least one bird snare are needed to catch these birds in the Rellekka Hunter area.
Blue feathers, along with all coloured feathers gathered from the Hunter skill, can be used in place of regular white feathers with the Fletching skill. Despite the difference, the arrows still come out with white feathers and are used as normal arrows. They can be sold at the Varrock Fancy Dress Shop for 9 coins each. They can be used for fly fishing.
A blue coloured feather headdress can be created by adding 20 blue feathers to a leather coif with 79 crafting.
Completing the Court Case "Ernest vs Professor Oddenstein" rewards the player with 15 red, blue, and yellow feathers.
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