Chicken

Chickens are background animals in Tomb Raider: Legend, and prey animals in the Survivor Timeline.

The are very timid and run away when Lara gets near them.

Tomb Raider: The Last Revelation
Chicken is on a barge that Lara lands her Jeep on, scaring it flying on top of the cabin.

Tomb Raider
In Tomb Raider, chickens can be found in the mountain village and shanty town.

Killing them provides XP, and with the Bone Collector Skill a small amount of Salvage.

Chickens along with rabbits must be killed and looted to unlock the "Tastes Like Chicken" Trophy/Achievement.

Rise of the Tomb Raider
In Rise of the Tomb Raider, chickens can be found throughout the Remnant village in the Geothermal valley. They provide feathers Lara can use to craft arrows.

Chickens are associated with one Trophy/Achievement, "Rotisserie", where Lara has to shoot a chicken out of the air with a fire arrow. There is also a challenge, "Fowl Play", in Geothermal Valley, to catch 5 chickens and throw them into the pen.

Shadow of the Tomb Raider
Chickens only appear in San Juan. Since it is a hub area where weapons are disabled, these chickens are just background animals, and can not be killed.

Tomb Raider: The Last Revelation

 * KV5 (cinematic)

Tomb Raider: Legend

 * Peru - Return to Paraíso

Tomb Raider

 * Mountain Village
 * Shanty Town

Rise of the Tomb Raider

 * Geothermal Valley
 * The Acropolis

Shadow of the Tomb Raider

 * Mission of San Juan