Musnad Ahmad 27:683

Muhammad ibn Ja'far narrated to us, Shu'bah narrated to us, from 'Abdullah ibn Dinar, [who said]: I heard Ibn 'Umar narrating that the Messenger of Allah (peace and blessings of Allah be upon him) said: "There is no sin upon the one in the state of ihram for killing five [creatures]: the biting dog, the crow, the kite, the mouse, and the snake."