Musannaf Ibn Abi Shayba 1:1378

Abu Bakr narrated to us, he said: Abd al-Rahim ibn Sulayman narrated to us, from Yahya ibn Sa’id, from Abdullah ibn al-Mughirah, from a man of Banu Mudlij, that he asked the Messenger of Allah (may Allah bless him and grant him peace). He said: "O Messenger of Allah, we ride rafts upon the sea for fishing, and we carry water with us for drinking. When the time for prayer arrives, if one of us performs ablution with his water, he becomes thirsty, and if he performs ablution with the water of the sea, he finds [a hesitation] within himself." He claimed that the Messenger of Allah (may Allah bless him and grant him peace) said: "Its water is purifying, and its dead [creatures] are lawful."