may Allah be pleased with him:

“Some people came to the Prophet, peace and blessings be upon him, and said: ‘We travel far out to sea, carrying only one or two waterskins of water, for we do not find game until we have gone far away. May we perform ablution with seawater?’ He said: ‘Yes. Its water is purifying, and its dead creatures are lawful.’”

From the jurisprudence of the hadith:

The hadith contains an important benefit: everything that dies in the sea, provided that it lived therein, is lawful, even if it floats upon the water. How excellent is what has been narrated from Ibn Umar: he was asked, “May I eat what floats upon the water?” He replied, “What floats upon it is among its dead creatures, and the Messenger of Allah, peace and blessings be upon him, said: ‘Its water is purifying, and its dead creatures are lawful.’”

Al-Daraqutni narrated it (538). The hadith prohibiting the eating of what floats upon its water is not authentic, as explained elsewhere.

481 — “The Hour will not come until people copulate in the road as donkeys copulate.” I said, “Will that truly happen?” He said, “Yes, it most certainly will.”

Al-Bazzar recorded it in his Musnad (p. 238, Maktab photocopy edition): Muhammad ibn Abd al-Rahim narrated to us; Affan narrated to us. Ibn Hibban also recorded it in his Sahih (1889, Mawarid): Ahmad ibn Ali ibn al-Muthanna informed us; Ibrahim ibn Hajjaj al-Sami narrated to us. Both said: Abd al-Wahid ibn Ziyad narrated to us; Uthman ibn Hakim narrated to us; Abu Umamah ibn Sahl ibn Hunayf narrated to us, from Abd Allah ibn Amr, who said: The Messenger of Allah, peace and blessings be upon him, said—and he mentioned it.

Al-Bazzar said: “We know of no authentic route for it except this one.”