Roud #39311 is "St. Brendan and the Albatross." There is no other mention of "Brendan" in either the Roud Index or the Traditional Ballad Index, except in place and performer names. There are recordings of "St. Brendan and the Albatross" on YouTube. I personally doubt that it is really traditional.

Given that St. Brendan, even if you accept the legends of his life, lived before the English language could really be said to exist, I don't think you'll find anything else in English. Maybe in Irish. But, even there, I would expect it to be literary.