Lyrics are
Ionn da ionn do
Ionn da odar da
Hi-o-dan dao x3
odar da.
The song is called The Seal-Woman's Sea-Joy.
A traditional seal song, collected at least 70 years ago in the Hebrides and given by Kenneth MacLeod in Songs of the Hebrides, Vol 1.
Margaret Kenndy-Fraser used this song to attract the attention of the seals. I prefer to use the Tigh nurru nigh nura nigh roe song (I don't have the Gaelic spelling for it) which Jean Redpath sings.
For more wonderful tales, songs and information see the book The People of the Sea by David Thomson.