They are in the sea as well

They are in the sea as well as on land. That is well known by those that are out fishing by the coast. When the weather is calm, they can look down sometimes and see cattle and pigs and all such things as we have ourselves. And at nights their boats come out and can be seen fishing,but they never last out after one o'clock.

... There are more of them in the sea than on the leand, and they sometimes try to come over the side of the boat in the form of fishes, for they can take their own choice shape.

-- A fisherman on Kilroanan Pier, in Lady Gregory's Visions and Beliefs in the West of Ireland, 1920