There was a time in the olden days when the cormorant and the bat took counsel together to do something for the poor as they had compassion on them, and they went into the glens gathering wool to make clothing for them.
When they had a quantity gathered they took a boat and put out to sea. It happened as they were sailing that a storm came on and the waves were breaking over the vessel; the poor bat had to leap from place to place to escape the water, and in the darkness he was cast out of the boat clinging to an oar.
At daybreak he was near the shore and flew unto dry land. A seagull, standing near by enquired :
“Och, li’l bat, what’s there doin’ on thee that thou are all of a thriddle of thrimblin’ like this?” When the seagull heard the bat’s story, he said, “As sure as can be, if he will happen on thee, he will take thy life.” For the cormorant and the bat had given each other a promise that one would not leave the other until they had completed their task.
The bat was so frightened that he hid himself in an old ruin until the darkness came on and from that time until now he will only venture out under covering of the night.
The cormorant held on to the boat until she filled with water and sank to the bottom of the sea. At last he flew to a rock and there sat for hours, day after day, looking out for the bat. At other times he would go for a season into the glens; and in this way they continue from that storm to the present time – the one hides himself, and the other seeks him.
(source: Manx Fairy Tales by Sophia Morrison (1911); bat photograph by Tim Flach; cormorant photograph from wiki)