Request for origins, really.
This Mermaid Song is sung by Julie Murphy, we learned it at the Baring-Gould festival last October, but I'd like some background to it. Julie said in passing that it was American, but I didn't follow up on details at the time. Words as follows:

As I walked out one evening fair
Far out of sight of land
I spied a mermaid sitting on a rock
With a comb and a glass in her hand.

A combing down her gorse-coloured hair
Her eyes like a pale June sky
Her skin was as white as the ocean spray
Her voice wept a seagull's cry.

The song she sang, she sang so wild
No answer at all could I make
Till at length our ship she blew round about
Which made all our poor hearts ache.

This mermaid sprang back into the deep
The winds began to blow
Now the hail and the rain was so dark in the air
We'll never see the land no more.

Come take out your loads as fast as you can
The truth to you I tell
This night we all must depart
To heaven or else to hell.

Come all you folks that's living on the land
That's living at home at your ease
Try the best that you can your living for to gain
And never incline to the sea.

It has a haunting little tune. And i'm not v good with tadpoles.