Bob Roberts had a version of this. He called it the Yarmouth Shanty, though clearly it is a net hauling song rather than a shanty. He published it in EITHER Slice of Suffolk OR Breeze for a Bargeman. Unfortunately due to a recent move my copies are boxed up and I can't check
From memory the missing lines are:

We who plough the North Sea deep
We never sow, we always reap

We reap the harvest of the sea
And Gorlestone Light is home to me

Heave her up and heave her down
And heave her back to Yarmouth Town

Joskins were the leather overtrousers that farm workers wore at harvest time to protect their legs against being cut nby the schyle or sickle. In winter when there was litle work to do on farms many agricultural labourers were laid off, and in order to earn a little money they worked on the fishing boats. Since they had no desire to do this long term they rarely went to the expense of buying proper oilskin trousers - they just wore their joskins. Real fishermen therefore referred to these part-time bumpkin sailors as Joskins.