Fishing in a very different way

Spotted on my bike ride over the Medieval stone bridge over the Tweed to Berwick.
Salmon fishermen set up a winch on one of the tidal islets in the river then spread a net across to the northern shore with a rowing boat, wait awhile and use a hand powered winch to pull the net in, and they caught...
Absolutely nothing!
And that was after Four attempts, before the island completely flooded
Ah well better luck tomorrow perhaps?