This Power Block is attached to this truck on a boom. The power block is hydraulically powered to rotate and pull the net up and over the rail of the boat. This type of work used to be done by hand.
Once offloaded the net can be transported by truck to an open space where it can be stretched out and worked on.
Another technological advance which lends marine work to not need to have such a wide footprint on a harbor. That space that used to be needed along waterfronts to repair nets can now be done in covered buildings in industrial parks like Swan Net does up at The Blackburn Industrial Park in Gloucester.