Purse Seine Fishing
Commercial fishing boats galore greeted us on our arrival to Majuro, Republic of the Marshall Islands.
Here is a brief summary of how these big fishing ships do their work.
First, locate a school of tuna with you helicopter or by observing bird flocks.
Take the ship to the school of fish and launch the tender which is basically a floating 5000hp diesel engine and propeller. Pull the net around the school of fish while the ship goes around the school the other way. The idea is to form a circular curtain of net around the school. Nets are many hundreds of meters long laid very carefully on the aft deck.
Once the tender and ship meet up again, secure the loose end of the net to the ship (purse with no bottom) and then tighten the rope at the bottom of the curtain to form a purse with a bottom. Voila. 25 000 fish in a bag.
Tighten the rope on the top to make the purse smaller. Then once it is alongside start scooping up the fish. The scooping nets are 10m across and attached to large winches. Drop into the purse, scoop up a hundred fish, deposit on fishing ship for gutting and freezing. Repeat as necessary 24/7 to fill the ship. No, they don’t come back until they are full!