A team would earn 500 points by tagging and releasing their catch or, should they want to keep their fish, teams would multiply the fish's weight by 100 and then divide it by their line class to see how many points they were awarded.
Johnson said this promoted sustainable fishing because most teams would opt to release their fish, unless they had caught something particularly heavy on a lighter line.
"We hope the points system encourages anglers to release the fish, but we've already had three of four fish weighed in this year over 300kg so there's definitely big fish around."
Last year's winners reeled in and released eight marlin as well as weighing a blue marlin, which came in at over 600 pounds (270kg). Johnson said this was the standard teams needed to meet to come out on top.
"Most Kiwi anglers are pretty happy if they even see a marlin on a day out game fishing and to be in the money for the tournament you've got to be up there and be catching two or three a day and some pretty big ones as well."
He said while the tournament was a competitive one, the small numbers of boats meant there was a strong sense of camaraderie within the field.
"If you had a hundred boats out there, no one would talk to each other but with a smaller number, each night boats will raft up and get together which is great to see."
For competition updates, go to the Bay of Island Swordfish Club Facebook page for daily, midday catch reports.