2019-09-21: I recently revisited this post and attempted to recreate the plot using base R graphics, along with the mapplots and data.table packages for data manipulation.
On May 24-25, 2018, I attended the 9th WPEA-NSAP Tuna Catch Estimates Review Workshop in Ocean 101, Catangnan, General Luna (Siargao), Surigao del Norte.