Title: Movement of skipjack (Katsuwonus pelamis) tuna in the archipelagic waters and exclusive economic zone of Papua New Guinea.

Skipjack tuna dominates the purse-seine catch in Papua New Guinea. The fisheries in the archipelagic waters and exclusive economic zone are currently managed as a single entity. However, because of the huge land mass and abundance of food sources provided by the large river deltas that flow into the Bismarck Sea, the question of whether there is a larger resident population of skipjack that occurs in archipelagic seas has arisen. Therefore, the movement of skipjack tuna in the Archipelagic Waters (AW) and the Exclusive Economic Zone (EEZ) of PNG is explored to deduce whether a considerable amount of stock resides in the Archipelagic waters. Conventional tagging data from the PTTP and observer sampling data were used to study 1) the extent of skipjack tuna movement between Archipelagic Waters and Exclusive Economic Zone, 2) to analyze any size difference of skipjack tuna from AW and EEZ waters. This study showed results where most fish released from central part of the PNG AW were recaptured close by within 0 -250 days at liberty. It is evident that based on where the fish are tagged and released the proportion recaptured in the AW versus the EEZ can differ however, this study only analyzes locations of release and recapture and does not track the path of individual fish. Therefore, it is difficult to conclude that these fish reside in the AW during their entire days at liberty. Given the high migration speed of tuna, fish could be travelling out to the EEZ in the interim period and migrating back to AW. It is recommended that a home range analysis can be done to delineate the home range or habitat of the species and the use of archival tags for further studies is also recommended for better understanding of movement patterns. Finally, to better the residence times of fish, advection-diffusion reaction models can be applied for future work.