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Drift gillnets are commonly used in Pakistan for the catch of Tuna and tuna like species. Their operations range from coastal to offshore areas while there is little information on the fishing operations in the high seas or areas beyond national jurisdiction. Around 700 driftnet gillnet (multifilament) vessels operate exclusively for the catch of tuna and tuna like species in the Arabian Sea adjoining Pakistan. There is relatively new information available from Pakistan from the tuna driftnet gillnet fisheries on the target and non-target catches from recent years, however, in some and most cases, species composition data is not available for the bycatch caught. Furthermore, the Pakistani drift gillnets have also been using different gear settings/fishing methods (surface and subsurface) and its preliminary results show promising results for the decline of bycatch for some species. Therefore, in order to better understand the nature of bycatch and its composition, this paper is aimed to provide an in-depth analysis of the bycatch and species composition data by taxon and by fishing method. This data has been collected from January 2013 – December 2017, during this period 3,874 drift gillnet sets were observed. A total of 443,458 catches were reported which included nine taxons, viz. tunas (68.8%), other teleost’s (29.4%), selachii (1.6%), mobulids (0.004%), batoids (0.01%), cetaceans (0.04%), sea turtles (0.14%), reptiles (0.0006%) and invertebrates (0.03%). We focused on tropical tuna as the target catch and considered all other catches as bycatch from the fishery. Capture rates (CPUE) were calculated for each taxon and on the basis of gear settings/fishing method, i.e. surface and sub-surface. The analysis revealed and further confirmed that there were no significant changes in the catch of target species (tropical tunas), while numbers seemed to decrease, there is a higher yield in sub-surface gear settings. The results from the analysis also continue to show positive impact on incidentally caught species, with lower CPUE in subsurface (3.51) as compared to surface gear settings (6.00). Furthermore, CPUE values for sharks (X-squared = 389.99, p < 0.001) was also compared with target catch (X-squared = 3.423, p > 0.05). Amongst the shark species, Rhizoprionodon acutus was the most dominant, followed by unidentified shark species, Isurus oxyrinchus and Carcharhinus falciformis, among others seven other species have also been reported. The results have been encouraging and while new information has been provided in this report, we recommend that alternate data collection systems, such as the use of crew as observers, if carefully handled could produce significant improvements in data deficient fisheries allowing to study species composition and fishing methods and may be coupled by electronic monitoring systems for triangulating the crew collected information. In addition, one of the most positive results of the analysis is the strengthening of our previous, that sub-surface fishing method/gear settings in tuna directed gillnet fisheries can provide positive trade-off among target and non-target catch, in particular reducing ecological impacts of gillnet/driftnet fisheries and may be considered as a potential conservation and management measure and data field to be considered by IOTC fisheries.