In the case of yellowfin and bigeye stocks, fishing mortality from gillnet and longline gears (28% and 15% of catches in 2010; [27]) is expected to increase as socio-political conditions in the Indian Ocean change. Increasing pirate activity in the northwest Indian Ocean during the mid 2000s displaced fishing activity, particularly the longline fleet, into other parts of the Indian Ocean [26] and [9], but attempts to control this threat (e.g. NATO counter-piracy operations, private security personnel etc.) has already allowed some of this fleet to return to the western Indian Ocean in 2013 (Seychelles Fishing Authority, pers. comm.). As the threat of piracy is reduced in future years, the presence of longline and gillnet vessels in the western Indian Ocean might be expected to increase further, leading to a significant increase in fishing pressure on stocks of yellowfin and bigeye tuna.