GULF OF GUINEA

However, piracy is on the increase on the other side of Africa in the Gulf of Guinea, an increasingly important source of oil, cocoa and metals - and where international navies are not actively engaged in counter-piracy missions at present.

"There has been increase in the overall severity of attacks. Last year, most attacks were low level, smash and grab type robberies in ports and anchorages," said Rory Lamrock, an intelligence analyst with security firm AKE.

"Now, we're seeing more abductions of sailors from oilfield supply vessels off Nigeria, and tankers being hijacked as far west as Abidjan. This type of violent maritime criminality shows no sign of decreasing any time soon."  

The IMB said there were 58 incidents recorded in 2012 in the Gulf of Guinea, including 10 hijackings and 207 crew members taken hostage, with violent attacks common and guns used in at least 37 of the incidents.

That compared with 46 incidents in 2011. Last year, 26 seafarers were kidnapped for ransom in Nigeria, a rise from 17 taken in 2010 and none reported in 2011.    

The number of crew members held hostage globally fell to 585 from 802 seafarers held in 2011. Of the total, Somali pirates took 250 hostage last year - with 104 crew members still being held at year end, the IMB said.

"IMB's piracy figures show a welcome reduction in hijackings and attacks to ships. But crews must remain vigilant, particularly in the highly dangerous waters off east and west Africa," Mukundan said.