Exporters and shipping companies are not the only ones profiting from growing business and trade between Nigeria and the rest of the world.

Pirate entrepreneurs have also discovered the increased opportunities and have revved up their activities in and around the Gulf of Guinea.

That increase in activity cost container shipping giant Maersk Line 1.1 billion kroner last year as it spent more on training and equipment designed to deter pirate attacks. That is double the amount the company spent on anti-piracy in 2010.

In 2011, there were 64 reported incidents of piracy in the west African region versus 46 the year before, according to the UN. The international organisation notes, however, that many incidents and thwarted attempts go unreported.

The rising market in piracy is one trend that Maersk executives are following with rapt attention.

“There are a couple of regions that we are watching very closely,” Maersk Line supervisor Erik Rabjerg Nielsen told the Wall Street Journal. “We are experiencing armed attacks and they have escalated recently.”

Nielsen's observation was backed up by maritime analysts at AKE Group, a risk consultancy.

"The risks off Nigeria are increasing because of an increase in militancy in the Delta region," Rory Lamrock, a maritime analyst at AKE Group, told the Wall Street Journal.

Nielsen believes Maersk Line will have to spend even more on deterrence and protection in 2012, if the piracy trend continues.