Somaliaonce a hotbed of piratical unrestis quickly losing its title to Nigeria. This year more than three times as many pirate attacks have occurred in the Gulf of Guinea, off West Africa, as in the waters around Somalia on the eastern coast. A new report (pdf) published today by the International Maritime Burea, Oceans Beyond Oceans, and Maritime Piracy Humanitarian Response Programme shows that piracy is on the rise in waters off the coasts of Nigeria, Benin, Togo, Ghana, and Cote d’Ivoiregenerally with Nigerian attackersand the attacks often prove more violent. Of 120 attacks reported so far in 2013, 22 were Nigeria-related incidents while only 7 were Somalia-related incidents.

That’s a rapid pivot from last year, when, as we’ve previously reported, pirate attacks off East Africa, despite having fallen sharply, were still more common than off West Africa.

Seafarers are particularly vulnerable in West Africa because they’re often stalled, either at sea or or in port. According to the IMB, port security guards aren’t reliable because they know that their weapons don’t match up to those of would-be pirates or robbers. Pirates are often ex-members of militant groups, and are well-armed. And while international security forces like the US navy, the EU, and NATO have built up presences in Somali thoroughfares, authorities in the Gulf of Guinea are notoriously unreliable, and occasionally are even thieves themselves.

Though not all pirates do it, West African raiders make the most money from selling oil in oil tankers that move to and from oil-rich countries on the Guinean gulf. This is a change in tactics from the old ransom model favored by the Somalis. “In the course of their attacks, West African pirates steal refined petroleum products estimated to be worth between $2 million and $6 million on average, with values reaching as high as $10 million, the report says. “With seven incidents of oil theft reported, the value of stolen petroleum in 2012 is estimated to have been between $14 million and $42 million [emphasis ours].

Unsurprisingly, international organizations are bulking up security forces in the region. The US, UK, Australia, and various EU member states have pledged funds to help local governments improve security. Shippers are paying more money to better arm and insure their vessels. Relying on local authorities is a bit of a wild card; West African countries pressed precisely zero court cases against pirates in 2012. But if the Somali experience is any example, international efforts to ramp up the forces against piracy will probably discourage pirates from attacking all but the most vulnerable vessels.