Amid a tight supply and demand situation, prices for private maritime security guards onboard have shot up dramatically this year, rekindling the era of Somalian piracy more than a decade ago.

The disruption brought about by the Houthis’ campaign to target more than 70 merchant ships over the past five months has seen traffic slump by more than two-thirds in the Red Sea, but for vessels heading to the region armed guards have become necessary.

The demand for extra security has also been b...