Hi Graham , supposedly a former Portuguese Oceanographic survey ship, she was bought by the Spanish Government in 1993 and transferred to the Spanish Customs service, the 'Aduanas'.
Aduanas =Customs/Excise.
This ship patrols the North/Mid Atlantic & off West Africa, and has had some spectacular drug seizures from drug running yachts, ex fishing boats and the like, sailing across the Atlantic from the Caribbean and the Americas. The busts are always widely reported in the local Press.
Regards, Rick