The Iberian wolf, Canis lupus signatus, was hunted to the point of near extinction by the 1960s but thanks to conservation efforts has made a comeback over recent decades.
More than 2,000 animals form at least 250 distinct packs now roam the Spanish countryside and have even reached as far south as the Sierra Norte, a mountain range within 100km of Madrid.
But farmers are not always happy about the conservation efforts, which have led to a huge rise in attacks on livestock. Between 2011 and 2015, farmers made a total of 14,500 separate applications for compensation for livestock killed by wolves in Asturias alone.
Although they are a protected species in certain parts of northern Spain they can be hunted with the correct licence. For 2016, local authorities in Asturias have given permission to cull 45 wolves in the region.
However, Spain's Civil Guard are concerned at a spate of recent killings of wolves, whose heads have been decapitated and left on display around Asturias. They have appealed to the public for information that could lead to the wildlife killers.
The Association of forest rangers of Asturias (Avispa) believes that the wolf decapitations are "revenge attacks" designed to challenge the authorities stance on wolf management, a spokesman told the La Voz de Asturias.