A brown bear has been sighted in a remote area of north-western Spain for what could be the first time in more than 150 years.

The animal was spotted by film makers shooting a movie called Montaña ou Morte (Mountain or Death) in the steep rocky landscapes of  the Invernadeiro national park in the Spanish autonomous province of Galicia. 

While there are small populations of brown bears in other parts of northern Spain, they have not been seen in this sparsely populated area of Galicia for more than a century.

"The bear, a male aged between three and five, is the first to be filmed in the area and probably the first to have crossed through the region in the past 150 years," according to the production company Zeitun Films. 

The animal was first captured by photo-trapping cameras the production team had spread over various locations in the area for two years to record the park's wildlife.

According to environmental agents from the Invernadeiro reserve, Ricardo Prieto Rocha and Tomas Perez Hernandez, the bear had likely spent the winter in the park, suggesting that years of conservation work has made the area suitable again as a habitat for brown bears.

Northern Spain is the historical home of the Cantabrian brown bear, but numbers dropped dramatically in the second half of the 20th century because of large-scale infrastructure projects and illegal hunting.

The species has been protected since 1973, but there are still only an estimated 350 brown bears living in the country today, according to the European Wilderness Society, one of the only two populations living in Central and Western Europe.

Video: Riaz Jugon