Brown bears (Ursus arctos) are the most widespread bear species in the world, with a distribution spanning Europe, Asia and North America.

Human persecution and habitat loss have led to the disappearance of brown bears from large parts of their original range. In Greece, the construction of large infrastructure projects, such as highways, poses a serious threat to the survival of the species.

Studying brown bears in Greece has relied until now on the recording of signs of presence and remote tracking of the species, methods that require significant scientific expertise and that are costly and time consuming.

However, brown bears love to mark and rub trees, a behaviour that is still poorly understood.

So in 2003, researchers of the Greek NGO ARCTUROS began recording intense marking and rubbing activity of bears on the power poles of the electricity and telephone network. In cooperation with partners a study was initiated to understand this behaviour.

Mud prints on the power poles give away the brown bears’ presence. These occur when bears lean against the poles in an effort to smell them.

Claw marks are present at most of the poles inspected.

However, the most prominent feature of bear activity around the power poles are the bite marks…

…in some cases bears chew through the poles, felling them.

Within the framework of the study, researchers of ARCTUROS placed a piece of barbed wire around more than 250 power poles in Greece in order to collect hair, which is then genetically analysed.

Infrared cameras are also used to understand this strange behaviour of the species.

Some of the bears are therefore more interested in the cameras than in the power poles.

Results from the genetic analysis indicate that marking and rubbing of bears on power poles is carried out mainly by males.

During rubbing on power poles, bears appear to prefer to rub their throat and chest against the pole.

More than 260 individuals have been identified so far through the monitoring of power poles in Greece, 215 of them just in the year 2008. This raises hopes that the population of the species in the country is higher than previously assumed.