Genetic monitoring of wolves in Romania's Southern Carpathians shows decrease in population

The wolf monitoring program, initiated in 2017, was carried out across six hunting grounds in the Făgăraș, Iezer-Păpușa, and Leaota Mountains and the territory of Piatra Craiului National Park, Romania.

Perhaps the most important finding regarded population density. In the winter of 2024–2025, it was estimated at approximately 1.46 wolves per 100 sq km, compared with 2.35 in the winter of 2019–2020.

At the same time, the number of identified individuals decreased, while packs were more numerous but smaller. Taken together, these data may indicate the loss of some mature and experienced individuals from the population, although it is not yet known whether this has natural or anthropogenic causes.

The effects of such instability are difficult to anticipate. The loss of experienced individuals and frequent changes in pack structure may increase the risk of interactions between wolves and humans.

Young wolves, less experienced in hunting, as well as packs undergoing reorganization, may seek new territories and more easily accessible food sources. Studies conducted in other regions show that high wolf mortality, including through hunting or poaching, can destabilize pack structure and increase the risk of attacks on domestic animals.

Monitoring was based on non-invasive methods, through DNA analysis of biological samples collected in the field, such as urine on snow, feces, and hair.

The analyses allowed the identification of individuals, population estimates, reconstruction of kinship relationships, and approximation of the territories used by different families, and showed how the population is organized and changes over time.

In the 2024–2025 season, field teams collected 259 DNA samples, bringing the total to 1,100 samples over the past seven years, a unique monitoring effort in this part of Europe. Overall, 24 wolves – 10 females and 14 males – were identified over an area of approximately 1,400 sq km. The data provided a clearer picture of the relationships between individuals, pack dynamics, and how wolves use territories.

This shows that, despite reduced social stability, the Southern Carpathian landscape is still sufficiently connected to allow wolves to make long-distance movements and natural genetic exchange between packs. Wolves can travel an average of approximately 20 kilometers per day, while annual movements can sometimes exceed 1,000 kilometers.

Another important result of the genetic analyses concerned hybridization between wolves and dogs. In 2019, such a case was documented in the project area, but no cases of hybridization have been identified in recent analyses, which is a positive signal for the genetic health of the wolf population in this area.