| Sumario: | The large increase in human population and resource consumption in recent centuries has altered much of the land surface, negatively affecting the distribution and abundance of many species. Large carnivores are especially sensitive to these alterations due to their trophic position, which entails great energetic and spatial requirements. These requirements in a human-dominated landscape generate negative interactions with people that have resulted in the direct persecution of these species. This direct persecution, coupled with habitat loss and fragmentation, has brought many of their populations to the brink of extinction. The rise of social, political and scientific movements during the 20th century in favour of conservation prompted the creation of legal protection tools. The recovery of large carnivores was favoured by these measures, together with changes in land use resulting from the rural exodus, as well as environmental awareness policies. A good example is the brown bear in the Cantabrian mountains. At the end of the 20th century there were less than 100 individuals, separated into two genetically isolated subpopulations. By the 1980s the population stabilized and began to recover thanks to the legal protection of the species, the creation of protected areas in its habitat, public and private efforts in conservation and environmental education, and the rural abandonment. The demographic recovery of the Cantabrian population has been maintained up to the present day, as can be observed thanks to the census of females with cubs and the latest abundance estimates. However, this recovery is taking place in a human-dominated environment with limited optimal habitat. The main objective of this thesis is to analyse and describe the new challenges for conservation posed by the recovery of a brown bear population in a human-dominated landscape such as the Cantabrian mountains range. Chapter 2 evaluates the changes in the area of presence and breeding area of the population, showing a large expansion of the presence area towards territories with less human impact than those available. However, the breeding area hardly changes, probably because the optimal habitats for breeding are already occupied. This expansion does not translate into updated recovery plans, which could reduce surveillance in the new expansion areas, hinder the establishment of new breeding areas, and increase the risk of disturbance, mortality, and human-bear interactions. Chapter 3 analyses the spatiotemporal patterns of bear damage in the Cantabrian mountains. An increase in the abundance and distribution of damage over time is observed, with marked differences between damage types and subpopulations. The intensity of damage in each territory is influenced by demographic, environmental and spatial factors, but with great variability between types and subpopulations. However, the presence of spatial and temporal hotspots suggests that certain local characteristics, such as the high availability of resources, the absence of preventive measures or the behaviour of some individuals, are related to a greater number of damages. Chapter 4 provides the first systematic description and characterization of the events of bear presence in human settlements in the Cantabrian mountains. This is a relatively recent phenomenon, increasing in recent years and occurring mostly in the western subpopulation. These events have a marked seasonality, concentrating in summer during the fruiting of certain fruit trees, and are produced mainly by young individuals during the night. Villages with cases of bear presence are located in areas of high habitat quality, close to breeding areas, with a historical abundance of damage in their environment, and are close to other villages with cases. They tend to be closer to the forest, have rugged terrain around them, and have larger perimeters than villages without cases.
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