Determinants and patterns of habitat use by the brown bear Ursus arctos in the French Pyrenees revealed by occupancy modelling

Abstract

The Pyrenean brown bear Ursus arctos population in the mountains between France and Spain is one of the smallest and most threatened populations of large carnivores in Europe. We assessed trends in brown bear habitat use in the Pyrenees and investigated the underlying environmental and anthropogenic drivers. Using detection/non-detection data collected during 2008–2014 through non-invasive methods, we developed dynamic occupancy models, accounting for local colonization and extinction processes. We found two non-connected core areas of occupancy, one in the west and the other in the centre of the Pyrenees, with a significant decrease in habitat use overall during 2008–2014. We also found a negative correlation between human density and bear occupancy, in agreement with previous studies on brown bear habitat suitability. Our results confirm the Critically Endangered status of the Pyrenean population of brown bears.

Identifying habitat use of Ursus arctos, Lynx lynx martinoi and Canis lupus lupus in Albanian forests using occupancy modelling

“…The data resolution of this study was 1 km 2 . Assumptions on relationships between species colonization probability and predictor variables are based on the literature and knowledge of biology for brown bear (Piédallu et al 2019), lynx (Molinari-Jobin et al 2017;Melovski et al 2018) and wolf (Louvrier et al 2017) in Europe (see 2.3 Model selection). ψ 1 = initial occupancy probability γ = colonization probability, ε = local extinction probability, and p = detection probability, Y = year, 7 = forest cover in 2000, 8 = forest cover in 2010.…”

“…Occupancy models were built-in for the three large carnivore species, focusing on time-varying natural conditions and resources predictor variables representing forest cover for 2000 and 2010, and 2001 and 2011 for three large carnivore species, and site-varying variables. Sitevarying predictor variables were elevation, terrain ruggedness index, shrub cover (Piédallu et al 2019) (Louvrier et al 2017) and wolf neighbouring grid cells were the site-varying predictor variables for wolf. Site-varying human disturbance predictor variables were distance to nearest neighbourhood roads and cultivated land for the three large carnivore species (Louvrier et al 2017;Molinari-Jobin et al 2017;Piédallu et al 2019).…”

“…Dynamic occupancy models (and occupancy models in general) make it possible specifically to account for the effect of local processes of colonization and local extinction on the species range dynamics (MacKenzie et al 2003). Dynamic occupancy models have been successfully used to identify environmental or anthropogenic drivers in habitat use by brown bear in the French Pyrenees (Piédallu et al 2019), to explain wolf recolonization in France (Louvrier et al 2017) and to evaluate Eurasian lynx populations in the European Alps (Molinari-Jobin et al 2017).…”

Challenges for recovery of large carnivores in humanized countries: attitudes and knowledge of sheep farmers towards brown bear in Western Pyrenees, Spain

“…In recent years, human dimensions have been explored across different bear populations in Europe, from large to small, or from recovering to reintroduced populations (e.g., Majić et al 2011;Dressel et al 2014;Glikman et al 2019;Piédallu et al 2016bPiédallu et al , 2019Hovardas 2018). Still, there is a lack of information in those scenarios where the size of remnant large carnivore populations is very small and close to extirpation, such as the case of bears in the Western Pyrenees.…”

Habitat use and selection patterns inform habitat conservation priorities of an endangered large carnivore in southern Europe

“…Mediterranean region), with its distinct environmental conditions and high anthropogenic pressures, is still incomplete (but see e.g. Mertzanis et al 2008, Piédallu et al 2019. In addition, rear-edge populations (i.e.…”