Activity patterns in the reintroduced Pyrenean brown bear population

Abstract

Mammals usually adjust behavioral patterns when exposed to disturbances. Elusiveness and low-risk time selection may reduce their stress in periods of highest risk. In Europe, brown bears (Ursus arctos) coexist with humans in densely populated and modified landscapes and, consequently, are exposed to human-caused disturbances during the daytime hours. Furthermore, intraspecific interactions might also influence their behavioral responses, especially during the mating season. Activity patterns of several large carnivores have been thoroughly studied; however, research is scarce for relocated populations. Here, we report the activity patterns in the reintroduced brown bear population in the Pyrenees. We expected the bears to reduce their activity depending on the type and level of disturbances. We analyzed individual behavior of both sexes (males, solitary females, and females with offspring) and age groups (adults and subadults) using camera-trap surveys under different types of intraspecific and anthropogenic disturbances. In general, bears were more active during the night (2200–0600 h) and avoided peaks of human activity (1000–1800 h). Furthermore, with the increasing nocturnal disturbance of adult males during the mating season, females with offspring and subadults were more active during daylight. This suggests that vulnerable individuals showed high tolerance for human presence. These results contribute to improve our knowledge of how a threatened and relocated bear population behaves in a human-modified landscape of southern Europe. Further research on this population will be crucial to establish optimal management interventions during translocations, and the prevention of human-bear encounters and conflicts.

Seasonal and diel movement patterns of brown bears in a population in southeastern Europe

“…Females with dependent offspring showed a contrasting movement pattern compared with other reproductive classes, with movement occurring predominantly during daylight (mating season) and crepuscular hours (hyperphagia season). This is in line with other studies showing that females with offspring are more diurnal than other reproductive classes (Kaczensky et al, 2006;Munro et al, 2006;Parres et al, 2020;Rauer et al, 2003;. During the mating season, adult males may kill cubs of the year , and females with cubs try to avoid infanticide by shifting their movement into daytime hours (Dahle & Swenson, 2003;Edwards et al, 2013;Wielgus & Bunnell, 1995).…”

“…Both classes had movement peaks at similar times of the day (Figure 2). A comparable pattern was also found in adult males and solitary females in the Pyrenean brown bear population during spring, which coincides with the mating season (Parres et al, 2020). Diurnal movement in adult bears in our study areas was very low during both seasons, which corresponds to the results obtained for adult bears in Slovenia and Croatia (Kaczensky et al, 2006).…”

“…Although natural food resources are often widely dispersed , artificial feeding sites can provide a clumped, high-calorie food sources which can alter bear movement patterns (Kavčič et al, 2013;Selva et al, 2017;Ziegltrum & Nolte, 1997). Also, humans greatly affect bear behavior and life history Ordiz et al, 2014;Van de Walle et al, 2018;Zedrosser et al, 2011), and bears generally try to avoid humans on a spatio-temporal scale, that is, bears move mostly during night and crepuscular hours when human activity on the landscape is lower (Kaczensky et al, 2006;Ordiz et al, 2014;Parres et al, 2020;Roth, 1980;Roth & Huber, 1986).…”

“…The main aim of this study was to evaluate the differences in seasonal and diel movement patterns for different reproductive classes of brown bears in a human-dominated landscape and area of great conservation concern. Based on existing literature of diel movement patterns of brown bears in human-dominated landscapes (Ćirović et al, 2015;Hertel et al, 2017;Kaczensky et al, 2006;Parres et al, 2020), we predicted (i) that bears would follow a bimodal movement pattern with periods of high movement during crepuscular hours and that (ii) bears would move over longer distances during the mating than during the hyperphagia season. We further predicted that (iii) dispersing subadult males would travel longer distances during the mating season than adults and females with dependent offspring and that (iv) differences in movement patterns between reproductive classes would be less pronounced during the hyperphagia than during the mating season.…”

“…Although natural food resources are often widely dispersed (Hertel, Steyaert, et al, 2016 ), artificial feeding sites can provide a clumped, high‐calorie food sources which can alter bear movement patterns (Kavčič et al, 2013 ; Selva et al, 2017 ; Ziegltrum & Nolte, 1997 ). Also, humans greatly affect bear behavior and life history (Hertel, Zedrosser, et al, 2016 ; Ordiz et al, 2014 ; Van de Walle et al, 2018 ; Zedrosser et al, 2011 ), and bears generally try to avoid humans on a spatio‐temporal scale, that is, bears move mostly during night and crepuscular hours when human activity on the landscape is lower (Kaczensky et al, 2006 ; Ordiz et al, 2014 ; Parres et al, 2020 ; Roth, 1980 ; Roth & Huber, 1986 ). Therefore, sustainable bear conservation and management must take into consideration the natural patterns of bear movement as well as the behavioral responses to human disturbance (Hertel et al, 2017 ; Tuomainen & Candolin, 2011 ; Zarzo‐Arias et al, 2018 ).…”