scholarly journals Infanticide as a male reproductive strategy has a nutritive risk effect in brown bears

2013 ◽  
Vol 9 (5) ◽  
pp. 20130624 ◽  
Author(s):  
S. M. J. G. Steyaert ◽  
C. Reusch ◽  
S. Brunberg ◽  
J. E. Swenson ◽  
K. Hackländer ◽  
...  
Keyword(s):  
Resource Selection ◽  
Ursus Arctos ◽  
Brown Bear ◽  
Mating Season ◽  
Predator Prey ◽  
Risk Effects ◽  
Risk Effect ◽  
Risk Period ◽  
Common Strategy ◽  
Spatio Temporal

Behavioural strategies to reduce predation risk can incur costs, which are often referred to as risk effects. A common strategy to avoid predation is spatio-temporal avoidance of predators, in which prey typically trade optimal resources for safety. Analogous with predator–prey theory, risk effects should also arise in species with sexually selected infanticide (SSI), in which females with dependent offspring avoid infanticidal males. SSI can be common in brown bear ( Ursus arctos ) populations and explains spatio-temporal segregation among reproductive classes. Here, we show that in a population with SSI, females with cubs-of-the-year had lower quality diets than conspecifics during the SSI high-risk period, the mating season. After the mating season, their diets were of similar quality to diets of their conspecifics. Our results suggest a nutritive risk effect of SSI, in which females with cubs-of-the-year alter their resource selection and trade optimal resources for offspring safety. Such risk effects can add to female costs of reproduction and may be widespread among species with SSI.

scholarly journals Human shields mediate sexual conflict in a top predator

2016 ◽  
Vol 283 (1833) ◽  
pp. 20160906 ◽  
Author(s):  
S. M. J. G. Steyaert ◽  
M. Leclerc ◽  
F. Pelletier ◽  
J. Kindberg ◽  
S. Brunberg ◽  
...  
Keyword(s):  
Habitat Selection ◽  
Sexual Conflict ◽  
Resource Selection ◽  
Ursus Arctos ◽  
Brown Bear ◽  
Offspring Survival ◽  
Adult Males ◽  
Predator Prey ◽  
Cascading Effects ◽  
Survival And Reproduction

Selecting the right habitat in a risky landscape is crucial for an individual's survival and reproduction. In predator–prey systems, prey often can anticipate the habitat use of their main predator and may use protective associates (i.e. typically an apex predator) as shields against predation. Although never tested, such mechanisms should also evolve in systems in which sexual conflict affects offspring survival. Here, we assessed the relationship between offspring survival and habitat selection, as well as the use of protective associates, in a system in which sexually selected infanticide (SSI), rather than interspecific predation, affects offspring survival. We used the Scandinavian brown bear ( Ursus arctos ) population with SSI in a human-dominated landscape as our model system. Bears, especially adult males, generally avoid humans in our study system. We used resource selection functions to contrast habitat selection of GPS-collared mothers that were successful (i.e. surviving litters, n = 19) and unsuccessful (i.e. complete litter loss, n = 11) in keeping their young during the mating season (2005–2012). Habitat selection was indeed a predictor of litter survival. Successful mothers were more likely to use humans as protective associates, whereas unsuccessful mothers avoided humans. Our results suggest that principles of predator–prey and fear ecology theory (e.g. non-consumptive and cascading effects) can also be applied to the context of sexual conflict.

scholarly journals Intraovarian Immunolocalization of Steroidogenic Enzymes in a Hokkaido Brown Bear, Ursus arctos yesoensis during the Mating Season.

1996 ◽  
Vol 58 (8) ◽  
pp. 787-790 ◽  
Author(s):  
Hiroshi ARAKI ◽  
Toshio TSUBOTA ◽  
Naoko MAEDA ◽  
Nobuhiro HARADA ◽  
Shiro KOMINAMI ◽  
...  
Keyword(s):  
Ursus Arctos ◽  
Brown Bear ◽  
Mating Season ◽  
Steroidogenic Enzymes

scholarly journals Activity patterns in the reintroduced Pyrenean brown bear population

2020 ◽  
Vol 65 (3) ◽  
pp. 435-444
Author(s):  
Aida Parres ◽  
Santiago Palazón ◽  
Ivan Afonso ◽  
Pierre-Yves Quenette ◽  
Antoni Batet ◽  
...  
Keyword(s):  
Ursus Arctos ◽  
Activity Patterns ◽  
Age Groups ◽  
Brown Bear ◽  
Adult Males ◽  
Mating Season ◽  
Intraspecific Interactions ◽  
Management Interventions ◽  
Different Types ◽  
Time Selection

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.

scholarly journals Emergence of a novel interaction between brown bear and cicada due to anthropogenic habitat modification

2020 ◽  
Author(s):  
Kanji Tomita ◽  
Tsutom Hiura
Keyword(s):  
Species Interactions ◽  
Ursus Arctos ◽  
Novel Species ◽  
Brown Bear ◽  
Habitat Modification ◽  
Natural Forests ◽  
Predator Prey ◽  
Anthropogenic Habitat ◽  
Typical Type ◽  
Prey Interaction

AbstractNovel species interactions have generally emerged in ecosystems that are highly modified by human activities. Anthropogenic habitat modification, such as afforestation, is one possible driver of novel species interactions; however, empirical evidence remains scarce. In this study, we show that a novel predator-prey interaction between the brown bear (Ursus arctos) and nymphs of a cicada species (Lyristes bihamatus) is generated by anthropogenic habitat modification. We evaluated the frequency of brown bear predation on cicada nymphs and the density of cicada nymphs between natural forests and plantations, which are a typical type of human-modified habitat. We found that brown bear predation on cicada nymphs occurred only in the plantations. The density of cicada nymphs in the plantations was significantly higher than in the natural forest. Our results indicate that the plantation leads to the emergence of the bear-cicada interaction due to increasing the density of cicada nymphs. The study draws attention to the overlooked effects of anthropogenic habitat modification on species interactions.

scholarly journals Spatial ecology of conflicts: unravelling patterns of wildlife damage at multiple scales

2021 ◽  
Vol 288 (1958) ◽  
pp. 20211394
Author(s):  
Carlos Bautista ◽  
Eloy Revilla ◽  
Teresa Berezowska-Cnota ◽  
Néstor Fernández ◽  
Javier Naves ◽  
...  
Keyword(s):  
Resource Selection ◽  
Spatial Ecology ◽  
Ursus Arctos ◽  
Multiple Scales ◽  
Brown Bear ◽  
Additive Models ◽  
Natural Habitats ◽  
Spatial Risk ◽  
Eastern Carpathians ◽  
Wildlife Damage

Human encroachment into natural habitats is typically followed by conflicts derived from wildlife damage to agriculture and livestock. Spatial risk modelling is a useful tool to gain the understanding of wildlife damage and mitigate conflicts. Although resource selection is a hierarchical process operating at multiple scales, risk models usually fail to address more than one scale, which can result in the misidentification of the underlying processes. Here, we addressed the multi-scale nature of wildlife damage occurrence by considering ecological and management correlates interacting from household to landscape scales. We studied brown bear ( Ursus arctos ) damage to apiaries in the North-eastern Carpathians as our model system. Using generalized additive models, we found that brown bear tendency to avoid humans and the habitat preferences of bears and beekeepers determine the risk of bear damage at multiple scales. Damage risk at fine scales increased when the broad landscape context also favoured damage. Furthermore, integrated-scale risk maps resulted in more accurate predictions than single-scale models. Our results suggest that principles of resource selection by animals can be used to understand the occurrence of damage and help mitigate conflicts in a proactive and preventive manner.

scholarly journals Habitat Selection by Brown Bears with Varying Levels of Predation Rates on Ungulate Neonates

Diversity ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 678
Author(s):  
Kate Twynham ◽  
Andrés Ordiz ◽  
Ole-Gunnar Støen ◽  
Geir-Rune Rauset ◽  
Jonas Kindberg ◽  
...  
Keyword(s):  
Habitat Selection ◽  
Resource Selection ◽  
Rangifer Tarandus ◽  
Ursus Arctos ◽  
Brown Bear ◽  
Northern Eurasia ◽  
Home Ranges ◽  
Brown Bears ◽  
Predatory Behaviour ◽  
Resource Pulses

In northern Eurasia, large carnivores overlap with semi-domestic reindeer (Rangifer tarandus) and moose (Alces alces). In Scandinavia, previous studies have quantified brown bear (Ursus arctos) spring predation on neonates of reindeer (mostly in May) and moose (mostly in June). We explored if habitat selection by brown bears changed following resource pulses and whether these changes are more pronounced on those individuals characterised by higher predatory behaviour. Fifteen brown bears in northern Sweden (2010–2012) were fitted with GPS proximity collars, and 2585 female reindeers were collared with UHF transmitters. Clusters of bear positions were visited to investigate moose and reindeer predation. Bear kill rates and home ranges were calculated to examine bear movements and predatory behaviour. Bear habitat selection was modelled using resource selection functions over four periods (pre-calving, reindeer calving, moose calving, and post-calving). Coefficients of selection for areas closer to different land cover classes across periods were compared, examining the interactions between different degrees of predatory behaviour (i.e., high and low). Bear habitat selection differed throughout the periods and between low and high predatory bears. Differences among individuals’ predatory behaviour are reflected in the selection of habitat types, providing empirical evidence that different levels of specialization in foraging behaviour helps to explain individual variation in bear habitat selection.

Brown Bear (Ursus arctos) Habitat Use and Food Resources on Elmendorf Air Force Base, Alaska

2007 ◽  
Author(s):  
Sean D. Farley ◽  
Herman Griese ◽  
Rick Sinnott ◽  
Jessica Coltrane ◽  
Chris Garner ◽  
...  
Keyword(s):  
Habitat Use ◽  
Air Force ◽  
Ursus Arctos ◽  
Brown Bear ◽  
Food Resources ◽  
Air Force Base

scholarly journals Using Landscape Change Analysis and Stakeholder Perspective to Identify Driving Forces of Human–Wildlife Interactions

Land ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 146
Author(s):  
Mihai Mustățea ◽  
Ileana Pătru-Stupariu
Keyword(s):  
Landscape Change ◽  
Ursus Arctos ◽  
Driving Forces ◽  
Brown Bear ◽  
Mountain Range ◽  
Change Analysis ◽  
Local Stakeholders ◽  
Stakeholder Perspective ◽  
Forested Ecosystems ◽  
Forest Habitats

Human–wildlife interactions (HWI) were frequent in the post-socialist period in the mountain range of Central European countries where forest habitats suffered transitions into built-up areas. Such is the case of the Upper Prahova Valley from Romania. In our study, we hypothesized that the increasing number of HWI after 1990 could be a potential consequence of woodland loss. The goal of our study was to analyse the effects of landscape changes on HWI. The study consists of the next steps: (i) applying 450 questionnaires to local stakeholders (both citizens and tourists) in order to collect data regarding HWI temporal occurrences and potential triggering factors; (ii) investigating the relation between the two variables through the Canonical Correspondence Analysis (CCA); (iii) modelling the landscape spatial changes between 1990 and 2018 for identifying areas with forest loss; (iv) overlapping the distribution of both the households affected by HWI and areas with loss of forested ecosystems. The local stakeholders indicate that the problematic species are the brown bear (Ursus arctos), the wild boar (Sus scrofa), the red fox (Vulpes vulpes) and the grey wolf (Canis lupus). The number of animal–human interactions recorded an upward trend between 1990 and 2018, and the most significant driving factors were the regulation of hunting practices, the loss of habitats, and artificial feeding. The landscape change analysis reveals that between 1990 and 2018, the forest habitats were replaced by built-up areas primarily on the outskirts of settlements, these areas coinciding with frequent HWI. The results are valid for both forest ecosystems conservation in the region, wildlife management, and human infrastructures durable spatial planning.

Plasma ochratoxin A in the European brown bear ( Ursus arctos L.) from Croatia

2017 ◽  
Vol 280 ◽  
pp. S198
Author(s):  
Dubravka Rašić ◽  
Maja Lazarus ◽  
Đuro Huber ◽  
Slaven Reljić ◽  
Maja Peraica
Keyword(s):  
Ochratoxin A ◽  
Ursus Arctos ◽  
Brown Bear
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