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 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 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 habitat selection in relation to anthropogenic structures in the Bieszczady Mountains, Poland

Biologia ◽  
2014 ◽  
Vol 69 (7) ◽  
Author(s):  
Witold Frąckowiak ◽  
Jörn Theuerkauf ◽  
Bartosz Pirga ◽  
Roman Gula
Keyword(s):  
Habitat Selection ◽  
Human Factors ◽  
Ursus Arctos ◽  
Brown Bear ◽  
Human Settlements ◽  
Brown Bears ◽  
Anthropogenic Structures ◽  
Selection Of

AbstractIn Europe, brown bear Ursus arctos habitats frequently overlap with human settlements and infrastructure. We tested whether anthropogenic structures played an important role in habitat selection by brown bears in the Bieszczady Mountains, Poland. We analysed 668 signs of brown bear presence recorded during 6 counts along 246 km of transects (total 1,476 km) in spring, summer and autumn of 1993 and 1994. Habitat selection of bears was more related to habitat and altitude than to human factors. Avoidance of roads, settlements and forest clearings influenced habitat selection by brown bears in spring but less in summer and autumn.

Wildlife habitat selection on landscapes with industrial disturbance

2016 ◽  
Vol 43 (4) ◽  
pp. 327-336 ◽  
Author(s):  
BOGDAN CRISTESCU ◽  
GORDON B. STENHOUSE ◽  
MARC SYMBALUK ◽  
SCOTT E. NIELSEN ◽  
MARK S. BOYCE
Keyword(s):  
Habitat Selection ◽  
Resource Selection ◽  
Ursus Arctos ◽  
Regional Scale ◽  
Surface Mining ◽  
Individual Variability ◽  
Wildlife Habitat ◽  
Public Access ◽  
Site Specific ◽  
Animal Populations

SUMMARYTechnological advancements in remote sensing and telemetry provide opportunities for assessing the effects of expanding extractive industries on animal populations. Here, we illustrate the applicability of resource selection functions (RSFs) for modelling wildlife habitat selection on industrially-disturbed landscapes. We used grizzly bears (Ursus arctos) from a threatened population in Canada and surface mining as a case study. RSF predictions based on GPS radiocollared bears (nduring mining = 7; npost mining = 9) showed that males and solitary females selected areas primarily outside mineral surface leases (MSLs) during active mining, and conversely inside MSLs after mine closure. However, females with cubs selected areas within compared to outside MSLs irrespective of mining activity. Individual variability was pronounced, although some environmental- and human-related variables were consistent across reproductive classes. For males and solitary females, regional-scale RSFs yielded comparable results to site-specific models, whereas for females with cubs, modelling the two scales produced divergent results. While mine reclamation may afford opportunities for bear persistence, managing public access will likely decrease the risk of human-caused bear mortality. RSFs are powerful tools that merit widespread use in quantitative and visual investigations of wildlife habitat selection on industrially-modified landscapes, using Geographic Information System layers that precisely characterize site-specific conditions.

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 Visual marking in mammals first proved by manipulations of brown bear tree debarking

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Vincenzo Penteriani ◽  
Enrique González-Bernardo ◽  
Alfonso Hartasánchez ◽  
Héctor Ruiz-Villar ◽  
Ana Morales-González ◽  
...  
Keyword(s):  
Ursus Arctos ◽  
Brown Bear ◽  
Visual Display ◽  
Adult Males ◽  
Mammal Species ◽  
Visual Marking ◽  
Human Ability ◽  
Intraspecific Communication ◽  
Visual Signalling ◽  
First Time

AbstractThe rather limited human ability to understand animal vision and visual signalling has frequently clouded our expectations concerning the visual abilities of other animals. But there are multiple reasons to suspect that visual signalling is more widely employed by animals than previously thought. Because visibility of visual marks depends on the background in which they are seen, species spending most of their time living in dark conditions (e.g., in forests and/or having crepuscular and nocturnal habits) may rely on bright signals to enhance visual display. Here, as a result of experimental manipulations, we present, for the first time ever, evidence supporting the use of a new channel of intraspecific communication by a mammal species, i.e., brown bear Ursus arctos adult males relying on visual marks during mating. Bear reactions to our manipulation suggest that visual signalling could represent a widely overlooked mechanism in mammal communication, which may be more broadly employed than was previously thought.

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 Brown bear communication hubs: patterns and correlates of tree rubbing and pedal marking at a long-term marking site

PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e10447
Author(s):  
Eloy Revilla ◽  
Damián Ramos Fernández ◽  
Alberto Fernández-Gil ◽  
Agnieszka Sergiel ◽  
Nuria Selva ◽  
...  
Keyword(s):  
Chemical Communication ◽  
Ursus Arctos ◽  
Brown Bear ◽  
Population Level ◽  
Adult Males ◽  
Communication Behaviors ◽  
Brown Bears ◽  
Low Frequencies ◽  
A Site

Chemical communication is important for many species of mammals. Male brown bears, Ursus arctos, mark trees with a secretion from glands located on their back. The recent discovery of pedal glands and pedal-marking at a site used for tree-rubbing led us to hypothesize that both types of marking form part of a more complex communication system. We describe the patterns of chemical communication used by different age and sex classes, including differences in the roles of these classes as information providers or receivers over four years at a long-term marking site. Using video recordings from a camera trap, we registered a total of 285 bear-visits and 419 behavioral events associated with chemical communication. Bears visited the site more frequently during the mating season, during which communication behaviors were more frequent. A typical visit by male bears consisted of sniffing the depressions where animals pedal mark, performing pedal-marking, sniffing the tree, and, finally, rubbing against the trunk of the tree. Adult males performed most pedal- and tree-marking (95% and 66% of the cases, respectively). Males pedal-marked and tree-rubbed in 81% and 48% of their visits and sniffed the pedal marks and the tree in 23% and 59% of visits, respectively. Adult females never pedal marked, and juveniles did so at very low frequencies. Females rubbed against the tree in just 9% of their visits; they sniffed the tree and the pedal marks in 51% and 21% of their visits, respectively. All sex and age classes performed pedal- and tree-sniffing. There were significant associations between behaviors indicating that different behaviors tended to occur during the same visit and were more likely if another individual had recently visited. These associations leading to repeated marking of the site can promote the establishment of long-term marking sites. Marking sites defined by trees and the trails leading to them seem to act as communication hubs that brown bears use to share and obtain important information at population level.

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 Seasonal movements of brown bears in the Middle Sikhote-Alin

2021 ◽  
pp. 78-86
Author(s):  
И.В. СЕРЁДКИН
Keyword(s):  
Ursus Arctos ◽  
Far East ◽  
Brown Bear ◽  
Young Male ◽  
Pinus Koraiensis ◽  
Sikhote Alin ◽  
Adult Males ◽  
Brown Bears ◽  
Seasonal Movements ◽  
Quercus Mongolica

Бурый медведь (Ursus arctos) на территории Дальнего Востока играет важную роль в экосистемах и имеет большое практическое значение для человека, являясь ценным объектом охоты. Важной экологической характеристикой популяции является использование пространства, включая сезонные перемещения особей. Оценивали сезонные перемещения 12 взрослых самцов, семи взрослых самок, одного молодого самца и одной молодой самки бурых медведей на Среднем Сихотэ-Алине в 1993–2011 гг. с помощью радио- и GPS-телеметрии. Для описания сезонных перемещений использовали линейную дистанцию между двумя локациями или сумму линейных смещений между последовательными локациями особей. Животных с целью мечения отлавливали лапозахватывающими ловушками Олдрича на лесных тропах и с использованием приманки; обездвиживали при помощи дистанционного инъектора с использованием анестезирующих препаратов. Значительные линейные смещения медведей наблюдали во все сезоны внеберложного периода, наибольшие из них достигали 111.5 км. Сезонные перемещения самцов были более выраженными по сравнению с таковыми самок. В постберложный период медведи совершали переходы от берлог к весенним кормовым стациям. В летний период переходы были связаны с пищевым и репродуктивным поведением. Осенью в период нажировки медведи активно перемещались в поисках нажировочных кормов – орехов сосны корейской (Pinus koraiensis) и желудей дуба монгольского (Quercus mongolica). В предберложный период медведи совершали переходы в места залегания в берлоги. Исследования, выполненные с помощью телеметрии, расширили знания экологии бурого медведя на Сихотэ-Алине, которые важны для научно обоснованного управления его популяцией. On the territory of the Far East, the brown bear (Ursus arctos) plays an important role in the ecosystems and, being valuable hunting species, has a great practical value for humans. The space use including the seasonal movements of specimens is an important ecological characteristic of population. The seasonal movements of 12 adult males, seven adult females, one young male and one young female of brown bears were evaluated in the Middle Sikhote-Alin in 1993–2011 with the use of radio- and GPS-telemetry. For description of seasonal movements, the linear distance between two locations or sum of linear displacements between the successive locations of specimens were used. With the purpose of marking, the animals were caught by the Aldrich foot snares on the forest trails and with the use of baits, immobilized using the remote injector and anesthetics. Significant linear movements of bears were observed in all seasons of the non-denning period and the largest of them reached 111.5 km. Seasonal movements of males were more pronounced than those of females. In the post-denning period, bears made passages from dens to spring feeding stations. In the summer season, the movements were related to feeding and reproductive behavior. In autumn, during the hyperphagia, the bears moved actively in search of fattening feed: Korean pine nuts (Pinus koraiensis) and Mongolian oak acorns (Quercus mongolica). In the pre-denning period, bears made passages to den places. The telemetry studies have broadened the knowledge of the brown bear ecology in the Sikhote-Alin, which is important to scientifically grounded management of its population.

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