Factors influencing the success of capturing European brown bears with foot snares

Mammalia ◽  
2022 ◽  
Vol 0 (0) ◽  
Author(s):  
Joana Pereira ◽  
Luís Miguel Rosalino ◽  
Slaven Reljić ◽  
Natarsha Babic ◽  
Djuro Huber
Keyword(s):  
Brown Bear ◽  
Key Factors ◽  
Animal Suffering ◽  
Free Living ◽  
Trap Design ◽  
Data Set ◽  
Brown Bears ◽  
Capture Process ◽  
Feeding Sites ◽  
Free Ranging

Abstract Management of free-ranging wildlife may include the capture of animals, with the implication that the capture process is optimized, both logistically and economically and in a way that avoids animal suffering, injury or accidental mortality. Studies targeting the optimization of trapping techniques are scarce, especially when focusing on large European mammals. Therefore, to fill this knowledge gap, we aimed to evaluate key factors that help determine brown bear capture success. This was done by analysing a complete data set from 23 years of capturing free-living Eurasian brown bears in Croatia by using Aldrich-type foot snares. Results showed significantly higher capture efficiency when traps were located at permanent feeding sites when compared to temporary feeding sites. Also, the use of a trail trap design was significantly more efficient in capturing bears than using a cubby set. Finally, results showed that trapping was more efficient when we bait the traps more frequently and when we implemented longer trap-sessions, with at least 14 days.

Decrease in the red cell cofactor 2,3-diphosphoglycerate increases hemoglobin oxygen affinity in the hibernating brown bear Ursus arctos

2013 ◽  
Vol 304 (1) ◽  
pp. R43-R49 ◽  
Author(s):  
Inge G. Revsbech ◽  
Hans Malte ◽  
Ole Fröbert ◽  
Alina Evans ◽  
Stéphane Blanc ◽  
...  
Keyword(s):  
Ursus Arctos ◽  
Oxygen Affinity ◽  
Brown Bear ◽  
Temperature Sensitive ◽  
Red Cell ◽  
Brown Bears ◽  
Hemoglobin Oxygen Affinity ◽  
Free Ranging ◽  
Winter Hibernation

During winter hibernation, brown bears ( Ursus arctos) reduce basal O2 consumption rate to ∼25% compared with the active state, while body temperature decreases moderately (to ∼30°C), suggesting a temperature-independent component in their metabolic depression. To establish whether changes in O2 consumption during hibernation correlate with changes in blood O2 affinity, we took blood samples from the same six individuals of hibernating and nonhibernating free-ranging brown bears during winter and summer, respectively. A single hemoglobin (Hb) component was detected in all samples, indicating no switch in Hb synthesis. O2 binding curves measured on red blood cell lysates at 30°C and 37°C showed a less temperature-sensitive O2 affinity than in other vertebrates. Furthermore, hemolysates from hibernating bears consistently showed lower cooperativity and higher O2 affinity than their summer counterparts, regardless of the temperature. We found that this increase in O2 affinity was associated with a significant decrease in the red cell Hb-cofactor 2,3-diphosphoglycerate (DPG) during hibernation to approximately half of the summer value. Experiments performed on purified Hb, to which DPG had been added to match summer and winter levels, confirmed that the low DPG content was the cause of the left shift in the Hb-O2 equilibrium curve during hibernation. Levels of plasma lactate indicated that glycolysis is not upregulated during hibernation and that metabolism is essentially aerobic. Calculations show that the increase in Hb-O2 affinity and decrease in cooperativity resulting from decreased red cell DPG may be crucial in maintaining a fairly constant tissue oxygen tension during hibernation in vivo.

scholarly journals Trichinella spp. in Wild Boars (Sus scrofa), Brown Bears (Ursus arctos), Eurasian Lynxes (Lynx lynx) and Badgers (Meles meles) in Estonia, 2007–2014

Animals ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 183
Author(s):  
Age Kärssin ◽  
Liidia Häkkinen ◽  
Annika Vilem ◽  
Pikka Jokelainen ◽  
Brian Lassen
Keyword(s):  
Sus Scrofa ◽  
Ursus Arctos ◽  
Brown Bear ◽  
Meles Meles ◽  
Lynx Lynx ◽  
Brown Bears ◽  
Wild Boars ◽  
Infection Pressure ◽  
High Infection ◽  
Free Ranging

In this study, we summarize Trichinella findings from four wild, free-ranging host species from Estonia during 2007–2014. Trichinella spp. larvae were detected in 281 (0.9%, 95% confidence interval (CI) 0.8–1.0) of 30,566 wild boars (Sus scrofa), 63 (14.7%, 95% CI 11.6–18.3) of 429 brown bears (Ursus arctos), 59 (65.56%, 95% CI 55.3–74.8) of 90 Eurasian lynxes (Lynx lynx), and three (60.0%, 95% CI 18.2–92.7) of five badgers (Meles meles). All four European Trichinella species were detected: T. britovi in 0.7% of the wild boars, 7.2% of the brown bears, 45.6% of the lynxes, and 40.0% of the badgers; T. nativa in 0.1% of the wild boars, 5.8% of the brown bears, and 20.0% of the lynxes; T. pseudospiralis in 0.02% the wild boars; and T. spiralis in 0.03% of the wild boars and 4.4% of the lynxes. The results include the first description from Estonia of T. britovi in brown bear and badgers, T. pseudospiralis in wild boars, and T. spiralis in wild boars and lynxes. The results indicate high infection pressure in the sylvatic cycles across the years—illustrating continuous risk of spillover to domestic cycles and of transmission to humans.

scholarly journals Effects of different doses of medetomidine and tiletamine–zolazepam on the duration of induction and immobilization in free-ranging yearling brown bears (Ursus arctos)

2012 ◽  
Vol 90 (6) ◽  
pp. 753-757 ◽  
Author(s):  
Johanna Painer ◽  
Andreas Zedrosser ◽  
Jon M. Arnemo ◽  
Åsa Fahlman ◽  
Sven Brunberg ◽  
...  
Keyword(s):  
Ursus Arctos ◽  
Brown Bear ◽  
Lower Probability ◽  
Depth Of Anaesthesia ◽  
Brown Bears ◽  
Prolonged Duration ◽  
Induction Times ◽  
The Individual ◽  
Free Ranging ◽  
Different Doses

We compared anesthetic protocols with different doses of tiletamine–zolazepam (TZ) combined with medetomidine (M) for 288 yearling brown bear ( Ursus arctos L., 1758) immobilizations with the objective of finding a combination of doses that would provide fast induction with a duration of anesthesia long enough to minimize the need for administering additional drug. The duration of induction time and immobilization was dose-dependent. Increasing the M dose resulted in significantly shorter induction times and a lower probability of giving supplemental drugs. Increasing the TZ dose prolonged duration of anesthesia. For yearling brown bears in Scandinavia, captured shortly after den emergence in April and May, we recommend total dart doses of 1.0–1.66 mg M/dart, plus 62.5–125 mg TZ/dart, depending on the individual requirements for the length and depth of anaesthesia.

Ants: A food source sought by Slovenian brown bears (Ursus arctos)?

2003 ◽  
Vol 81 (12) ◽  
pp. 1996-2005 ◽  
Author(s):  
C Große ◽  
P Kaczensky ◽  
F Knauer
Keyword(s):  
Habitat Suitability ◽  
Food Source ◽  
Ursus Arctos ◽  
Brown Bear ◽  
Dry Mass ◽  
Artificial Feeding ◽  
Frequency Of Occurrence ◽  
Brown Bears ◽  
Ant Colonies ◽  
Feeding Sites

In the heavily managed boreal forest of Scandinavia, ants, especially large colonies of red forest ants (Formica spp.), are abundant and brown bears (Ursus arctos) intensively feed on them. In contrast, the beech (Fagus sylvatica) forests of Slovenia provide only suboptimal habitat for ants and large ant colonies are virtually absent. To quantify how much ant use by brown bears is a matter of availability or preference, we quantified ant availability, species composition, and ant use. The estimated biomass of ants available to brown bears was very low in Slovenia compared with those in Sweden, averaging 135 vs. 9600 g/ha, respectively. Nevertheless, the frequency of occurrence of ants in Slovenian brown bear scats was high, averaging 85% and accounting for 25% of the ingested dry mass during the summer, which was nearly as much as their frequency of occurrence in Swedish brown bear scats during the summer. Although brown bears in Slovenia had year-round access to artificial feeding sites and the availability of ants is only about 1% of the biomass found in Sweden, they consumed about 50% of the quantity of ants compared with the brown bears in Sweden. Our results show that ants are an important and sought-after food source for brown bears in Slovenia, and the occurrence of ants should be considered in habitat-suitability models.

scholarly journals Identifying priority core habitats and corridors for effective conservation of brown bears in Iran

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
A. Mohammadi ◽  
K. Almasieh ◽  
D. Nayeri ◽  
F. Ataei ◽  
A. Khani ◽  
...  
Keyword(s):  
Protected Areas ◽  
Brown Bear ◽  
Population Connectivity ◽  
Habitat Associations ◽  
Area Network ◽  
Zagros Mountains ◽  
Range Limit ◽  
Brown Bears ◽  
Core Areas ◽  
Effective Conservation

AbstractIran lies at the southernmost range limit of brown bears globally. Therefore, understanding the habitat associations and patterns of population connectivity for brown bears in Iran is relevant for the species’ conservation. We applied species distribution modeling to predict habitat suitability and connectivity modeling to identify population core areas and corridors. Our results showed that forest density, topographical roughness, NDVI and human footprint were the most influential variables in predicting brown bear distribution. The most crucial core areas and corridor networks for brown bear are concentrated in the Alborz and Zagros Mountains. These two core areas were predicted to be fragmented into a total of fifteen isolated patches if dispersal of brown bear across the landscape is limited to 50,000 cost units, and aggregates into two isolated habitat patches if the species is capable of dispersing 400,000 cost units. We found low overlap between corridors, and core habitats with protected areas, suggesting that the existing protected area network may not be adequate for the conservation of brown bear in Iran. Our results suggest that effective conservation of brown bears in Iran requires protection of both core habitats and the corridors between them, especially outside Iran’s network of protected areas.

scholarly journals Mixing Uncertainties in Low-Metallicity AGB Stars: The Impact on Stellar Structure and Nucleosynthesis

Universe ◽  
2021 ◽  
Vol 7 (2) ◽  
pp. 25
Author(s):  
Umberto Battino ◽  
Claudia Lederer-Woods ◽  
Borbála Cseh ◽  
Pavel Denissenkov ◽  
Falk Herwig
Keyword(s):  
Stellar Structure ◽  
Process Efficiency ◽  
Agb Stars ◽  
Mixing Processes ◽  
Data Set ◽  
Convective Envelope ◽  
Capture Process ◽  
Low Metallicity ◽  
Low Mass ◽  
The Impact

The slow neutron-capture process (s-process) efficiency in low-mass AGB stars (1.5 < M/M⊙ < 3) critically depends on how mixing processes in stellar interiors are handled, which is still affected by considerable uncertainties. In this work, we compute the evolution and nucleosynthesis of low-mass AGB stars at low metallicities using the MESA stellar evolution code. The combined data set includes models with initial masses Mini/M⊙=2 and 3 for initial metallicities Z=0.001 and 0.002. The nucleosynthesis was calculated for all relevant isotopes by post-processing with the NuGrid mppnp code. Using these models, we show the impact of the uncertainties affecting the main mixing processes on heavy element nucleosynthesis, such as convection and mixing at convective boundaries. We finally compare our theoretical predictions with observed surface abundances on low-metallicity stars. We find that mixing at the interface between the He-intershell and the CO-core has a critical impact on the s-process at low metallicities, and its importance is comparable to convective boundary mixing processes under the convective envelope, which determine the formation and size of the 13C-pocket. Additionally, our results indicate that models with very low to no mixing below the He-intershell during thermal pulses, and with a 13C-pocket size of at least ∼3 × 10−4 M⊙, are strongly favored in reproducing observations. Online access to complete yield data tables is also provided.

Sexing free-ranging brown bears Ursus arctos using hairs found in the field

1993 ◽  
Vol 2 (6) ◽  
pp. 399-403 ◽  
Author(s):  
P. TABERLET ◽  
H. MATTOCK ◽  
C. DUBOIS-PAGANON ◽  
J. BOUVET
Keyword(s):  
Ursus Arctos ◽  
Brown Bears ◽  
Free Ranging

scholarly journals The smell of success: Reproductive success related to rub behavior in brown bears

PLoS ONE ◽  
2021 ◽  
Vol 16 (3) ◽  
pp. e0247964
Author(s):  
Andrea T. Morehouse ◽  
Anne E. Loosen ◽  
Tabitha A. Graves ◽  
Mark S. Boyce
Keyword(s):  
Reproductive Success ◽  
Ursus Arctos ◽  
Scent Marking ◽  
Brown Bear ◽  
Parentage Analysis ◽  
Fitness Component ◽  
Brown Bears ◽  
Male And Female ◽  
Rubbing Behavior ◽  
Insight Into

Several species of bears are known to rub deliberately against trees and other objects, but little is known about why bears rub. Patterns in rubbing behavior of male and female brown bears (Ursus arctos) suggest that scent marking via rubbing functions to communicate among potential mates or competitors. Using DNA from bear hairs collected from rub objects in southwestern Alberta from 2011–2014 and existing DNA datasets from Montana and southeastern British Columbia, we determined sex and individual identity of each bear detected. Using these data, we completed a parentage analysis. From the parentage analysis and detection data, we determined the number of offspring, mates, unique rub objects where an individual was detected, and sampling occasions during which an individual was detected for each brown bear identified through our sampling methods. Using a Poisson regression, we found a positive relationship between bear rubbing behavior and reproductive success; both male and female bears with a greater number of mates and a greater number of offspring were detected at more rub objects and during more occasions. Our results suggest a fitness component to bear rubbing, indicate that rubbing is adaptive, and provide insight into a poorly understood behaviour.

scholarly journals Molecular survey of Besnoitia spp. (Apicomplexa) in faeces from European wild mesocarnivores in Spain. Short running title: Molecular survey of Besnoitia spp in faeces from wild carnivores.

2021 ◽  
Author(s):  
David González-Barrio ◽  
Pamela C. Köster ◽  
Miguel Habela ◽  
Manuel Martín-Pérez ◽  
José Fernández-García ◽  
...  
Keyword(s):  
Definitive Host ◽  
Red Foxes ◽  
Besnoitia Besnoiti ◽  
Free Living ◽  
Wild Carnivores ◽  
Molecular Survey ◽  
Faecal Samples ◽  
Bovine Besnoitiosis ◽  
Western Spain ◽  
Free Ranging

Numerous studies have unsuccessfully tried to unravel the definitive host of the coccidian parasite Besnoitia besnoiti. Cattle infections by B. besnoiti cause a chronic and debilitating condition called bovine besnoitiosis that has emerged in Europe during the last two decades, mainly due to limitations in its control associated to the absence of vaccines and therapeutical tools. Although the exact transmission pathway of B. besnoiti is currently unknown, it is assumed that the parasite might have an indirect life cycle with a carnivore as definitive host. Current lack of studies in wildlife might underestimate the importance of free-living species in the epidemiology of B. besnoiti. Thus, the aim of the present study is to assess the presence of Besnoitia spp. in free-ranging mesocarnivores in Spain. DNA was searched by PCR on faeces collected from wild carnivores as a first approach to determine which species could be considered as potential definitive host candidates in further research. For this purpose, a total of 352 faecal samples from 12 free-living wild carnivore species belonging to the Canidae, Felidae, Herpestidae, Mustelidae, Procyonidae, and Viverridae families were collected in seven Spanish regions. PCR testing showed that Besnoitia spp. DNA was present in four faecal samples from red foxes collected in western Spain, an area with the greatest density of extensively reared cattle and associated to high incidence of bovine besnoitiosis in the country. To date, this is the first report of a Besnoitia besnoiti-like sequence (99.57% homology) from carnivore faeces in a worldwide context. Red foxes might contribute to the epidemiology of B. besnoiti, although further studies, mostly based on bioassay, would be needed to elucidate the accuracy and extent of these interesting findings.

scholarly journals Specific shifts in the endocannabinoid system in hibernating brown bears

2020 ◽  
Author(s):  
Christian Boyer ◽  
Laura Cussonneau ◽  
Charlotte Brun ◽  
Christiane Deval ◽  
Jean-Paul Pais de Barros ◽  
...  
Keyword(s):  
Fatty Acid ◽  
Ursus Arctos ◽  
Mild Hypothermia ◽  
Endocannabinoid System ◽  
Fold Increase ◽  
Physiological Adaptation ◽  
Acid Oxidation ◽  
Brown Bears ◽  
Peripheral Tissues ◽  
Free Ranging

Abstract In small hibernators, global downregulation of the endocannabinoid system (ECS), which is involved in modulating neuronal signaling, feeding behavior, energy metabolism, and circannual rhythms, has been reported to possibly drive physiological adaptation to the hibernating state. We hypothesized that specific changes should occur in hibernating brown bears ( Ursus arctos ) due to specific features, including hibernation during half the year at only mild hypothermia while remaining physically inactive without drinking or eating, and the absence of arousal episodes although bears remain sensitive to external disturbances. We explored circulating lipids and the ECS in plasma and metabolically active tissues (muscle and adipose tissue), in free-ranging subadult Scandinavian brown bears when both active and hibernating. In winter bear serum, in addition to a 2-fold increase in total fatty acid concentration, we found significant changes in relative proportions of circulating fatty acids, such as a 2-fold increase in docosahexaenoic acid and a decrease in arachidonic acid. In adipose and muscle tissues of hibernating bears, we found lower concentrations of both two major ligands for endocannabinoid receptors, 2-arachidonoylglycerol (2-AG) and anandamide (AEA). Gene expression was reduced for enzymes that synthesize endocannabinoid compounds, whereas an increase was observed for catabolic enzymes. Reduction in ECS tone may promote mobilization of fat stores and favor carbohydrate metabolism in skeletal muscle of hibernating bears. Additionally, high circulating of the endocannabinoid-like compound N-oleoylethanolamide (OEA) in winter could favor lipolysis and fatty acid oxidation in peripheral tissues. We also speculated on a role of OEA in the maintenance of torpor (reduction in locomotion), while promoting the capacity of bears to sense stimuli from the environment.

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