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Henrik Brøseth

Bio: Henrik Brøseth is an academic researcher. The author has contributed to research in topics: Population & Eurasian lynx. The author has an hindex of 27, co-authored 90 publications receiving 3213 citations.


Papers
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Journal ArticleDOI
19 Dec 2014-Science
TL;DR: It is shown that roughly one-third of mainland Europe hosts at least one large carnivore species, with stable or increasing abundance in most cases in 21st-century records, and coexistence alongside humans has become possible, argue the authors.
Abstract: The conservation of large carnivores is a formidable challenge for biodiversity conservation. Using a data set on the past and current status of brown bears (Ursus arctos), Eurasian lynx (Lynx lynx), gray wolves (Canis lupus), and wolverines (Gulo gulo) in European countries, we show that roughly one-third of mainland Europe hosts at least one large carnivore species, with stable or increasing abundance in most cases in 21st-century records. The reasons for this overall conservation success include protective legislation, supportive public opinion, and a variety of practices making coexistence between large carnivores and people possible. The European situation reveals that large carnivores and people can share the same landscape.

1,290 citations

01 Jan 2012
TL;DR: In this article, an expert based update of the conservation status of all populations identified by the Large Carnivore Initiative for Europe (LCIE), available in the document “Guidelines for Population Level Management Plans for Large carnivores” (Linnell et al. 2008) and/or in the various Species Online Information Systems (http://www.lcie.kora.ch/sp‐ois/ ; also see Appendix 1).
Abstract: Large carnivores (bears Ursus arctos, wolves Canis lupus, lynx Lynx lynx and wolverines Gulo gulo) are among the most challenging group of species to maintain as large and continuous populations or to reintegrate back into the European landscape. Political, socioeconomic and society changes challenge past management approaches in some of the large populations. At the same time local improvements in habitat quality, the return of their prey species, public support and favourable legislation allow for the recovery of some small populations. Several of Europe’s large carnivore populations are large and robust, others are expanding, some small populations remain critically endangered and a few are declining. [ ] Large carnivores need very large areas and their conservation needs to be planned on very wide spatial scales that will often span many intra‐ and inter‐ national borders. Within these large scales conservation and management actions need to be coordinated. To facilitate coordination, a common understanding of the present day conservation status of large carnivores at national and population level is an important basis. [ ] The aim of this summary report is to provide an expert based update of the conservation status of all populations identified by the Large Carnivore Initiative for Europe (LCIE), available in the document “Guidelines for Population Level Management Plans for Large Carnivores” (Linnell et al. 2008) and/or in the various Species Online Information Systems (http://www.kora.ch/sp‐ois/ ; also see Appendix 1). [ ] However, methods used to monitor large carnivores vary and a direct comparison over time or among populations will never be possible at a continental scale. It is more realistic to have an insight into the general order of magnitude of the population, its trend and permanent range as the “currencies” for comparisons and assessments (see point 2). This summary also does not aim to replace the habitat directive reporting, but rather complement it. Discrepancies will likely occur due to different time periods covered and different agreements reached on common reporting criteria on a national level which has to deal with many more species. Furthermore, for several countries the most recent data or distribution map were not always available, yet. [ ] Changes in monitoring methods likely result in changing population estimates, even in stable populations. Improved and more costly methods may suddenly discover that previous estimates were too high, or may detect more individuals than previously assumed. Examples of both occur. Being aware of the change in methodology the expert assessment may still be “stable” for the population even if numbers listed in tables have changed. On the other hand, large scale “official” (government) estimates may be based on questionable or non‐transparent extrapolations that run contrary to data from reference areas within the country or similar regions from other countries. If the discrepancy is apparent, expert assessment needs to question official numbers. [ ] This summary does not aim at reviewing monitoring techniques. Examples of parameters and principles for monitoring large carnivores and some “good practice” examples have been previously compiled by the LCIE (http://www.lcie.org/Docs/LCIE%20IUCN/LCIE_PSS_m onitoring.pdf). Furthermore, references at the end of many country reports do provide ample examples of well documented and state of the art monitoring of large carnivores in Europe under a wide variety of different contexts.

183 citations

Journal ArticleDOI
TL;DR: Seasonal quotas based on proportional harvest were effective and should be set at ≤ 15% of August populations for regional management plans and the superadditive hypothesis was supported because birds in the 30% harvest treatment had higher natural mortality during winter after the hunting season.
Abstract: Summary 1. The effects of harvest on the annual and seasonal survival of willow ptarmigan Lagopus lagopus L. were tested in a large-scale harvest experiment. Management units were randomly assigned to one of three experimental treatments: 0%, 15% or 30% harvest. Seasonal quotas were based on the experimental treatment and estimates of bird density before the hunting season. Survival rates and hazard functions for radio-marked ptarmigan were then estimated under the competing risks of harvest and natural mortality. 2. The partially compensatory mortality hypothesis was supported: annual survival of ptarmigan was 0AE 54 ±0 AE08 SE under 0% harvest, 0AE47 ± 0AE06 under 15% harvest, and was reduced to 0AE 30 ±0 AE05 under 30% harvest. Harvest mortality increased linearly from 0AE08 ± 0AE05, 0AE27 ± 0AE05 and 0AE42 ± 0AE06 from 0% to 30% harvest, whereas natural mortality was 0AE38 ± 0AE08, 0AE 25 ±0 AE05 and 0AE 28 ±0 AE06 under the same treatments. 3. Realized risk of harvest mortality was 0AE08-0AE12 points higher than our set harvest treatments of 0–30% because birds were exposed to risk if they moved out of protected areas. The superadditive hypothesis was supported because birds in the 30% harvest treatment had higher natural mortality during winter after the hunting season. 4. Natural mortality was mainly because of raptor predation, with two seasonal peaks in fall and spring. Natural and harvest mortality coincided during early autumn with little potential for compensation during winter months. Peak risk of harvest mortality was 5· higher than natural mortality. Low natural mortality during winter suggests that most late season harvest would be additive mortality. 5. Environmental correlates of natural mortality of ptarmigan included seasonal changes in snow cover, onset of juvenile dispersal, and periods of territorial activity. Natural mortality of ptarmigan was highest during autumn movements and nesting by gyrfalcons Falco rusticolus L. Mortality was low when gyrfalcons had departed for coastal wintering sites, and during summer when ptarmigan were attending nests and broods. 6. Our experimental results have important implications for harvest management of upland gamebirds. Seasonal quotas based on proportional harvest were effective and should be set at £15% of August populations for regional management plans. Under threshold harvest of a reproductive surplus, 15% harvest would be sustainable at productivity rates ‡2AE5 young per pair. Impacts of winter harvest could be minimized by closing the hunting season in early November or by reducing late season quotas.

153 citations

Journal ArticleDOI
TL;DR: Bayesian analysis and subsequent assessment of individual relationships suggest that immigrants from northern Scandinavia have contributed and still contribute to the southern Norwegian gene pool, counteracting genetic erosion and reducing the risk of inbreeding depression.
Abstract: The southern Norwegian wolverine (Gulo gulo) population was considered functionally extinct in the 1960s but has partly recovered in recent years. Proper management of this population is highly dependent on reliable estimates of critical population parameters such as population size, sex ratio, immigration rate, and reproductive contribution from immigrants. We report on a large-scale population monitoring project assessing these parameters through genetic tagging of individuals, with feces as the source of DNA. Sixty-eight different individuals were detected among 147 successfully genotyped samples collected in 2000 and 2001. Sixty of these individuals were represented in the 2001 sample, which may be considered a minimum estimate of the population size. Almost 50% of these animals were sampled only once, however, indicating that the true population size may be markedly higher. Accordingly, a capture-recapture estimate based on the observed resampling rates suggested a population size of 89 wolverines (95% confidence interval (CI) = 74-104), which is approximately 35% higher than an estimate of 64 obtained from the number of active natal dens (95% CI = 46-95; p = 0.08). Indirect estimates of dispersal distances inferred from mother-offspring relationships sug- gested that wolverine males have the ability to disperse up to 500 km, a distance exceeding anything previously reported in the literature. Dispersal distances of more than 100 km were detected for females. Bayesian clus- tering analysis and subsequent assessment of individual relationships suggest that immigrants from northern Scandinavia have contributed and still contribute to the southern Norwegian gene pool, counteracting genetic erosion and reducing the risk of inbreeding depression. Additional sampling efforts will be undertaken during the coming years to allow for observations of population trends, immigration rate, and reproductive variance among individuals. Such data will provide an important basis for the design of an appropriate conservation plan for this small and vulnerable population.

134 citations

Journal ArticleDOI
01 Jun 2005-Ecology
TL;DR: In this paper, the authors estimate the spatial scaling of the component that is due to environmental stochasticity in the population dynamics of roe deer (Capreolus capreolaus) in Norway.
Abstract: Theoretical analyses have shown that the spatial scaling of environmental autocorrelation, strength of density regulation, and the dispersal of individuals determine the scaling of synchrony in population fluctuations. By modeling the separate effects of density regulation, environmental stochasticity, and demographic stochasticity, we estimate the spatial scaling of the component that is due to environmental stochasticity in the population dynamics of roe deer (Capreolus capreolus) in Norway. The estimated spatial scaling of the environmental noise was ∼200 km. An examination of how different weather variables influenced the scaling indicated that snow depth was the major weather variable affecting the scaling of synchrony in population fluctuations, and was negatively related to population growth rates in 97.4% of the 151 populations included in the study. A large-scale climatic phenomenon, the North Atlantic Oscillation, was positively related to population growth rates in 94.7% of the populations but ...

116 citations


Cited by
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Journal ArticleDOI
19 Dec 2014-Science
TL;DR: It is shown that roughly one-third of mainland Europe hosts at least one large carnivore species, with stable or increasing abundance in most cases in 21st-century records, and coexistence alongside humans has become possible, argue the authors.
Abstract: The conservation of large carnivores is a formidable challenge for biodiversity conservation. Using a data set on the past and current status of brown bears (Ursus arctos), Eurasian lynx (Lynx lynx), gray wolves (Canis lupus), and wolverines (Gulo gulo) in European countries, we show that roughly one-third of mainland Europe hosts at least one large carnivore species, with stable or increasing abundance in most cases in 21st-century records. The reasons for this overall conservation success include protective legislation, supportive public opinion, and a variety of practices making coexistence between large carnivores and people possible. The European situation reveals that large carnivores and people can share the same landscape.

1,290 citations

Journal ArticleDOI
TL;DR: It is illustrated how DNA and population genetic data can provide valuable information, often unattainable via other approaches, for monitoring species of management, conservation and ecological interest.
Abstract: In response to ever-increasing anthropogenic changes to natural ecosystems, regional, national and international organizations have established guidelines for monitoring biological diversity. Most monitoring programs, however, do not take full advantage of the potential afforded by molecular genetic markers, which can provide information relevant to both ecological and evolutionary time frames, while costing less and being more sensitive and reliable than traditional monitoring approaches. As several molecular and computational approaches are relatively new, many technical and theoretical issues remain to be resolved. Here, we illustrate how DNA and population genetic data can provide valuable information, often unattainable via other approaches, for monitoring species of management, conservation and ecological interest.

1,072 citations

Journal ArticleDOI
TL;DR: The authors argue that the evidence for population-level effects of roads and traffic is already strong enough to merit routine consideration of mitigation of these effects in all road construction and maintenance projects.
Abstract: The authors attempted a complete review of the empirical literature on effects of roads and traffic on animal abundance and distribution. They found 79 studies, with results for 131 species and 30 species groups. Overall, the number of documented negative effects of roads on animal abundance outnumbered the number of positive effects by a factor of 5; 114 responses were negative, 22 were positive, and 56 showed no effect. Amphibians and reptiles tended to show negative effects. Birds showed mainly negative or no effects, with a few positive effects for some small birds and for vultures. Small mammals generally showed either positive effects or no effect, mid-sized mammals showed either negative effects or no effect, and large mammals showed predominantly negative effects. The authors synthesized this information, along with information on species attributes, to develop a set of predictions of the conditions that lead to negative or positive effects or no effect of roads on animal abundance. Four species types are predicted to respond negatively to roads: (i) species that are attracted to roads and are unable to avoid individual cars; (ii) species with large movement ranges, low reproductive rates, and low natural densities; and (iii and iv) small animals whose populations are not limited by road-affected predators and either (a) avoid habitat near roads due to traffic disturbance or (b) show no avoidance of roads or traffic disturbance and are unable to avoid oncoming cars. Two species types are predicted to respond positively to roads: (i) species that are attracted to roads for an important resource (e.g., food) and are able to avoid oncoming cars, and (ii) species that do not avoid traffic disturbance but do avoid roads, and whose main predators show negative population-level responses to roads. Other conditions lead to weak or non-existent effects of roads and traffic on animal abundance. The authors identify areas where further research is needed, but they also argue that the evidence for population-level effects of roads and traffic is already strong enough to merit routine consideration of mitigation of these effects in all road construction and maintenance projects.

1,038 citations

Journal ArticleDOI
TL;DR: There is potential for the restoration of apex predators to have benefits for biodiversity conservation through moderation of the impacts of mesopredators on their prey, but this requires a whole-ecosystem view to avoid unforeseen negative effects.
Abstract: There is growing recognition of the important roles played by predators in regulating ecosystems and sustaining biodiversity. Much attention has focused on the consequences of predator-regulation of herbivore populations, and associated trophic cascades. However apex predators may also control smaller 'mesopredators' through intraguild interactions. Removal of apex predators can result in changes to intraguild interactions and outbreaks of mesopredators ('mesopredator release'), leading in turn to increased predation on smaller prey. Here we provide a review and synthesis of studies of predator interactions, mesopredator release and their impacts on biodiversity. Mesopredator suppression by apex predators is widespread geographically and taxonomically. Apex predators suppress mesopredators both by killing them, or instilling fear, which motivates changes in behaviour and habitat use that limit mesopredator distribution and abundance. Changes in the abundance of apex predators may have disproportionate (up to fourfold) effects on mesopredator abundance. Outcomes of interactions between predators may however vary with resource availability, habitat complexity and the complexity of predator communities. There is potential for the restoration of apex predators to have benefits for biodiversity conservation through moderation of the impacts of mesopredators on their prey, but this requires a whole-ecosystem view to avoid unforeseen negative effects. 'Nothing has changed since I began. My eye has permitted no change. I am going to keep things like this.' From 'Hawk Roosting', by Ted Hughes.

1,021 citations

01 Jan 2006
TL;DR: In this article, the authors offer suggestions related to helping a student deal with bullying in schools, as well as creating an environment where that individual can easily return to the school community.
Abstract: This section offers suggestions related to helping a student deal with bullying in schools, as well as creating an environment where that individual can easily return to the school community. It also mentions the significance of the method 'Shared Responsibility' in dealing with the situation.

755 citations