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Janis Ozolins

Other affiliations: United States Forest Service
Bio: Janis Ozolins is an academic researcher from Forest Research Institute. The author has contributed to research in topics: Population & Eurasian lynx. The author has an hindex of 15, co-authored 19 publications receiving 1811 citations. Previous affiliations of Janis Ozolins include United States Forest Service.

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: The brown bear has proved a useful model for studying Late Quaternary mammalian phylogeography as discussed by the authors, but information is lacking from northern continental Eurasia, which constitutes a large part of the species' current distribution.
Abstract: The brown bear has proved a useful model for studying Late Quaternary mammalian phylogeography. However, information is lacking from northern continental Eurasia, which constitutes a large part of the species' current distribution. We analysed mitochondrial DNA sequences (totalling 1943 bp) from 205 bears from northeast Europe and Russia in order to characterize the maternal phylogeography of bears in this region. We also estimated the formation times of the sampled brown bear lineages and those of its extinct relative, the cave bear. Four closely related haplogroups belonging to a single mitochondrial subclade were identified in northern continental Eurasia. Several haplotypes were found throughout the whole study area, while one haplogroup was restricted to Kamchatka. The haplotype network, estimated divergence times and various statistical tests indicated that bears in northern continental Eurasia recently underwent a sudden expansion, preceded by a severe bottleneck. This brown bear population was therefore most likely founded by a small number of bears that were restricted to a single refuge area during the last glacial maximum. This pattern has been described previously for other mammal species and as such may represent one general model for the phylogeography of Eurasian mammals. Bayesian divergence time estimates are presented for different brown and cave bear clades. Moreover, our results demonstrate the extent of substitution rate variation occurring throughout the phylogenetic tree, highlighting the need for appropriate calibration when estimating divergence times.

123 citations

Journal ArticleDOI
TL;DR: The most pressing issues threatening wolf populations in Europe are discussed, important gaps in current knowledge are highlighted, solutions to overcome these limitations are suggested, and recommendations for science‐based wolf conservation and management at regional and Europe‐wide scales are provided.
Abstract: The grey wolf (Canis lupus) is an iconic large carnivore that has increasingly been recognized as an apex predator with intrinsic value and a keystone species. However, wolves have also long represented a primary source of human–carnivore conflict, which has led to long-term persecution of wolves, resulting in a significant decrease in their numbers, genetic diversity and gene flow between populations. For more effective protection and management of wolf populations in Europe, robust scientific evidence is crucial. This review serves as an analytical summary of the main findings from wolf population genetic studies in Europe, covering major studies from the ‘pre-genomic era’ and the first insights of the ‘genomics era’. We analyse, summarize and discuss findings derived from analyses of three compartments of the mammalian genome with different inheritance modes: maternal (mitochondrial DNA), paternal (Y chromosome) and biparental [autosomal microsatellites and single nucleotide polymorphisms (SNPs)]. To describe large-scale trends and patterns of genetic variation in European wolf populations, we conducted a meta-analysis based on the results of previous microsatellite studies and also included new data, covering all 19 European countries for which wolf genetic information is available: Norway, Sweden, Finland, Estonia, Latvia, Lithuania, Poland, Czech Republic, Slovakia, Germany, Belarus, Russia, Italy, Croatia, Bulgaria, Bosnia and Herzegovina, Greece, Spain and Portugal. We compared different indices of genetic diversity in wolf populations and found a significant spatial trend in heterozygosity across Europe from south-west (lowest genetic diversity) to north-east (highest). The range of spatial autocorrelation calculated on the basis of three characteristics of genetic diversity was 650−850 km, suggesting that the genetic diversity of a given wolf population can be influenced by populations up to 850 km away. As an important outcome of this synthesis, we discuss the most pressing issues threatening wolf populations in Europe, highlight important gaps in current knowledge, suggest solutions to overcome these limitations, and provide recommendations for science-based wolf conservation and management at regional and Europe-wide scales.

113 citations

Journal ArticleDOI
03 Oct 2012-PLOS ONE
TL;DR: This work demonstrates hybridization between wolf and dog populations in Estonia and Latvia, and the role of both genders in the hybridization process, and reveals the existence of dog mitochondrial genomes in the Latvian hybrids, providing the first evidence of mating between male wolves and female dogs.
Abstract: Studies on hybridization have proved critical for understanding key evolutionary processes such as speciation and adaptation. However, from the perspective of conservation, hybridization poses a concern, as it can threaten the integrity and fitness of many wild species, including canids. As a result of habitat fragmentation and extensive hunting pressure, gray wolf (Canis lupus) populations have declined dramatically in Europe and elsewhere during recent centuries. Small and fragmented populations have persisted, but often only in the presence of large numbers of dogs, which increase the potential for hybridization and introgression to deleteriously affect wolf populations. Here, we demonstrate hybridization between wolf and dog populations in Estonia and Latvia, and the role of both genders in the hybridization process, using combined analysis of maternal, paternal and biparental genetic markers. Eight animals exhibiting unusual external characteristics for wolves - six from Estonia and two from Latvia - proved to be wolf-dog hybrids. However, one of the hybridization events was extraordinary. Previous field observations and genetic studies have indicated that mating between wolves and dogs is sexually asymmetrical, occurring predominantly between female wolves and male dogs. While this was also the case among the Estonian hybrids, our data revealed the existence of dog mitochondrial genomes in the Latvian hybrids and, together with Y chromosome and autosomal microsatellite data, thus provided the first evidence from Europe of mating between male wolves and female dogs. We discuss patterns of sexual asymmetry in wolf-dog hybridization.

83 citations


Cited by
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Journal Article
Fumio Tajima1
30 Oct 1989-Genomics
TL;DR: It is suggested that the natural selection against large insertion/deletion is so weak that a large amount of variation is maintained in a population.

11,521 citations

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: The estimation of phylogenetic divergence times from sequence data is an important component of many molecular evolutionary studies, and a variety of local- and relaxed-clock methods have been proposed and implemented.
Abstract: The estimation of phylogenetic divergence times from sequence data is an important component of many molecular evolutionary studies. There is now a general appreciation that the procedure of divergence dating is considerably more complex than that initially described in the 1960s by Zuckerkandl and Pauling (1962, 1965). In particular, there has been much critical attention toward the assumption of a global molecular clock, resulting in the development of increasingly sophisticated techniques for inferring divergence times from sequence data. In response to the documentation of widespread departures from clocklike behavior, a variety of local- and relaxed-clock methods have been proposed and implemented. Local-clock methods permit different molecular clocks in different parts of the phylogenetic tree, thereby retaining the advantages of the classical molecular clock while casting off the restrictive assumption of a single, global rate of substitution (Rambaut and Bromham 1998; Yoder and Yang 2000).

770 citations

Journal ArticleDOI
19 Oct 2018-Science
TL;DR: Biodiversity-based techniques can be used to manage most human-modified lands as “working landscapes” and ensure that the production of food, fiber, fuel, and timber can be sustained over the long run and be more resilient to extreme events.
Abstract: How can we manage farmlands, forests, and rangelands to respond to the triple challenge of the Anthropocene-biodiversity loss, climate change, and unsustainable land use? When managed by using biodiversity-based techniques such as agroforestry, silvopasture, diversified farming, and ecosystem-based forest management, these socioeconomic systems can help maintain biodiversity and provide habitat connectivity, thereby complementing protected areas and providing greater resilience to climate change. Simultaneously, the use of these management techniques can improve yields and profitability more sustainably, enhancing livelihoods and food security. This approach to "working lands conservation" can create landscapes that work for nature and people. However, many socioeconomic challenges impede the uptake of biodiversity-based land management practices. Although improving voluntary incentives, market instruments, environmental regulations, and governance is essential to support working lands conservation, it is community action, social movements, and broad coalitions among citizens, businesses, nonprofits, and government agencies that have the power to transform how we manage land and protect the environment.

575 citations

Journal ArticleDOI
21 Apr 2017-Science
TL;DR: Many examples of conservation success show that losses can be halted and even reversed, and building on these lessons to turn the tide of biodiversity loss will require bold and innovative action to transform historical relationships between human populations and nature.
Abstract: Biodiversity is essential to human well-being, but people have been reducing biodiversity throughout human history. Loss of species and degradation of ecosystems are likely to further accelerate in the coming years. Our understanding of this crisis is now clear, and world leaders have pledged to avert it. Nonetheless, global goals to reduce the rate of biodiversity loss have mostly not been achieved. However, many examples of conservation success show that losses can be halted and even reversed. Building on these lessons to turn the tide of biodiversity loss will require bold and innovative action to transform historical relationships between human populations and nature.

528 citations