Human activity has caused dramatic population declines in many wild species. The resulting bottlenecks have a profound impact on the genetic makeup of a species with unknown consequences for health. ...A key genetic factor for species survival is the evolution of deleterious mutation load, but how bottleneck strength and mutation load interact lacks empirical evidence. We analyze 60 complete genomes of six ibex species and the domestic goat. We show that historic bottlenecks rather than the current conservation status predict levels of genome-wide variation. By analyzing the exceptionally well-characterized population bottlenecks of the once nearly extinct Alpine ibex, we find genomic evidence of concurrent purging of highly deleterious mutations but accumulation of mildly deleterious mutations. This suggests that recolonization bottlenecks induced both relaxed selection and purging, thus reshaping the landscape of deleterious mutation load. Our findings highlight that even populations of ~1000 individuals can accumulate mildly deleterious mutations. Conservation efforts should focus on preventing population declines below such levels to ensure long-term survival of species.
Decades of overexploitation have devastated shark populations, leaving considerable doubt as to their ecological status
. Yet much of what is known about sharks has been inferred from catch records ...in industrial fisheries, whereas far less information is available about sharks that live in coastal habitats
. Here we address this knowledge gap using data from more than 15,000 standardized baited remote underwater video stations that were deployed on 371 reefs in 58 nations to estimate the conservation status of reef sharks globally. Our results reveal the profound impact that fishing has had on reef shark populations: we observed no sharks on almost 20% of the surveyed reefs. Reef sharks were almost completely absent from reefs in several nations, and shark depletion was strongly related to socio-economic conditions such as the size and proximity of the nearest market, poor governance and the density of the human population. However, opportunities for the conservation of reef sharks remain: shark sanctuaries, closed areas, catch limits and an absence of gillnets and longlines were associated with a substantially higher relative abundance of reef sharks. These results reveal several policy pathways for the restoration and management of reef shark populations, from direct top-down management of fishing to indirect improvement of governance conditions. Reef shark populations will only have a high chance of recovery by engaging key socio-economic aspects of tropical fisheries.
Bivalves are ubiquitous members of freshwater ecosystems and responsible for important functions and services. The present paper revises freshwater bivalve diversity, conservation status and threats ...at the global scale and discusses future research needs and management actions. The diversity patterns are uneven across the globe with hotspots in the interior basin in the United States of America (USA), Central America, Indian subcontinent and Southeast Asia. Freshwater bivalves are affected by multiple threats that vary across the globe; however, pollution and natural system (habitat) modifications being consistently found as the most impacting. Freshwater bivalves are among the most threatened groups in the world with 40% of the species being near threatened, threatened or extinct, and among them the order Unionida is the most endangered. We suggest that global cooperation between scientists, managers, politicians and general public, and application of new technologies (new generation sequencing and remote sensing, among others) will strengthen the quality of studies on the natural history and conservation of freshwater bivalves. Finally, we introduce the articles published in this special issue of
Hydrobiologia
under the scope of the Second International Meeting on Biology and Conservation of Freshwater Bivalves held in 2015 in Buffalo, New York, USA.
Archaeological and cultural heritage (ACH), one of the core carriers of cultural diversity on our planet, has a direct bearing on the sustainable development of mankind. Documenting and protecting ...ACH is the common responsibility and duty of all humanity. It is governed by UNESCO along with the scientific communities that foster and encourage the use of advanced non-invasive techniques and methods for promoting scientific research into ACH and conservation of ACH sites. The use of remote sensing, a non-destructive tool, is increasingly popular by specialists around the world as it allows fast prospecting and mapping at multiple scales, rapid analysis of multisource datasets, and dynamic monitoring of ACH sites and their surrounding environments. The cost of using remote sensing is lower or even zero in practical applications. In this review, in order to discuss the advantages of airborne and spaceborne remote sensing (ASRS), the principles that make passive (photography, multispectral and hyperspectral) and active (synthetic aperture radar (SAR) and light detection and ranging radar (LiDAR)) imaging techniques suitable for ACH applications are first summarized and pointed out; a review of ASRS and the methodologies used over the past century is then presented together with relevant highlights from well-known research projects. Selected case studies from Mediterranean regions to East Asia illustrate how ASRS can be used effectively to investigate and understand archaeological features at multiple -scales and to monitor and assess the conservation status of cultural heritage sites in the context of sustainable development. An in-depth discussion on the limitations of ASRS and associated remaining challenges is presented along with conclusions and a look at future trends.
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•A review of ACH applications in past 110 years of ASRS is performed.•Different ASRS techniques used for ACH application presented, including photography, spectral imaging, SAR and LiDAR.•Ground-truthing is the key to ASRS in ACH applications.•We finally point out the research trends that require further efforts.
Indicator species (IS) are used to monitor environmental changes, assess the efficacy of management, and provide warning signals for impending ecological shifts. Though widely adopted in recent years ...by ecologists, conservation biologists, and environmental practitioners, the use of IS has been criticized for several reasons, notably the lack of justification behind the choice of any given indicator. In this review, we assess how ecologists have selected, used, and evaluated the performance of the indicator species. We reviewed all articles published in Ecological Indicators (EI) between January 2001 and December 2014, focusing on the number of indicators used (one or more); common taxa employed; terminology, application, and rationale behind selection criteria; and performance assessment methods. Over the last 14 years, 1914 scientific papers were published in EI, describing studies conducted in 53 countries on six continents; of these, 817 (43%) used biological organisms as indicators. Terms used to describe organisms in IS research included “ecological index”, “environmental index”, “indicator species”, “bioindicator”, and “biomonitor,” but these and other terms often were not clearly defined. Twenty percent of IS publications used only a single species as an indicator; the remainder used groups of species as indicators. Nearly 50% of the taxa used as indicators were animals, 70% of which were invertebrates. The most common applications behind the use of IS were to: monitor ecosystem or environmental health and integrity (42%); assess habitat restoration (18%); and assess effects of pollution and contamination (18%). Indicators were chosen most frequently based on previously cited research (40%), local abundance (5%), ecological significance and/or conservation status (13%), or a combination of two or more of these reasons (25%). Surprisingly, 17% of the reviewed papers cited no clear justification for their choice of indicator. The vast majority (99%) of publications used statistical methods to assess the performance of the selected indicators. This review not only improves our understanding of the current uses and applications of IS, but will also inform practitioners about how to better select and evaluate ecological indicators when conducting future IS research.
Concerns about the rapid and severe declines of many bumble bee (Bombus spp.) species in Europe, and more recently North America, have spurred research into the extent and possible causes for these ...losses. Drawing conclusions has been difficult due to a lack of long-term data, especially for specific regions that may have different factors at play than the global trend. In this study, 150years of Bombus records in the state of New Hampshire from the University of New Hampshire Insect Collection were examined. This allowed for changes in abundance and distribution to be tracked over time, with focus on species designated of greatest conservation need by NH Fish & Game Department. Floral records also provided insight into the diet breadth of these species, which may affect their vulnerability. Evidence of drastic decline was found in Bombus affinis, Bombus fervidus, and Bombus terricola, as well as significant decline in Bombus vagans with data suggesting it has been ecologically replaced by Bombus impatiens over time. We suggest Bombus vagans receive future conservation consideration. Our analyses found a severe constriction of the geographic range of Bombus terricola to high elevation regions in the latter half of the 20th century, and its role as pollinator of several alpine plants necessitates immediate conservation action.
•We present an index that contrasts realised and potential ranges.•We modelled potential ranges that would exist in absence of human impacts.•Species with wider potential ranges may warrant higher ...conservation prioritisation.•Our index allows the status of species’ distributions to be assessed consistently.
Assessments of conservation status are typically based on short-term extinction risk, but the value of indicators that compare the current state of species (e.g., abundance or distribution) to potential baselines is increasingly recognised. The use of baselines in conservation legislation is hindered by ambiguity in how baselines should be determined and interpreted, leading to inconsistent application. Here, we explored the use of species’ potential ranges as a consistent means of quantifying baselines for assessing species’ distributions, a key component of conservation status. Using breeding birds of Great Britain (GB) as a case study, we simulated where bird species would be expected to occur today in a modelled world without human land use. We calculated indices that contrasted these potential human-free ranges with realised ranges. Our analyses revealed that 42% of GB birds have wider realised than potential ranges and 28% have narrower realised than potential ranges. These indices could lead to reassessments of current conservation priorities. Eighteen species assigned ‘least concern’ status by the GB regional IUCN Red List had much narrower realised than potential ranges, suggesting that their ranges are in a more degraded state than currently recognised by Red List criteria. Some of these species are not under active conservation management and could be candidates for higher prioritisation. Our approach provides a systematic means of quantifying range baselines that is not reliant on variable historic data or expert opinion and, thereby, provides a step forward in resolving a major contemporary problem in conservation assessment: how to set baselines in conservation consistently. The insights produced are also of wider scientific and cultural relevance, revealing where species would likely exist today in the absence of historic human impacts. This could be used to identify areas where targeted restoration actions might lead to the return of historically extirpated species, or even to novel colonists.
Summary
Bethencourtia Choisy (Compositae, Senecioneae) has three species and is dedicated to Jean IV de Béthencourt (1362—ca.1425/1426), who led the first successful military European expedition to ...conquer the Canary Islands. The botanical history of this Canary Island genus is reviewed, and its nomenclature is revisited. The generitype, Senecio palmensis C.Sm. = B. palmensis (C.Sm.) Choisy, is illustrated (t. 1058). The names S. palmensis and S. hermosae Pit. are lectotypified. Phylogenetic relationships, conservation status, systematics, phytochemistry, and ecogeographical patterns are discussed. A list of the herbarium specimens which have been studied is given.
Species conservation assessments using the criteria outlined by the International Union for the Conservation of Nature Red List can be compromised by limited data availability. Species-rich tropical ...plant taxa with numerous microendemics are particularly problematic. This study focusses on the Begonia flora of the Indonesian island of Sulawesi, comprised of 65 herbaceous species mainly found in rainforest habitats. Sixty-two species are Sulawesi endemics, including 20 species restricted to limestone karst landscapes. Forty-eight species are represented by fewer than 10 herbarium collections. Here, we outline and discuss an approach that, despite these data limitations, allows meaningful conservation assessments by integrating analyses of occurrences, data primarily based on remote sensing approaches, including forest landscape integrity, forest cover loss, and land cover, and extent of suitable habitat estimation. The results indicate that most Sulawesi Begonia species are narrow endemics whose rainforest habitats have substantially deteriorated in the last two decades: 27 species are assessed as Critically Endangered, 24 as Endangered, six as Vulnerable, five as Least Concern, and three species are Data Deficient. Conservation action, including extension of the protected area network in Sulawesi with emphasis on areas of old-growth forest and limestone karst landscapes, and strengthening of ex-situ living collections, is recommended.
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