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.
Tracking, targeting, and conserving soil biodiversity Guerra, Carlos A; Bardgett, Richard D; Caon, Lucrezia ...
Science (American Association for the Advancement of Science),
2021-Jan-15, 2021-01-15, 20210115, Letnik:
371, Številka:
6526
Journal Article
Recenzirano
A monitoring and indicator system can inform policy
Nature conservation literature and policy instruments mainly focus on the impacts of human development and the benefits of nature conservation for ...oceans and aboveground terrestrial organisms (e.g., birds and plants) and processes (e.g., food production), but these efforts almost completely ignore the majority of terrestrial biodiversity that is unseen and living in the soil (
1
). Little is known about the conservation status of most soil organisms and the effects of nature conservation policies on soil systems. Yet like “canaries in the coal mine,” when soil organisms begin to disappear, ecosystems will soon start to underperform, potentially hindering their vital functions for humankind. Soil biodiversity and its ecosystem functions thus require explicit consideration when establishing nature protection priorities and policies and when designing new conservation areas. To inform such efforts, we lay out a global soil biodiversity and ecosystem function monitoring framework to be considered in the context of the post-2020 discussions of the Convention on Biological Diversity (CBD). To support this framework, we suggest a suite of soil ecological indicators based on essential biodiversity variables (EBVs) (
2
) (see the figure and table S3) that directly link to current global targets such as the ones established under the CBD, the Sustainable Development Goals (SDGs), and the Paris Agreement (table S1).
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.
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.
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.
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•Higher habitat suitability in the central area of the species’ distribution.•Demographic estimates indicated small population & threatened conservation status.•Very small percentage ...of highly suitable habitat is protected.•Most suitable patches are poorly connected.•Crucial connectivity paths are likely to be lost in future.
Muñoa’s pampas cat (recently proposed to be a distinct species, Leopardus munoai) is a small felid that is endemic to the Uruguayan Savanna ecoregion (encompassing southern Brazil, north-eastern Argentina and Uruguay). Previous studies have suggested that it is threatened, but its conservation assessment has been hampered by the scarcity of data on its ecology, including spatial distribution, population size, and connectivity. To address these issues, we developed current spatial distribution models and used them to: (i) identify the environmental variables affecting L. munoai habitat suitability; (ii) generate estimates of population size to assess its conservation status based on IUCN criteria; (iii) estimate habitat suitability in protected areas; (iv) identify potential paths of connectivity among protected areas and sites of confirmed occurrence; and (v) assess the proportion of the estimated connectivity paths that overlap with threatened areas (based on future threat projections). Our results indicated higher habitat suitability in the central area of the species’ distribution. All estimates (based on different demographic assumptions) indicated that L. munoai should be categorized in one of the IUCN threatened categories. Worryingly, several estimates indicated that it may be Critically Endangered. Only 0.73 % of its high-suitability landscape is presently protected, and connectivity among most protected areas and occurrence records was low. Additionally, areas with estimated connectivity among occurrence records mostly overlapped with regions with a high level of future habitat loss threat (92.46 %), highlighting the urgent need for an international approach to ensure the long-term survival of this elusive felid.
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.
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