scholarly journals Vertebrates on the brink as indicators of biological annihilation and the sixth mass extinction

2020 ◽  
Vol 117 (24) ◽  
pp. 13596-13602 ◽  
Author(s):  
Gerardo Ceballos ◽  
Paul R. Ehrlich ◽  
Peter H. Raven
Keyword(s):  
Ecosystem Services ◽  
Endangered Species ◽  
Mass Extinction ◽  
Life Support ◽  
Human Impacts ◽  
Bird Species ◽  
Wildlife Trade ◽  
Ecological Interactions ◽  
Terrestrial Vertebrates ◽  
Sixth Mass Extinction

The ongoing sixth mass species extinction is the result of the destruction of component populations leading to eventual extirpation of entire species. Populations and species extinctions have severe implications for society through the degradation of ecosystem services. Here we assess the extinction crisis from a different perspective. We examine 29,400 species of terrestrial vertebrates, and determine which are on the brink of extinction because they have fewer than 1,000 individuals. There are 515 species on the brink (1.7% of the evaluated vertebrates). Around 94% of the populations of 77 mammal and bird species on the brink have been lost in the last century. Assuming all species on the brink have similar trends, more than 237,000 populations of those species have vanished since 1900. We conclude the human-caused sixth mass extinction is likely accelerating for several reasons. First, many of the species that have been driven to the brink will likely become extinct soon. Second, the distribution of those species highly coincides with hundreds of other endangered species, surviving in regions with high human impacts, suggesting ongoing regional biodiversity collapses. Third, close ecological interactions of species on the brink tend to move other species toward annihilation when they disappear—extinction breeds extinctions. Finally, human pressures on the biosphere are growing rapidly, and a recent example is the current coronavirus disease 2019 (Covid-19) pandemic, linked to wildlife trade. Our results reemphasize the extreme urgency of taking much-expanded worldwide actions to save wild species and humanity’s crucial life-support systems from this existential threat.

scholarly journals Biological annihilation via the ongoing sixth mass extinction signaled by vertebrate population losses and declines

2017 ◽  
Vol 114 (30) ◽  
pp. E6089-E6096 ◽  
Author(s):  
Gerardo Ceballos ◽  
Paul R. Ehrlich ◽  
Rodolfo Dirzo
Keyword(s):  
Mass Extinction ◽  
Vertebrate Species ◽  
Population Declines ◽  
Mammal Species ◽  
Geographic Ranges ◽  
Terrestrial Vertebrates ◽  
Population Extinction ◽  
Population Loss ◽  
Sixth Mass Extinction ◽  
Species Extinctions

The population extinction pulse we describe here shows, from a quantitative viewpoint, that Earth’s sixth mass extinction is more severe than perceived when looking exclusively at species extinctions. Therefore, humanity needs to address anthropogenic population extirpation and decimation immediately. That conclusion is based on analyses of the numbers and degrees of range contraction (indicative of population shrinkage and/or population extinctions according to the International Union for Conservation of Nature) using a sample of 27,600 vertebrate species, and on a more detailed analysis documenting the population extinctions between 1900 and 2015 in 177 mammal species. We find that the rate of population loss in terrestrial vertebrates is extremely high—even in “species of low concern.” In our sample, comprising nearly half of known vertebrate species, 32% (8,851/27,600) are decreasing; that is, they have decreased in population size and range. In the 177 mammals for which we have detailed data, all have lost 30% or more of their geographic ranges and more than 40% of the species have experienced severe population declines (>80% range shrinkage). Our data indicate that beyond global species extinctions Earth is experiencing a huge episode of population declines and extirpations, which will have negative cascading consequences on ecosystem functioning and services vital to sustaining civilization. We describe this as a “biological annihilation” to highlight the current magnitude of Earth’s ongoing sixth major extinction event.

scholarly journals Thinking about the Biodiversity Loss in This Changing World

Geosciences ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 370
Author(s):  
Maria Rita Palombo
Keyword(s):  
Big Five ◽  
Mass Extinction ◽  
Negative Impact ◽  
Biodiversity Loss ◽  
Wildlife Trade ◽  
Ecosystem Structure ◽  
Extinction Rate ◽  
Mass Extinctions ◽  
Species Introduction ◽  
Sixth Mass Extinction

Extinction of species has been a recurrent phenomenon in the history of our planet, but it was generally outweighed in the course of quite a long geological time by the appearance of new species, except, especially, for the five geologically short times when the so-called “Big Five” mass extinctions occurred. Could the current decline in biodiversity be considered as a signal of an ongoing, human-driven sixth mass extinction? This note briefly examines some issues related to: (i) The hypothesized current extinction rate and the magnitude of contemporary global biodiversity loss; (ii) the challenges of comparing them to the background extinction rate and the magnitude of the past Big Five mass extinction events; (iii) briefly considering the effects of the main anthropogenic stressors on ecosystems, including the risk of the emergence of pandemic diseases. A comparison between the Pleistocene fauna dynamics with the present defaunation process and the cascading effects of recent anthropogenic actions on ecosystem structure and functioning suggests that habitat degradation, ecosystem fragmentation, and alien species introduction are important stressors increasing the negative impact on biodiversity exerted by anthropogenic-driven climate changes and their connected effects. In addition, anthropogenic ecological stressors such as urbanization, landscapes, and wildlife trade, creating new opportunities for virus transmission by augmenting human contact with wild species, are among the main factors triggering pandemic diseases.

scholarly journals Research on a Biodiversity Conservation Value Assessment Method Based on Habitat Suitability of Species: A Case Study in Gansu Province, China

2021 ◽  
Vol 13 (6) ◽  
pp. 3007
Author(s):  
Xiaojiong Zhao ◽  
Jian Wang ◽  
Junde Su ◽  
Wei Sun ◽  
Haoxian Meng
Keyword(s):  
Ecosystem Services ◽  
Endangered Species ◽  
Biodiversity Conservation ◽  
Gansu Province ◽  
Distribution Area ◽  
Suitable Habitat ◽  
Conservation Value ◽  
Value Assessment ◽  
Rare And Endangered Species ◽  
Rare And Endangered

Quantitative assessment and evaluation of ecological parameters and biodiversity conservation are prime concerns for long-term conservation of rare and endangered species and their associated habitats in any ecological region. In this study, Gansu Province, a biodiversity hotspot, was chosen as the research area. We predicted the distribution patterns of suitable habitats for rare and endangered species. The replacement cost method was adopted to calculate the conservation value of rare and endangered species. The suitable habitat distribution area of rare and endangered wild animals reached 351,607.76 km2 (without overlapping area), while that of plants reached 72,988.12 km2 (without overlapping area). The conservation value of rare and endangered wildlife is US $1670.00 million. The high-value areas are mostly concentrated in the south and north of Gansu Province. The conservation value of rare and endangered wild plants is US $56,920.00 million. The high-value areas are mostly concentrated south of Gansu Province. The conservation value is US $58,590.00 million a year, and its distribution trend is gradually decreasing from northeast to southwest, with the highest in the forest area south of Gansu Province, followed by the Qilian Mountain area in the north. These results are of great significance for future improvement of the evaluation index system of ecosystem services and the development of ecosystem services and management strategies.

scholarly journals Nepal’s National Red List of Birds

2017 ◽  
Vol 9 (1) ◽  
pp. 9700 ◽  
Author(s):  
Carol Inskipp ◽  
Hem Sagar Baral ◽  
Tim Inskipp ◽  
Ambika Prasad Khatiwada ◽  
Monsoon Pokharel Khatiwada ◽  
...  
Keyword(s):  
Endangered Species ◽  
Biological Diversity ◽  
Conservation Status ◽  
Bird Species ◽  
Convention On Biological Diversity ◽  
Wetland Birds ◽  
Distribution Maps ◽  
Critically Endangered Species ◽  
Passerine Species ◽  
Over Exploitation

The main objectives of the Nepal National Bird Red Data Book were to provide comprehensive and up-to-date accounts of all the bird species found in Nepal, assess their status applying the IUCN Guidelines at Regional Levels, identify threats to all bird species and recommend the most practical measures for their conservation.  It is hoped that the Bird RDB will help Nepal achieve the Convention on Biological Diversity target of preventing the extinction of known threatened species and improving their conservation status.  As population changes of Nepal’s birds have been studied for only a few species, assessments of species’ national status were mainly made by assessing changes in distribution.  Species distribution maps were produced for all of Nepal’s bird species except vagrants and compared to maps that were produced in 1991 using the same mapping system.  Of the 878 bird species recorded, 168 species (19%) were assessed as nationally threatened. These comprise 68 (40%) Critically Endangered species, 38 (23%) Endangered species and 62 (37%) Vulnerable species.  A total of 62 species was considered Near Threatened and 22 species Data Deficient.  Over 55% of the threatened birds are lowland grassland specialists, 25% are wetland birds and 24% tropical and sub-tropical broadleaved forest birds.  Larger birds appear to be more threatened than smaller birds with 98 (25%) non-passerine species threatened and 67 (14%) passerine species.  Habitat loss, degradation and fragmentation are the most important threats.  Other threats include chemical poisoning, over-exploitation, climate change, hydropower, invasive species, intensification of agriculture, disturbance, and limited conservation measures and research.  Measures to address these threats are described.  It was also concluded that re-assessments of the status of certain bird groups carried out every five years and the setting up of a national online system for storing and reporting bird sightings would be useful.

CITES-listed Wildlife Trade of the Czech Republic

2021 ◽  
Vol 13 (2) ◽  
pp. 2-8
Author(s):  
Nikola Sagapova ◽  
Radim Dusek
Keyword(s):  
International Trade ◽  
Czech Republic ◽  
Endangered Species ◽  
Plant Species ◽  
Wildlife Trade ◽  
Endangered Plants ◽  
The Czech Republic ◽  
Wildlife Species ◽  
Wild Fauna ◽  
Increasing Trend

Wildlife trade involves many animal and plant species and their products. CITES (Convention on International Trafe in Endangered Species of Wild Fauna and Flora) aims on protecting endangered plants and animals from being overharvested for the purposes of international trade through system of regulations, permits and monitoring. CITES Trade Database is a tool dedicated for the evidence of international trade of endangered wildlife species. We used records from the CITES Trade Database to conduct the analysis of the legal wildlife trade in the Czech Republic in the period 2008-2018. A total amount of 12,615 shipment records were extracted from CITES Trade Database. Amongst most imported taxons belong mammals (mostly genuses Ursus and Panthera) and reptiles (primarily genuses Varanus and Triocerus), while most exported taxons are birds (prevailing genuses Platycercus, Polytelis and Falco) and mammals (especially genus Lemur). While the export records showed an increasing trend, the imports were culminating around the average level of 642.3 records per year and lowest amount in the last year of the period. We emphasise smuggling of snowdrops and tigers and their products, which were reported to be seized, but with lack of records in legal trade.

The Green’s Gambit

2017 ◽  
Author(s):  
Benjamin Hale
Keyword(s):  
Ecosystem Services ◽  
Endangered Species ◽  
Moral Theory ◽  
Cost Benefit Analysis ◽  
Cost Benefit ◽  
Categorical Imperative ◽  
Endangered Species Act ◽  
Benefit Analysis ◽  
Ethical Considerations ◽  
Kantian Moral Theory

This chapter argues that reasons are underdetermined and often left out of value-based discussions of nature. The chapter offers a rough sketch of Kantian moral theory – particularly the first two formulations of the Categorical Imperative – to suggest that the primary charge of environmentalism ought to be that of encouraging deeper justification of actions. It utilizes the Endangered Species Act, the argument from ecosystem services, and the case of a stolen kidney to suggest that cost-benefit analysis and related methodologies are insufficient for addressing the broad ethical considerations of environmentalists.

Reducing the sixth mass extinction: Understanding the value of human-altered landscapes to the conservation of the world's largest terrestrial mammals

2020 ◽  
Vol 249 ◽  
pp. 108706 ◽  
Author(s):  
Erik Joaquín Torres-Romero ◽  
Anthony J. Giordano ◽  
Gerardo Ceballos ◽  
José Vicente López-Bao
Keyword(s):  
Mass Extinction ◽  
Terrestrial Mammals ◽  
Sixth Mass Extinction

scholarly journals Defaunation precipitates the extinction of evolutionarily distinct interactions in the Anthropocene

2019 ◽  
Vol 5 (6) ◽  
pp. eaav6699 ◽  
Author(s):  
Carine Emer ◽  
Mauro Galetti ◽  
Marco A. Pizo ◽  
Pedro Jordano ◽  
Miguel Verdú
Keyword(s):  
Seed Dispersal ◽  
Evolutionary History ◽  
Bird Species ◽  
Forest Fragments ◽  
Ecological Interactions ◽  
Rescue Effect ◽  
History Of ◽  
Local Extinctions ◽  
Functional Features ◽  
Avian Seed Dispersal

Species on Earth are interconnected with each other through ecological interactions. Defaunation can erode those connections, yet we lack evolutionary predictions about the consequences of losing interactions in human-modified ecosystems. We quantified the fate of the evolutionary history of avian–seed dispersal interactions across tropical forest fragments by combining the evolutionary distinctness of the pairwise-partner species, a proxy to their unique functional features. Both large-seeded plant and large-bodied bird species showed the highest evolutionary distinctness. We estimate a loss of 3.5 to 4.7 × 104 million years of cumulative evolutionary history of interactions due to defaunation. Bird-driven local extinctions mainly erode the most evolutionarily distinct interactions. However, the persistence of less evolutionarily distinct bird species in defaunated areas exerts a phylogenetic rescue effect through seed dispersal of evolutionarily distinct plant species.

scholarly journals Large-Scale Hybridisation as an Extinction Threat to the Suweon Treefrog (Hylidae: Dryophytes suweonensis)

Animals ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 764 ◽  
Author(s):  
Amaël Borzée ◽  
Jonathan J. Fong ◽  
Hoa Quynh Nguyen ◽  
Yikweon Jang
Keyword(s):  
Mitochondrial Dna ◽  
Species Distribution ◽  
Dna Sequences ◽  
Mass Extinction ◽  
Large Scale ◽  
Natural Habitats ◽  
Commensal Species ◽  
Polymorphic Microsatellites ◽  
Sixth Mass Extinction ◽  
Threaten Species

Amphibians are in the midst of a sixth mass extinction, and human activities play a major role in pushing species towards extinction. Landscape anthropisation has impacts that indirectly threaten species, in addition to the obvious destruction of natural habitats. For instance, land modification may bring human-commensal species in contact with sister-clades from which they were previously isolated. The species in these new contact zones are then able to hybridise to the point of reaching lineage fusion, through which the gene pool of the two species merges and one of the parental lineages becomes extirpated. Here, we documented the patterns of hybridisation between the spatially restricted D. suweonensis and the widespread D. japonicus. On the basis of the analysis of Cytochrome c oxidase subunit I mitochondrial DNA sequences (404 individuals from 35 sites) and six polymorphic microsatellites (381 individuals from 34 sites), we revealed a generalised, bi-directional, and geographically widespread hybridisation between the two species. Evidence of fertile back-crosses is provided by relatively high numbers of individuals in cyto-nuclear disequilibrium, as well as the presence of hybrid individuals further south than the species distribution limit, determined on the basis of call properties. Hybridisation is an additional threat to the endangered D. suweonensis.

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