How many bird extinctions have we prevented?

Considerable resources and efforts have been directed at biodiversity conservation in recent years, but measures of the success of conservation programmes have been limited. Based on information on population sizes, trends, threatening processes and the nature and intensity of conservation actions implemented during 1994–2004, we assessed that 16 bird species would have probably become extinct during this period if conservation programmes for them had not been undertaken. The mean minimum population size of these 16 species increased from 34 to 147 breeding individuals during 1994–2004. In 1994, 63% of them had declining populations but by 2004, 81% were increasing. Most of these species (63%) are found on islands. The principal threats that led to their decline were habitat loss and degradation (88%), invasive species (50%) and exploitation (38%), a pattern similar to that for other threatened species, but with exploitation and invasive species being relatively more important. The principal actions carried out were habitat protection and management (75% of species), control of invasive species (50%), and captive breeding and release (33%). The 16 species represent only 8.9% of those currently classified as Critically Endangered, and 1.3% of those threatened with extinction. Many of these additional species slipped closer to extinction during 1994–2004, including 164 that deteriorated in status sufficiently to be uplisted to higher categories of extinction risk on the IUCN Red List (IUCN, 2006). Efforts need to be considerably scaled up to prevent many more extinctions in the coming decades. The knowledge and tools to achieve this are available, but we need to mobilize the resources and political will to apply them.

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The changing fates of the world's mammals

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2011.0116 ◽

2011 ◽

Vol 366 (1578) ◽

pp. 2598-2610 ◽

Cited By ~ 109

Author(s):

Michael Hoffmann ◽

Jerrold L. Belant ◽

Janice S. Chanson ◽

Neil A. Cox ◽

John Lamoreux ◽

...

Keyword(s):

Captive Breeding ◽

Extinction Risk ◽

Conservation Status ◽

Iucn Red List ◽

Red List ◽

Mammal Species ◽

International Union ◽

The Status ◽

Conservation Actions ◽

In The Wild

A recent complete assessment of the conservation status of 5487 mammal species demonstrated that at least one-fifth are at risk of extinction in the wild. We retrospectively identified genuine changes in extinction risk for mammals between 1996 and 2008 to calculate changes in the International Union for Conservation of Nature (IUCN) Red List Index (RLI). Species-level trends in the conservation status of mammalian diversity reveal that extinction risk in large-bodied species is increasing, and that the rate of deterioration has been most accelerated in the Indomalayan and Australasian realms. Expanding agriculture and hunting have been the main drivers of increased extinction risk in mammals. Site-based protection and management, legislation, and captive-breeding and reintroduction programmes have led to improvements in 24 species. We contextualize these changes, and explain why both deteriorations and improvements may be under-reported. Although this study highlights where conservation actions are leading to improvements, it fails to account for instances where conservation has prevented further deteriorations in the status of the world's mammals. The continued utility of the RLI is dependent on sustained investment to ensure repeated assessments of mammals over time and to facilitate future calculations of the RLI and measurement against global targets.

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The dynamics underlying avian extinction trajectories forecast a wave of extinctions

Biology Letters ◽

10.1098/rsbl.2019.0633 ◽

2019 ◽

Vol 15 (12) ◽

pp. 20190633 ◽

Cited By ~ 7

Author(s):

Melanie J. Monroe ◽

Stuart H. M. Butchart ◽

Arne O. Mooers ◽

Folmer Bokma

Keyword(s):

Extinction Risk ◽

Population Decline ◽

Bird Species ◽

Iucn Red List ◽

Red List ◽

Extinction Rate ◽

Critically Endangered Species ◽

Extinction Rates ◽

Historical Times ◽

Risk Categories

Population decline is a process, yet estimates of current extinction rates often consider just the final step of that process by counting numbers of species lost in historical times. This neglects the increased extinction risk that affects a large proportion of species, and consequently underestimates the effective extinction rate. Here, we model observed trajectories through IUCN Red List extinction risk categories for all bird species globally over 28 years, and estimate an overall effective extinction rate of 2.17 × 10 −4 /species/year. This is six times higher than the rate of outright extinction since 1500, as a consequence of the large number of species whose status is deteriorating. We very conservatively estimate that global conservation efforts have reduced the effective extinction rate by 40%, but mostly through preventing critically endangered species from going extinct rather than by preventing species at low risk from moving into higher-risk categories. Our findings suggest that extinction risk in birds is accumulating much more than previously appreciated, but would be even greater without conservation efforts.

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Conservation status of the order Rodentia of Brazil: taxonomic and biogeographical patterns

Boletim do Museu Paraense Emílio Goeldi Ciências Naturais ◽

10.46357/bcnaturais.v15i3.234 ◽

2020 ◽

Vol 15 (3) ◽

pp. 535-556

Author(s):

Thomas Edward Lacher ◽

Shelby D. McCay ◽

Gledson Vigiano Bianconi ◽

Lilianna K. Wolf ◽

Nicolette S. Roach ◽

...

Keyword(s):

Atlantic Forest ◽

Spatial Data ◽

Extinction Risk ◽

Conservation Status ◽

Field Research ◽

Iucn Red List ◽

Species Of Conservation Concern ◽

The Family ◽

Conservation Actions ◽

Data Deficient

The Global Mammal Assessment (GMA) evaluates the risk of extinction for all species of mammals, providing important data on their status to national and global conservation agencies and conventions. We assessed all of the species of Brazilian rodents as part of the GMA activities of the International Union for the Conservation of Nature Species Survival Commission (IUCN SSC) Small Mammal Specialist Group. A total of 234 species were evaluated against the IUCN Red List Criteria and placed into one of eight categories. Although rodents do not have elevated extinction risk compared to mammals as a whole, several families of caviomorph rodents have high levels of either threat, data deficiency, or both. The family Echimyidae has a large number of species and one-third of those either are species of conservation concern or data deficient. The family Ctenomyidae also is of concern in this regard. There are also strong geographic patterns to threat and poor knowledge. The focal areas for conservation effort are the Atlantic Forest and the Cerrado, and for Data Deficient species Atlantic Forest, Cerrado, and Amazonia, in particular the eastern Amazon. The results highlight the need for targeted field research and the application of ecological and spatial data to the development of conservation actions.

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The live bird trade in Brazil and its conservation implications: an overview

Bird Conservation International ◽

10.1017/s095927091200010x ◽

2012 ◽

Vol 23 (1) ◽

pp. 53-65 ◽

Cited By ~ 62

Author(s):

RÔMULO ROMEU NÓBREGA ALVES ◽

JOSÉ RIBAMAR DE FARIAS LIMA ◽

HELDER FARIAS P. ARAUJO

Keyword(s):

Captive Breeding ◽

Bird Species ◽

Iucn Red List ◽

Wild Birds ◽

Human Populations ◽

Cultural Economic ◽

Conservation Implications ◽

Ecological Aspects ◽

Commercial Network ◽

Live Bird

SummaryBrazil’s rich biological and cultural diversity makes it an exceptional location for examining the commerce in live wild birds and its implications for conservation. This paper catalogues the live bird species being traded in Brazil, characterises the trade in these animals, and discusses the implications for avian conservation. In spite of being illegal, capturing and selling birds is still a very common practice in Brazil and involves many actors who make up part of a large commercial network that distributes wild animals to every corner of the country. Our survey revealed that at least 295 bird species are illegally sold as pets in Brazil, with estimates derived from this data pointing to a total of more than 400 species - about 23% of the number of extant bird species in the country. Of the bird species recorded, two were classified as “Critically Endangered”, nine as “Endangered”, six as “Vulnerable”, and 19 as “Near Threatened” according to the most recent IUCN Red List. Most of the species recorded in this study as being widely bought and sold (including on the international market) are not listed by CITES even though many of them are in fact threatened. In light of the widespread illegal trade in wild birds in Brazil and the conservation implications for the species involved, there is an urgent need for actions that can control these activities. Steps should be taken to address the illegal traffic directly and these must include monitoring, law enforcement, effective sentencing (including deterrent sentences), targeting end-users, captive breeding, and education at all levels, taking into account the cultural, economic, social, and ecological aspects of the human populations involved.

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No evidence for a loss of genetic diversity despite a strong decline in size of a European population of the Corncrake Crex crex

Bird Conservation International ◽

10.1017/s0959270919000327 ◽

2019 ◽

Vol 30 (2) ◽

pp. 260-266

Author(s):

YOAN FOURCADE ◽

DAVID S RICHARDSON ◽

JEAN SECONDI

Keyword(s):

Genetic Diversity ◽

Extinction Risk ◽

Bird Species ◽

European Population ◽

Grassland Bird ◽

Low Genetic Diversity ◽

Conservation Actions ◽

Constant Gene ◽

High Conservation ◽

Conservation Concern

SummaryThe preservation of genetic diversity is an important aspect of conservation biology. Low genetic diversity within a population can lead to inbreeding depression and a reduction in adaptive potential, which may increase extinction risk. Here we report changes in genetic diversity over 12 years in a declining population of the Corncrake Crex crex, a grassland bird species of high conservation concern throughout Europe. Despite a twofold demographic decline during the same period, we found no evidence for a reduction of genetic diversity. The gradual genetic differentiation observed among populations of Corncrake across Europe suggests that genetic diversity is maintained in western populations by constant gene flow from the larger and more productive populations in eastern Europe and Asia. The maintenance of genetic diversity in this species is an opportunity that may help the implementation of effective conservation actions across the Corncrake’s European range.

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A data-driven geospatial workflow to improve mapping species distributions and assessing extinction risk under the IUCN Red List

10.1101/2020.04.27.064477 ◽

2020 ◽

Author(s):

Ruben Dario Palacio ◽

Pablo Jose Negret ◽

Jorge Velásquez-Tibatá ◽

Andrew P. Jacobson

Keyword(s):

Extinction Risk ◽

Conservation Status ◽

Bird Species ◽

Species Distributions ◽

Iucn Red List ◽

Red List ◽

Data Driven ◽

Distribution Maps ◽

Distance Weighted ◽

Extinction Risk Assessment

ABSTRACTSpecies distribution maps are essential for assessing extinction risk and guiding conservation efforts. Here, we developed a data-driven, reproducible geospatial workflow to map species distributions and evaluate their conservation status consistent with the guidelines and criteria of the IUCN Red List. Our workflow follows five automated steps to refine the distribution of a species starting from its Extent of Occurrence (EOO) to Area of Habitat (AOH) within the species range. The ranges are produced with an Inverse Distance Weighted (IDW) interpolation procedure, using presence and absence points derived from primary biodiversity data. As a case-study, we mapped the distribution of 2,273 bird species in the Americas, 55% of all terrestrial birds found in the region. We then compared our produced species ranges to the expert-drawn IUCN/BirdLife range maps and conducted a preliminary IUCN extinction risk assessment based on criterion B (Geographic Range). We found that our workflow generated ranges with fewer errors of omission, commission, and a better overall accuracy within each species EOO. The spatial overlap between both datasets was low (28%) and the expert-drawn range maps were consistently larger due to errors of commission. Their estimated Area of Habitat (AOH) was also larger for a subset of 741 forest-dependent birds. We found that incorporating geospatial data increased the number of threatened species by 52% in comparison to the 2019 IUCN Red List. Furthermore, 103 species could be placed in threatened categories (VU, EN, CR) pending further assessment. The implementation of our geospatial workflow provides a valuable alternative to increase the transparency and reliability of species risk assessments and improve mapping species distributions for conservation planning and decision-making.

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Climatic change and extinction risk of two globally threatened Ethiopian endemic bird species

PLoS ONE ◽

10.1371/journal.pone.0249633 ◽

2021 ◽

Vol 16 (5) ◽

pp. e0249633

Author(s):

Andrew J. Bladon ◽

Paul F. Donald ◽

Nigel J. Collar ◽

Jarso Denge ◽

Galgalo Dadacha ◽

...

Keyword(s):

Climate Change ◽

Captive Breeding ◽

Extinction Risk ◽

Bird Species ◽

Maximum Temperature ◽

Southern Ethiopia ◽

Individual Species ◽

Range Restriction ◽

Risk Of Extinction ◽

Modelling Approaches

Climate change is having profound effects on the distributions of species globally. Trait-based assessments predict that specialist and range-restricted species are among those most likely to be at risk of extinction from such changes. Understanding individual species’ responses to climate change is therefore critical for informing conservation planning. We use an established Species Distribution Modelling (SDM) protocol to describe the curious range-restriction of the globally threatened White-tailed Swallow (Hirundo megaensis) to a small area in southern Ethiopia. We find that, across a range of modelling approaches, the distribution of this species is well described by two climatic variables, maximum temperature and dry season precipitation. These same two variables have been previously found to limit the distribution of the unrelated but closely sympatric Ethiopian Bush-crow (Zavattariornis stresemanni). We project the future climatic suitability for both species under a range of climate scenarios and modelling approaches. Both species are at severe risk of extinction within the next half century, as the climate in 68–84% (for the swallow) and 90–100% (for the bush-crow) of their current ranges is predicted to become unsuitable. Intensive conservation measures, such as assisted migration and captive-breeding, may be the only options available to safeguard these two species. Their projected disappearance in the wild offers an opportunity to test the reliability of SDMs for predicting the fate of wild species. Monitoring future changes in the distribution and abundance of the bush-crow is particularly tractable because its nests are conspicuous and visible over large distances.

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Population densities and conservation status of Norfolk Island forest birds

Bird Conservation International ◽

10.1017/s0959270912000081 ◽

2012 ◽

Vol 23 (3) ◽

pp. 271-282 ◽

Cited By ~ 1

Author(s):

GUY DUTSON

Keyword(s):

National Park ◽

Conservation Status ◽

Bird Species ◽

Iucn Red List ◽

Small Population ◽

Population Densities ◽

Point Counts ◽

Norfolk Island ◽

Population Sizes ◽

Line Transects

SummaryThree weeks of intensive surveys in Norfolk Island National Park in 2009 failed to find White-chested White-eye Zosterops albogularis and it was calculated that there was a less than 17% probability that a population of 10 birds had been overlooked. The last multi-observer record of this species was in 1978, and it is recommended that the species’ IUCN Red List status of “Critically Endangered” is tagged as “Possibly Extinct”. During these surveys, the population densities of seven bird species were calculated from 352 independent point counts. Causes of imprecision and bias were investigated, suggesting a small underestimation. Other species were recorded too infrequently, or their distributions were too biased, for analysis. The population densities of the extant endemic taxa were relatively high and suggest no current declines, and the population estimates were consistent with previous studies. This study recommends monitoring most species by point counts, or line transects if resources are limited, supplemented with specific monitoring of Tasman (Norfolk Island) Parakeet Cyanoramphus cookii, Pacific Robin Petroica multicolor, Southern Boobook Ninox novaeseelandiae and seabirds. Ongoing monitoring of these birds is needed to help inform management of the National Park and the island in general, given their small population sizes and their likely susceptibility to rat and cat predation, competition from alien species and drought.

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Red List Indices to measure the sustainability of species use and impacts of invasive alien species

Bird Conservation International ◽

10.1017/s095927090800035x ◽

2008 ◽

Vol 18 (S1) ◽

pp. S245-S262 ◽

Cited By ~ 47

Author(s):

Stuart H. M. Butchart

Keyword(s):

Invasive Species ◽

International Trade ◽

Alien Species ◽

Invasive Alien Species ◽

Extinction Risk ◽

Bird Species ◽

Biodiversity Loss ◽

Red List ◽

Negative Slope ◽

The Status

AbstractAfter habitat loss and degradation, the leading threats to biodiversity are over-exploitation and invasive alien species. For birds, newly synthesised data using the standard classification schemes for utilisation and threat types for the IUCN Red List allow novel analyses on the importance of these threats and permit the calculation of Red List Indices (RLIs) to show trends in the status of birds driven by these factors. At least 45.7% of extant bird species (4,561 species) are used by humans, principally for pets (37.0%) and for hunting for food (14.2%), but other uses include sport hunting, ornamentation and traditional medicine. Much of this use drives trade at an international scale, involving at least 3,337 species (33.9%, substantially higher than previous estimates), mostly for the pet trade. RLIs show that although successful control and management of use and trade have led to some species improving in status, this has been outweighed by the number of species deteriorating in status owing to unsustainable exploitation. Overall, the RLI showing trends in extinction risk driven by issues related to use shows a negative slope: human use of birds is currently unsustainable. Similarly, and of relevance to the Convention on the International Trade in Endangered Species (CITES), the RLI for internationally traded bird species showing trends in extinction risk driven by issues related to international trade is also declining: international trade remains a threat to the world's birds. Invasive species impact at least one third of the world's threatened bird species (398 species, 32.6%), with mammals being the most important (impacting 81.1%), particularly through predation by carnivores and rodents. The RLI illustrating impacts of invasive species shows that they are driving a deterioration in the status of the world's birds. RLIs for the impacts of use and invasive species will be important indicators to help track progress towards the target of significantly reducing biodiversity loss by 2010.

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How Threatened Is Scincella huanrenensis? An Update on Threats and Trends

Conservation ◽

10.3390/conservation1010005 ◽

2021 ◽

Vol 1 (1) ◽

pp. 58-72

Author(s):

Yucheol Shin ◽

Kevin R. Messenger ◽

Kyo Soung Koo ◽

Sang Cheol Lee ◽

Mian Hou ◽

...

Keyword(s):

Threatened Species ◽

Extinction Risk ◽

High Elevation ◽

Global Scale ◽

Iucn Red List ◽

Red List ◽

Republic Of China ◽

The Status ◽

Conservation Actions ◽

Dynamics Of Population

It is important to understand the dynamics of population size to accurately assess threats and implement conservation activities when required. However, inaccurate estimates are harming both the threat estimation process, and the resulting conservation actions. Here, we address the extinction threats to Scincella huanrenensis, a species described in the People’s Republic of China, but also occurring on the Korean peninsula. Estimating the threats to the species is not an easy task due to its unknown population status in the Democratic People’s Republic of Korea. Here we analysed the literature to acquire the known presence point for the species, along with datapoints originating from opportunistic field surveys, and employed habitat suitability models to estimate the range of the species. We then followed the categories and criteria of the IUCN Red List of Threatened Species to assess the extinction risk of the species. We found the species not to be fitting the threatened category at the global scale based on the range size, the only category for which enough data was available. We recommend the status of the species on the IUCN Red List of Threatened Species to be updated as it is now listed as critically endangered (CR), a listing fitting a national assessment for the People’s Republic (PR) of China. While this species is possibly less threatened than currently listed, this is not a genuine improvement, and specific conservation aspects should not be neglected due to its specialisation to medium to high elevation habitat.

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