Changes In Conservation Status Research Articles

Extinction risks and threats facing the freshwater fishes of Britain

Abstract Extinctions occur naturally in all environments, but rates have accelerated rapidly during the Anthropocene, especially in fresh water. Despite supporting many fish species of conservation importance, there has never been a formal assessment of their extinction risks in Britain, which has impeded their inclusion in relevant legislation and policy. This study therefore used the International Union for the Conservation of Nature (IUCN) Red List of Threatened Species™ Categories and Criteria to conduct the first systematic assessment of the extinction risks and threats facing the native freshwater and diadromous fishes of Britain. In addition, national assessments were produced for England, Scotland and Wales, reflecting the level at which environmental policy decisions are taken in Britain. Seven species were categorized as being threatened with extinction at the regional level, with European eel Anguilla anguilla and allis shad Alosa alosa classified as Critically Endangered, Atlantic salmon Salmo salar, vendace Coregonus albula and European whitefish Coregonus lavaretus classified as Endangered, and Arctic charr Salvelinus alpinus and twaite shad Alosa fallax classified as Vulnerable. In addition, burbot Lota lota was classified as Regionally Extinct, ferox trout Salmo ferox was categorized as Data Deficient, and 25 species were categorized as Least Concern. European sturgeon Acipenser sturio and houting Coregonus oxyrinchus, although probably native, qualified as only vagrants in fresh water, so were categorized as Not Applicable. The assessments provide objective baselines against which future changes can be determined, and a key evidence base to support policy and management decisions for the conservation of freshwater and diadromous fish species and their habitats in Britain. It is recommended that the assessments are repeated every 10 years, which would enable changes in conservation status, the effectiveness of policies and where targeted interventions may be required to be examined using the Red List Index.

Notable Changes in Conservation Status of Vultures in Uttar Pradesh, India: A Study Based on Occupancy and Habitat Modelling

Notable Changes in Conservation Status of Vultures in Uttar Pradesh, India: A Study Based on Occupancy and Habitat Modelling

Threatened to least concern and after: the Barnacle Goose Branta leucopsis in Latvia

In Latvia, the Barnacle Goose Branta leucopsis was, except for a period in the first half of the 19th century, reported to be rare or relatively rare from the late 18th century to about 2010. The marked change in conservation status from threatened in 1985 to least concern in 2000 was due to better knowledge about the situation at the Russian breeding grounds and had nothing to do with the occurrence in Latvia. Since the first flock ever of at least 100 individuals was observed in April 2007, the number of spring-staging birds has shown a steady increase. In 2021, numbers reached 5000 birds in the Svēte flood-plain staging area and more than 10 000 in the country as a whole. Numbers were lower in autumn. There are no recoveries or re-sightings of marked individuals indicating the origin of the staging birds. The increase in numbers in Latvia coincided with a marked decline in importance of the islands in the Baltic Sea for breeding and spring-staging Barnacle Geese.

Habitat association and population size of the Madeira Firecrest (Regulus madeirensis)

Basic population information is often lacking for recently recognized species, yet such information is essential for conservation and management. This study provides a detailed assessment of population size and habitat association in the Madeira Firecrest (Regulus madeirensis). Species abundance and habitat data were collected using a point transect distance sampling method. Estimates of density per habitat type were made, in conjunction with presence and absence data derived from the Madeira bird atlas, to estimate population size and habitat associations. We estimate the population size of the Madeira Firecrest to be 698,300 (95% CI: 523,540–869,960), which greatly exceeds the 10,000 individuals threshold for the IUCN “Vulnerable” category. Distribution and abundance were strongly associated with laurel and heath forest, with 56% of the population found in these 2 habitats. Historically, much of the native laurel and heath forest was lost on Madeira, but these remnant native forest habitats are now protected. Based on the large population size and successful management of the laurel forest habitat, our results suggest there is no immediate risk of a change in conservation status for the Madeira Firecrest.

Habitat association and population size of the Madeira Firecrest (Regulus madeirensis)

Basic population information is often lacking for recently recognized species, yet such information is essential for conservation and management. This study provides a detailed assessment of population size and habitat association in the Madeira Firecrest (Regulus madeirensis). Species abundance and habitat data were collected using a point transect distance sampling method. Estimates of density per habitat type were made, in conjunction with presence and absence data derived from the Madeira bird atlas, to estimate population size and habitat associations. We estimate the population size of the Madeira Firecrest to be 698,300 (95% CI: 523,540–869,960), which greatly exceeds the 10,000 individuals threshold for the IUCN “Vulnerable” category. Distribution and abundance were strongly associated with laurel and heath forest, with 56% of the population found in these 2 habitats. Historically, much of the native laurel and heath forest was lost on Madeira, but these remnant native forest habitats are now protected. Based on the large population size and successful management of the laurel forest habitat, our results suggest there is no immediate risk of a change in conservation status for the Madeira Firecrest.

Integrating species pools and abundance distribution in habitat conservation status assessment: A new index

Habitat degradation and fragmentation are recognized as major causes of biodiversity loss, and effective management to conserve habitats is highly dependent on our ability to assess their conservation status. In this study we introduce a new index (VCS, for vegetation conservation status) to assess the conservation status of plant communities, which reflect the identity of habitat types. The VCS index is based on the same probabilistic approach than the classical Simpson’s diversity index, but uses the concept of species pools to integrate the influence of ‘typical’ and ‘non-typical’ species on habitat conservation status. In addition to the effect of species identity, this index also allows the detection of change in conservation status because of variation in species-abundance distribution. As an example we applied the VCS index to two heathland habitats in French Brittany and we compared the values provided by the index to qualitative assessments by heathland experts. We also compared the performance of the VCS index against three other indices: species richness, species diversity and a more recent index of ‘favourable conservation status’. Among the four indices tested, the VCS index was the most effective in assessing the vegetation conservation status when compared against qualitative assessment by heathland experts. Moreover the VCS index, coupled with variance partitioning methods, allowed to quantify the contribution of expected causes of habitat degradation. This study demonstrates that the use of habitat-specific species pools to distinguish between typical and non-typical species, as well as the consideration of species abundances, are critical for an accurate assessment of the vegetation conservation status. The VCS index should therefore be a valuable tool for both managers and researchers involved in habitat conservation.

Iucn_sim: a new program to simulate future extinctions based on IUCN threat status

The ongoing environmental crisis poses an urgent need to forecast the who, where and when of future species extinctions, as such information is crucial for targeting conservation efforts. Commonly, such forecasts are made based on conservation status assessments produced by the International Union for Conservation of Nature (IUCN). However, when researchers apply these IUCN conservation status data for predicting future extinctions, important information is often omitted, which can impact the accuracy of these predictions.Here we present a new approach and a software for simulating future extinctions based on IUCN conservation status information, which incorporates generation length information of individual species when modeling extinction risks. Additionally, we explicitly model future changes in conservation status for each species, based on status transition rates that we estimate from the IUCN assessment history of the last decades. Finally, we apply a Markov chain Monte Carlo algorithm to estimate extinction rates for each species, based on the simulated future extinctions. These estimates inherently incorporate the chances of conservation status changes and the generation length for each given species and are specific to the simulated time frame.We demonstrate the utility of our approach by estimating future extinction rates for all bird species. Our average extinction rate estimate for the next 100 yr across all birds is 6.98 × 10−4 extinctions per species‐year, and we predict an expected biodiversity loss of between 669 and 738 bird species within that time frame. Further, the rate estimates between species sharing the same IUCN status show larger variation than the rates estimated with alternative approaches, which reflects expected differences in extinction risk among taxa of the same conservation status. Our method demonstrates the utility of applying species‐specific information to the estimation of extinction rates, rather than assuming equal extinction risks for species assigned to the same conservation status.

Conservation status of Stenostelma umbelluliferum and its implications for management of biodiversity

Stenostelma umbelluliferum is an enigmatic plant that has elicited much attention in recent years. Initially thought to be extinct, its rediscovery in an urban area created turmoil in both conservation management and urban development. Taxonomic and field investigations were conducted over a number of years to gain a more comprehensive understanding of the species, and each new batch of information lead to conservation status changes. A re-assessment of the conservation status is presented, based on the most recent evidence of its distribution, threats and population dynamics.

Trade‐offs between fire hazard reduction and conservation in a Natura 2000 shrub–grassland mosaic

AbstractQuestionsWhat are the effects of time since prescribed burning on plant species composition and diversity in a Natura 2000 shrub–grassland mosaic? Is it possible to use prescribed burning to reduce fire hazard and simultaneously maintain conservation status in such habitat types?LocationSintra‐Cascais Natural Park, Portugal.MethodsWe assessed differences in plant species composition, plant diversity, vegetation structure and above‐ground plant biomass between plots treated with prescribed burning (two, four and six years after fire) and untreated plots in a mosaic of Natura 2000 dry shrub–grasslands, and assessed potential fire behaviour differences between treatments.ResultsPlant species richness and diversity were higher two and four years after prescribed burning, in comparison with untreated plots. Cover of herbaceous species and non‐resprouters was higher, and cover of shrubs was lower, but only two years after fire. Habitat structure and phytovolume of the indicator species Ulex jussiaei was affected negatively up to six years after prescribed burning, indicating changes in conservation status from Favourable to Unfavourable. Prescribed burning reduced above‐ground biomass and fire simulations showed that potential fire hazard was also reduced, particularly in two‐year‐old plots.ConclusionsPrescribed burning increased plant diversity in the short term, reduced fuel loads and fire hazard, but negatively affected habitat conservation status. We show that there are potential trade‐offs between fire hazard mitigation and conservation in a Natura 2000 shrub–grassland habitat type and that these must be considered during fuel management decisions.

Principal threats to the conservation of freshwater habitats in the continental biogeographical region of Central Europe

In this paper, we discuss the threats to freshwater habitats that are highly important to the European Community in the Continental Biogeographical Region of Europe, specifically in Poland. The study covers nine freshwater habitat types distinguished in Natura 2000, Annex I of the Habitats Directive, which is a network of nature protection areas in the territory: standing water bodies (3110, 3130, 3140, 3150, and 3160) and running water (3260, 3220, 3240, and 3270), occurring in 806 Special Areas of Conservation in Poland. Of the 72,673 km2 total area of freshwater habitat covered by Natura 2000 in Poland, only 25.70% was classified, from the period 2006‒2018, as favourable status, whereas 68.72% was classified as unfavourable inadequate or unfavourable bad status. Based on a multivariate analysis, we found that significant differences in the conservation status of freshwater habitats resulted from a variety of threats, pressures, and activities, among which the most significant are urbanization and residential and commercial development; transportation and service corridors; decreased and unstable water resources; fishing and harvesting of aquatic resources; agricultural pollution; improper management and use of the agricultural catchment and forest catchment; changes in biocenotic evolution, invasive species succession, and more intense touristic exploration. The changes in conservation status of habitats 3110, 3130, 3140, 3160, and 3260 are also associated with climate change. Taking into account the threats identified, a list of recommended practices for the freshwater habitat types is presented, to be considered in habitat conservation programmes.

Temporal changes in abundance-occupancy relationships over 40years.

Abundance–occupancy (A–O) relationships are widely documented for many organismal groups and regions, and have been used to gain an understanding of regional population and community trends. Monitoring changes in abundance and occupancy over time may be what is required to document changes in conservation status and needs for some species, communities, or areas.We hypothesize that if there is a higher proportion of declining species in one group of species compared with another (e.g., migratory species vs. permanent residents), then a consequence of that difference will be vastly different abundance–occupancy relationships. If this difference persists through time, then the resulting A–O relationships between the groups will continue to diverge.For neotropical migrants, short‐distance migrants, and permanent resident birds of North America, we assess the numbers of declining species over 1969–2009. We further test for differences in the A–O relationship across these three groups, and in rates of change in abundance and occupancy separately.We find significant differences in numbers of declining species across the migratory groups, a significant decline in the A–O relationship for permanent residents, a significant increase for Neotropical migrants, and a nonsignificant decline for short‐distance migrants over the 40 years. Further, abundances are not changing at different rates but occupancies are consistently greater over time for neotropical migrants versus permanent residents, likely driving the changes in A–O relationships observed.In these analyses, we documented changing A–O trends for different groups of species, over a relatively long time period for ecological studies, one of only a few studies to examine A–O relationships over time. Further, we have shown that a temporally unvarying abundance–occupancy relationship is not universal, and we posit that variability in A–O relationships is due to human impacts on habitats, coupled with variation in species' abilities to respond to human impacts.

Embracing conservation success of recovering humpback whale populations: Evaluating the case for downlisting their conservation status in Australia

Optimism and hope in conservation biology are supported by examples of endangered species recovery, such as the population growth observed in humpback whales in several of the world׳s oceans. In Australia, monitoring data suggest rapid recovery for both east and west coast populations, which are now larger than 50% of their pre-whaling abundance. The measured growth rates exceed known species trends worldwide and have no indication of diminishing. Under Australian Commonwealth legislation and regulations, these populations should be considered for downlisting, as they are not eligible for listing as a threatened species against all statutory criteria. A change in conservation status will produce new challenges for the conservation and management of a recovered species, especially with the Australian economic landscape experiencing large-scale growth and development in recent years. More importantly, a recovered humpback whale population may bring a positive shift in the research goals and objectives throughout Australia by ensuring other endangered species an equal chance of recovery while delivering hope, optimism, and an opportunity to celebrate a conservation success.

The sampled Red List Index for plants, phase II: ground-truthing specimen-based conservation assessments.

The IUCN Sampled Red List Index (SRLI) is a policy response by biodiversity scientists to the need to estimate trends in extinction risk of the world's diminishing biological diversity. Assessments of plant species for the SRLI project rely predominantly on herbarium specimen data from natural history collections, in the overwhelming absence of accurate population data or detailed distribution maps for the vast majority of plant species. This creates difficulties in re-assessing these species so as to measure genuine changes in conservation status, which must be observed under the same Red List criteria in order to be distinguished from an increase in the knowledge available for that species, and thus re-calculate the SRLI. However, the same specimen data identify precise localities where threatened species have previously been collected and can be used to model species ranges and to target fieldwork in order to test specimen-based range estimates and collect population data for SRLI plant species. Here, we outline a strategy for prioritizing fieldwork efforts in order to apply a wider range of IUCN Red List criteria to assessments of plant species, or any taxa with detailed locality or natural history specimen data, to produce a more robust estimation of the SRLI.

The fate of hydnoid fungi in The Netherlands and Northwestern Europe

Changes in frequency of sporocarps of hydnoid fungi in The Netherlands since 1950 are analysed using several methods. All 22 native species show a significant decrease from 1950 onwards. For 12 species associated with Fagus and Quercus a partial recovery since 1998 is demonstrated. Among 10 species associated with Pinus nine have become extinct and no recovery is observed so far. Changes in conservation status of all species are described. The causes of changing frequencies are discussed, being mainly related to amounts of deposited nitrogen. The different reactions of symbionts of deciduous and coniferous trees are explained. The status of hydnoid fungi in The Netherlands is compared with the situation in Belgium, Germany and Sweden.

A Conservation Action Plan for the Mentawai Primates

In this Conservation Action Plan, I evaluate the status of and make conservation recommendations for the four endemic primates of the Mentawai Islands: Kloss's gibbon (Hylobates klossii primates of the Mentawai Islands: Kloss's gibbon (Hylobates klossii primates of the Mentawai Islands: Kloss's gibbon ( ), the simakobu monkey (Simias concolor), the Mentawai langur (Presbytis potenziani langur (Presbytis potenziani langur ( ), and the Mentawai macaque (Macaca pagensis). There are two subspecies of each of the cercopi- thecines. They are threatened mainly by hunting and commercial logging. This action plan follows up on the recommendations made for the Mentawai primates in the IUCN/SSC Primate Specialist Group's Action Plan for Asian Primate Conservation: 1987-91 by Ardith Eudey, and includes data and recommendations from researchers who have studied them since 1980. I also include a brief history of conservation action in the Mentawai Islands to put these recommendations in a historical context. I recommend the following conservation status changes: Kloss's gibbon, Endangered; simakobu monkey, Critically Endangered; Mentawai langur, Endangered; and Mentawai macaque, Vulnerable. The largest populations of the four species can be found in Siberut National Park on the largest and northernmost island, but all but Kloss's gibbon have distinct subspecies on the southern islands of Sipora, North Pagai, and South Pagai, and these are urgently in need of protective measures. The national park is remote and diffi cult to access by researchers and tourists. I suggest the following conservation actions: 1) increased protection for the Siberut National Park, which currently lacks enforcement; 2) formal protection of the Peleonan forest in North Siberut, which is home to unusually high primate populations and is easily accessible; 3) protect areas in the Pagai Islands by cooperating with a logging corporation that has practiced sustainable logging techniques there since 1971; 4) conservation education, especially regarding hunting; and 5) the development of alternative economic models for the local people to reduce the likelihood of selling

Are listed threatened plant species actually at risk?

Despite the fact that the most changes in lists of threatened species reflect changes in knowledge rather than changes in conservation status, the lists continue to provide social and legal mandates for conservation; they are used to report on the state of the environment and to guide the allocation of scarce resources. There is a substantial under-representation of non-vascular species in threatened plant lists, reflected in an absence of documented extinctions among fungi and algae. Turnover in the composition of extinct flora lists in Australia suggests that the lists of threatened species may not be sufficiently reliable to form the basis for reporting on the state of the environment. They are of limited use in distinguishing between levels of threat and may not be a reliable guide for the allocation of scarce conservation resources among plant species. Systems for listing threatened species create a feedback loop, responsive to the subjective preferences of scientists, largely unresponsive to underlying true threats, self-perpetuating and accentuating bias with each iteration. Other tools, including formal decision approaches and the acquisition of new kinds of data, are needed to fill the roles.

Corrigendum to: TURNER REVIEW No. 5: Are listed threatened plant species actually at risk?

Despite the fact that the most changes in lists of threatened species reflect changes in knowledge rather than changes in conservation status, the lists continue to provide social and legal mandates for conservation; they are used to report on the state of the environment and to guide the allocation of scarce resources. There is a substantial under-representation of non-vascular species in threatened plant lists, reflected in an absence of documented extinctions among fungi and algae. Turnover in the composition of extinct flora lists in Australia suggests that the lists of threatened species may not be sufficiently reliable to form the basis for reporting on the state of the environment. They are of limited use in distinguishing between levels of threat and may not be a reliable guide for the allocation of scarce conservation resources among plant species. Systems for listing threatened species create a feedback loop, responsive to the subjective preferences of scientists, largely unresponsive to underlying true threats, self-perpetuating and accentuating bias with each iteration. Other tools, including formal decision approaches and the acquisition of new kinds of data, are needed to fill the roles.

Application of IUCN criteria and Red List categories to species of five Anacardiaceae genera in Madagascar

The conservation status of five genera of Anacardiaceae in Madagascarwas determined by applying IUCN risk assessment criteria to recent taxonomicrevisions and available specimen data. A major problem in establishing protocolsfor efficiently protecting and conserving Madagascar's biodiversity is the lackof essential biological information. In light of this, primary occurrence dataappears to be an invaluable tool for assessing both current and historic speciesdistributions. GIS technology was used to create species distribution maps forhistoric vs. recent occurrence data to analyze the change in conservationstatus, extent of occurrence, and area of occupancy for each of the targetspecies. A GAP analysis reveals that 14 (100%) of the target species for whichdata were available are considered threatened by IUCN standards. Furthermore, 11(79%) species showed a decrease both in the number of subpopulations and theirextent of occurrence when compared to historic distributions. This studyhighlights the importance of two factors necessary to address modernconservation questions. Sound conclusions regarding the conservation status ofindividual species requires a strong taxonomic framework and good collectiondata for a species distribution. However, because specimen data are very oftenincomplete and biased both geographically and taxonomically, reaching soundconclusions requires field knowledge of individual species to compensate forthese limitations.

Inferring Threat from Scientific Collections

Exact formulas for the probability of extinction or change in the conservation status of species are described for data based on frequency of sighting. These formulas generalize an expression previously described for the probability of extinction from (binary) sighting data. The formulas will be used in contexts where sightings are recorded as frequencies, such as when observations are aggregated in time. We argue that computing the probability of extinction or change in conservation status will be most useful for setting conservation priorities and in screening large data sets contained in museum and herbarium collections and in biological resource inventories.

Eye movements, perceptual activity, and conservation development

A rationale for interpreting eye movement patterns (EMPs) in children varying in stages of conservation development was derived from the theoretical positions of Piaget, Bruner, and Wohlwill. Ninety-two girls, 6–10 years of age, were tested on Piagetian conservation tasks including length, area, and continuous quantity (solid and liquid). Corneally reflected eye movements were recorded on these tasks from the point immediately following the conservation question until Ss responded. After testings Ss were classified according to Piagetian procedure into nonconservers (NC1), transitional nonconservers (NC2), and conservers (C). Results indicated substantial EMP differences between conservers and nonconservers, as well as between the nonconserver groups. Moreover, the data appear to support a theory of perceptual activity leading to decentration and to indicate a change in viewing strategy associated with change in conservation status.