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Biodiversity is in rapid decline, but the extent of loss is not well resolved for poorly known groups. We estimate the number of extinctions for Australian non-marine invertebrates since the European colonisation of the continent. Our analyses use a range of approaches, incorporate stated uncertainties and recognise explicit caveats. We use plausible bounds for the number of species, two approaches for estimating extinction rate, and Monte Carlo simulations to select combinations of projected distributions from these variables. We conclude that 9,111 (plausible bounds of 1,465 to 56,828) Australian species have become extinct over this 236-year period. These estimates dwarf the number of formally recognised extinctions of Australian invertebrates (10 species) and of the single invertebrate species listed as extinct under Australian legislation. We predict that 39–148 species will become extinct in 2024. This is inconsistent with a recent pledge by the Australian government to prevent all extinctions. This high rate of loss is largely a consequence of pervasive taxonomic biases in community concern and conservation investment. Those characteristics also make it challenging to reduce that rate of loss, as there is uncertainty about which invertebrate species are at the most risk. We outline conservation responses to reduce the likelihood of further extinctions.
A natural population of Vriesea friburgensis var. paludosa was genetically and demographically characterized. Four selected enzymatic systems were used. In total, 10 allozymic loci were analysed. The proportion of polymorphic loci was 70% and the number of alleles per locus was 2.3· The mean observed and expected heterozygosities were 0.234 and 0.226, respectively. An excess of heterozygotes was revealed by the value of the fixation index (—0.035). These indices showed the presence of high levels of genetic diversity in the population studied. A demographic survey revealed almost six times more vegetative than sexually reproductive plants. Reproductive plants were found only in clusters. The genetic diversity exhibited by this population, associated with vegetative as well as sexual propagation, resulting in clusters or colonies, would allow the employment of a sustainable management strategy for species conservation as well as its exploitation as an ornamental.
The technique of excised embryos was employed to facilitate the propagation of Podophyllum emodi derived from seeds collected at the different elevation zones of Himachal Pradesh, India. Seed germination was low, irrespective of stage of seed development or zone of collection. Germination was improved significantly (89.14%) in the partially mature and mature seeds collected from alpine and temperate zones when excised embryos were cultured on basal B5 medium. Leaf emergence and plant establishment in the field was also significantly higher in the plants raised through this technique, despite hypocotyl dormancy. The technique was successfully employed for the production of plants to be reintroduced in large numbers into their habitat in the Great Himalayan National Park.
The grasslands of Central Anatolia in Türkiye, including the steppes and forest-steppes, are often mischaracterized as degraded ecosystems due to long-standing human activities, particularly agriculture and domestic grazing. However, palaeoecological evidence and recent research suggest that these grasslands are ancient, biodiversity-rich systems that have persisted through various climatic changes and disturbance regimes. This manuscript challenges the conventional view that Central Anatolian grasslands are secondary and degraded, arguing instead that they represent old-growth ecosystems that coexisted with forests as alternative biome states throughout history. We emphasize the need to re-evaluate current land management practices, particularly afforestation efforts, which may undermine the resilience of these ecosystems to climate change. By recognizing the ecological value of these old-growth grasslands and adopting a comprehensive conservation strategy, the conservation and restoration of these vital ecosystems can be improved, ensuring their resilience and biodiversity in the face of future environmental challenges.
A new way of thinking about environmental problems has emerged since the 1980s. Environmental problems are increasingly seen as systematically entwined, with human action as their primary cause. We are in a new epoch in Earth’s history, the Anthropocene, and climate change is its most immediate and dramatic manifestation. The drivers of the Anthropocene can be seen through the lens of a simple equation: Environmental impact is the product of population, affluence, and technology. Nations and individuals vary greatly in their impacts, so questions of justice are unavoidable. Questions of justice extend across generations as well as among nations and individuals. Ultimately, we must ask what kind of world we want for ourselves and our children.
Contrary to the common perception of hyperarid drylands as barren and lifeless, these regions are home to some of the planet’s most unique biodiversity and support over 100 million people. Despite their ecological and human significance, hyperarid drylands remain among the least studied biomes in the world. In this article, we explore how improving our understanding of hyperarid ecosystems in the Middle East can yield valuable insights applicable to other hyperarid regions. We examine how ongoing greening initiatives in the Middle East offer a unique opportunity to deepen our knowledge of dryland ecology and advocate for the establishment of a comprehensive research program in the region. This program would focus on ecosystem functionality across spatial and temporal scales, setting the stage for a global monitoring network for hyperarid drylands. Such efforts would inform conservation strategies and climate change mitigation, while also shedding light on the resilience and adaptability of hyperarid ecosystems to environmental change. Ultimately, this monitoring would guide management practices to preserve biodiversity, enhance ecosystem services and promote sustainable development in hyperarid regions worldwide.
This chapter examines the published work and careers of American conservationist William Vogt and Brazilian physician-geographer Josué de Castro during the early Cold War. It emphasizes the different affective strategies that the two men employed to persuade readers of their competing positions regarding the relationship between human population, arable land, food supply, and global security. As a briefly prominent intellectual from the global South, De Castro challenged the emerging, US-led consensus that population control was essential for economic development. Based on his own experiences among marginalized Brazilians, De Castro viewed Vogt’s concern with “carrying capacity” limits as an imperialist imposition on the autonomy of less empowered people. He feared that prioritizing population reduction as the solution to resource scarcity would undermine movements for social and economic transformation, such as agrarian reform in rural Latin America. With little personal experience of the world’s poor, Vogt projected a pessimistic vision of the future on continents overrun by desperate, starving hordes. De Castro’s contrasting vision, on the other hand, stemmed from frequent encounters with the chronically hungry and a more sympathetic understanding of their plight.
Seahorses Hippocampus spp. are commercially and culturally important to many communities. Although seahorses are widely used in traditional medicine, as curios and as aquarium fishes in Southeast Asia, documentation on the current nature and extent of culturally motivated seahorse uses in Malaysia is lacking. To examine how ethnicity and other socio-demographic drivers shape traditional medicinal use and underlying cultural beliefs involving seahorses, we administered a questionnaire-based survey during March 2021–April 2022 to members of the general public and fishers in Malaysia. Approximately one-fifth (21.0%) of respondents reported consuming seahorses (34.4% of these used seahorses for medicinal purposes, 55.2% for other non-medicinal uses and 10.4% for both types). Consumers of seahorses were from all ethnic groups except for Indigenous groups. In the general public group, medicinal use was more common amongst the Chinese respondents, whereas in the fisher group, other uses were more common amongst the Malay respondents. Amongst the threats facing seahorses, which include overfishing, habitat destruction, bycatch and ocean plastic pollution, only bycatch was perceived as a major threat by most of the general public and fisher respondents. The relatively low prevalence of reported seahorse use amongst Malaysians is an encouraging finding from a conservation perspective. However, the high proportion of non-medicinal uses indicates the need to focus on such other uses to ensure the sustainability of seahorse use in Malaysia.
The additionality of forest conservation interventions is frequently questioned. In particular, they are often considered to be located in places where forests are not threatened, which points to the existence of location biases. Revisiting this location bias concept, we conceptually distinguish potential and effective additionality and theoretically consider how the objectives of the implementer affect the siting choice of the forest conservation interventions and their additionality. Our theoretical intuition is that the choices of the implementers are influenced by the quality of institutions. Our results show that (1) the implementer's objective and local institutions may lead the implementer to select a site with low development potential and low forest threat, and (2) the selection of a site with low development potential, which is frequently presented as a location bias, does not necessarily preclude additionality.
To compare the benefits and drawbacks of traditional and automated conservation assessments, we used a field-based study and automated conservation assessments using GeoCAT, red and ConR to assess four species of Buddleja (Scrophulariaceae), a cosmopolitan genus of flowering plants. Buddleja colvilei, Buddleja sessilifolia, Buddleja delavayi and Buddleja yunnanensis are endemic to the Himalayan region. They have not yet been assessed for the IUCN Red List of Threatened Species but are facing elevated risks of extinction because of various anthropogenic and environmental pressures. Buddleja sessilifolia and B. delavayi are listed as Plant Species with Extremely Small Populations in Yunnan, China, where they are known to be threatened. Although automated assessments evaluated B. delavayi and B. yunnanensis as Endangered and B. sessilifolia and B. colvilei as Vulnerable, our field studies indicated a different categorization for three of the species: B. delavayi and B. yunnanensis as Critically Endangered and B. sessilifolia as Endangered. Our findings indicate that the accuracy and reliability of assessment methods can differ and that field surveys remain important for conservation assessments. We recommend an integrated approach addressing these limitations, to safeguard the future of other species endemic to the Himalayan region.
In West Africa, vast areas are being deforested; the remnant forest patches provide a wealth of ecosystem services and biodiversity conservation potential, yet they are threatened by human activity. Forest patches <100 ha have not been widely catalogued before; we mapped forest loss of small forest patches outside of protected areas in the Guinean savannah and humid Guineo-Congolian bioclimatic regions of Togo, Benin, Nigeria and Cameroon between 2000 and 2022. Focusing on the dynamics of small patches, without considering the splitting process of larger patches, we quantified changes in their number and area and the rate and trend of forest loss. Small forest patches are widespread, yet their area and number have decreased, while the forest loss rate is increasing. Primary forest patches lost almost half of their area annually – twice as much as secondary forests, and this loss was especially pronounced across small patches (0.5 – 10 ha), suggesting deforestation preferentially occurs in the smallest patches of primary forest. If forest loss continues at the current rate, 14% of the total forest area mapped in this study will have disappeared by 2032, jeopardizing their potential to provide ecosystem services and emphasizing the need for measures to counter their deforestation.
Understanding the relationships between cetaceans and their environment is crucial for conservation. This study examined humpback whales in Bahía de Banderas, Mexico, identifying key calving habitats. From 2018 to 2023, 1066 sightings were recorded, including 242 mother–calf groups, 109 mating groups, and 715 other groups. Spatial analysis revealed a non-random distribution; both the Kruskal–Wallis and Wilcoxon–Mann–Whitney tests detected significant differences (P < 0.05) in site preferences. Calving mothers favoured habitats with a mean depth of 59 m and a distance of 2 km from the coast, while mating groups preferred locations at 126 m and 4 km, and other groups chose areas at 149 m and 4 km. All groups were found in relatively flat areas around 2° seafloor slope. A dispersion test indicated a significant relationship between the location of calving mothers and environmental factors. K-means clustering showed 83.6% of calving mothers' sightings at depths less than 40 m and 2 km from the coast. Ensemble species distribution models identified three critical calving areas: one large area (261.8 km2) along the north coast and two smaller areas (9.5 and 5.4 km2) at the southern end of the bay. This study highlights Bahía de Banderas as a vital breeding habitat for humpback whales, providing insights for conservation strategies to protect calving grounds during the breeding season.
The hoary-throated spinetail and Rio Branco antbird are two bird species endemic to the Rio Branco drainage of Brazil and Guyana, currently listed as Critically Endangered on the IUCN Red List. Previous assessments of both species’ global populations focused on the Brazilian state of Roraima but did not include most of its border with Guyana, where significant areas of suitable habitat remain along the Ireng (Maú) and Takutu (Tacutu) Rivers. In July and August 2021, we conducted a survey to determine the extent of each species’ geographic range along the two rivers, and to estimate population sizes. We used playback surveys along 219 km of river to ascertain each species’ distribution and intensively sampled three forest blocks to determine densities. Both species were locally abundant on both sides of the international border. Rio Branco antbird occurred over a greater geographic range than hoary-throated spinetail, particularly along the Takutu River, but was confined to a narrower zone along the river edges. Both species appear to have retreated from habitat along the Ireng River that was occupied in the past, possibly due to habitat degradation from increasingly frequent fires. Nevertheless, our minimum estimates of 1147 antbirds and 851 spinetails in the study area represent, respectively, 7.5% and 17.8 % increases over current estimates of global population sizes, and indicate that the Guyana-Brazil border region may become a critical stronghold for both species if effective conservation measures are implemented. We propose establishment of a Key Biodiversity Area encompassing the core of both species’ distributions along the border; extensive follow-up work including stakeholder engagement to explore possibilities for habitat management and protection; and further field study to increase general ecological knowledge of these two bird species.
The Secretarybird Sagittarius serpentarius is a charismatic raptor of the grasslands and open savannas of Africa. Evidence of widespread declines across the continent has led to the assessment that the species is at risk of becoming extinct. Southern Africa was identified as a remaining stronghold for the species, but the status of this population requires reassessment. To determine the status of the species in South Africa, Lesotho, and Eswatini, we analysed data from a citizen science project, the Southern African Bird Atlas Project (SABAP). We implemented novel time-to-detection modelling, as well as summarisation of changes in reporting rates, using standard metrics, to determine the trajectory of the population. To cross-validate our findings, we used data from another citizen science project, the Coordinated Avifaunal Roadcounts (CAR) project. While our results were in agreement with previous studies that have reported significant declines when comparing SABAP1 (1987–1992) and SABAP2 (2007 and onwards), all analysis pathways that examined data within the SABAP2 period only, as well as CAR data from this period, failed to show an alarming declining trend over this more recent time period. We did, however, find some evidence for decreases in Secretarybird abundance in urban grid cells. We used random forest models to predict probability of occurrence, as well as probability of abundance (reporting rates) for the assessed region and provided population estimates based on these analysis pathways. Continued monitoring and conservation efforts are required to guard this population stronghold.
In Singapore, the Critically Endangered Sunda pangolin Manis javanica is threatened by habitat loss and fragmentation, and road traffic collisions. To mitigate these threats, an understanding of its spatiotemporal distribution is needed, as identified in the National Conservation Strategy and Action Plan for the species. However, Sunda pangolin occurrence data are held in multiple separate databases, are typically collected using non-standardized methods, and often lack accurate location details. To compile a complete georeferenced database of Sunda pangolin records in Singapore, we consolidated occurrence data from heterogeneous databases and mainstream and social media, and converted locality descriptions into geographical coordinates. We demonstrate the use of this database to analyse data on rescued pangolins and those killed on roads, to aid conservation efforts in Singapore, and describe other potential applications. We georeferenced 482 records of pangolin sightings, rescues and roadkill for 1996–2021, finding an increase in all three over the study period. Roadkill and rescues occurred mostly in central and western Singapore, close to forested areas, and were predominantly of subadults and adult males. The data can be used to inform threat mitigation strategies, post-rescue release plans and further research. The database has already been used in practice, contributing to environmental impact assessments and conservation recommendations. Overall, this georeferenced database demonstrates the value of citizen science and collating wildlife data from multiple sources, and the methods used can be applied to other taxa to aid conservation strategies.
In its nearly 80-year history, the International Whaling Commission (IWC) has shifted from a “whalers club” to an international governance body chiefly focused on the protection and conservation of global cetacean populations. Drawing on recent scholarship on extinction and its entanglements, this article compares two addresses given by whalers at IWC meetings 40 years apart to problematise the way whaling and its relation to extinction is conceptualised in international environmental governance. Guided by practice-oriented document analysis and recent theorisation of extinction as an entangled process, this article analyses the personal stakeholder testimonies from two different representatives of the North Slope whalers of Northern Alaska to the IWC – one in relation to the 1977 Alaska bowhead whaling controversy and the other in the context of the 2018 negotiations over streamlining Aboriginal Subsistence Whaling management and supporting greater flexibility and Indigenous autonomy. By comparing these two statements from very different points of history for the IWC and the governance of Indigenous whaling, this article illustrates some of the ongoing struggles for environmental governance to recognise extinction as a complex, multifaceted process that reverberates throughout human and more-than-human communities.
This article explores how time-related metaphors frame advanced cryopreservation technologies in environmental conservation. Cryopreservation “stops” or “freezes” biological time and “buys time” desperately needed to preserve species and ecosystems. We advance a framing of these technologies as logistical, highlighting how they create opportunities to shift materials, knowledge, and decision-making power through space and time. As logistical technologies, advanced cryopreservation techniques require active planning in the present rather than deferring responsibility and accountability to the future.
National Red Lists are useful tools in establishing local conservation priorities. The threat status of Estonian lichens based on the IUCN system has been assessed twice, in 2008 and 2023. In the latest Red List, the proportion of species of elevated conservation concern, that is taxa belonging to the Near Threatened and threatened categories or having become regionally extinct in Estonia, was high (58%) while Least Concern (LC) species represented one-third (36%) of all taxa. Macrolichens were more threatened than microlichens. The Red List Index (RLI), illustrating the trends of species in their projected extinction risk, was calculated. The values were low (< 0.7 in 2023), thus indicating a heightened risk both for the set of all species and for macrolichens. More than half of all Estonian lichens are associated with woodlands and 54% of these species are of elevated conservation concern. Lichens preferring broad-leaved deciduous trees included more threatened than LC species, while among lichens preferring other deciduous or coniferous trees the proportion of LC species was higher than that of threatened taxa. Lichens inhabiting calcareous grasslands had the highest share (69%) of taxa of elevated conservation concern. Comparisons of national red-listed data with four selected countries (Czech Republic, Denmark, Finland and Sweden) revealed that the biggest overlaps of Estonian taxa of elevated conservation concern were with the Czech Republic and Finland.
Anthropologist Richard Leakey sent Jane Goodall to Gombe (now Gombe Stream National Park) to study chimpanzees in the wild. As an anthropologist, he was keenly interested in human behavior, and believed that chimpanzees would provide a window to understanding it. It took Goodall six months of crawling around in the woods before any chimpanzees would allow her to get close enough to observe them. But her persistence paid off, as she was able to document chimpanzees showing some very human behavior including tool making, cooperative hunting and war making. Partway through her career, she elected to devote the rest of her career to environmental activism and education, and Gombe research was continued by a growing community of researchers including her student, Anne Pusey. Pusey was fascinated by mother–infant relationships, by developmental changes in juveniles as they matured, and by how chimpanzees manage to avoid breeding with close relatives. Other researchers at Gombe studied the relationship between rank and reproductive success, and how disease was influencing survival rates in three different populations in the region. Unfortunately, life table studies indicate that disease and a lack of immigrants into the region are threatening the viability of this iconic group of chimpanzees.
Plant names carry a significant amount of information without providing a lengthy description. This is an efficient shorthand for scientists and stakeholders to communicate about a plant, but only when the name is based on a common understanding. It is standard to think of each plant having just two names, a common name and a scientific name, yet both names can be a source of confusion. There are often many common names that refer to the same plant, or a single common name that refers to multiple different species, and some plants have no common name at all. Scientific names are based upon international standards; however, when the taxonomy is not agreed upon, two scientific names may be used to describe the same species. Weed scientists and practitioners can easily memorize multiple plant names and know that they refer to the same species, but when we consider global communication and far-reaching databases, it becomes very relevant to consider two sides of this shift: (1) a need for greater standardization (due to database management and risk of lost data from dropped cross-referencing); and (2) the loss of local heritage, which provides useful meaning through various common names. In addition, weed scientists can be resistant to changing names that they learned or frequently use. The developments in online databases and reclassification of plant taxonomy by phylogenetic relationships have changed the accessibility and role of the list of standardized plant names compiled by the Weed Science Society of America (WSSA). As part of an attempt to reconcile WSSA and USDA common names for weedy plants, the WSSA Standardized Plant Names Committee recently concluded an extensive review of the Composite List of Weeds common names and had small changes approved to about 10% of the list of more than 2,800 distinct species.