IUCN Threat Categories Research Articles

The state of the bats in North America.

The world's rich diversity of bats supports healthy ecosystems and important ecosystem services. Maintaining healthy biological systems requires prompt identification of threats to biodiversity and immediate action to protect species, which for wide-ranging bat species that span geopolitical boundaries warrants international coordination. Anthropogenic forces drive the threats to bats throughout North America and the world. We conducted an international expert elicitation to assess the status of 153 bat species in Canada, the United States, and Mexico. We used expert assessment to determine the conservation status, highest impact threats, and recent population trends for these species. We found that 53% of North American bat species have moderate to very high risk of extinction in the next 15 years. The highest impact threats varied with species and country, and four IUCN threat categories had the greatest overall impacts: Climate Change, Problematic Species (including disease), Agriculture, and Energy Production. Experts estimated that 90% of species assessed had decreasing population trends over the past 15 years, demonstrating the need for conservation action. Although the state of North American bats is concerning, we identify threats that can be addressed through internationally collaborative, proactive, and protective actions to support the recovery and resilience of North American bat species.

Toward the first Red List of Latvian lichens according to the IUCN criteria

Lichens are well-known bioindicators and exhibit high sensitivity to environmental changes due to their unique biological characteristics. Despite their ecological significance, lichens are often overlooked in conservation policies both at the European Union (EU) and global levels. The situation is better at the level of national Red Lists that can provide candidate species for regional or global Red Lists, thereby helping to prioritize conservation efforts. To fill a gap at the national level, this article presents the comprehensive data of the Red List of Latvian lichens. For the first time, IUCN threat categories and criteria were applied to assess 85 lichenized and one lichenicolous fungus during 2022–2023. Of these species, 3 were classified as Least Concern (LC), 2 as Data Deficient (DD), 11 as Near Threatened (NT), and 68 were ascribed the threatened categories: 14 to Vulnerable (VU), 27 to Endangered (EN), 27 to Critically Endangered (CR). The majority of Latvian lichens categorized as threatened or near threatened inhabit woodlands, particularly old-growth forests, which face the primary threat of intensive forest management. This article emphasizes the importance of continued evaluation efforts, while also addressing challenges associated with data scarcity and limited lichenological research capacity in Latvia.

On the macroecology of rarity and vulnerability to extinction in terrestrial mammals

Understanding the interplay between rarity and vulnerability in the decline and extinction of species is a major challenge for modern conservation biology. In addition to traditional approaches, answering this question necessarily requires integrating new methodologies and information on species' life-history traits and responses to environmental stressors. Here we use data for over 4000 mammal species to: (1) assess which forms and levels of rarity are most represented across current IUCN threat categories; (2) test whether interspecific variation in vulnerability is more closely linked to intrinsic traits related to their rarity, or to extrinsic factors related to anthropogenic pressures; and (3) identify geographical areas where species with high potential vulnerability are particularly common and assess their overlap with forecasts of land cover change. To achieve these goals, we model the directional influence of life-history traits related with rarity and extrinsic correlates on vulnerability. Our results confirm the strong link between rarity and vulnerability within mammalian orders. A model encompassing the three main rarity traits (i.e. range size, population density, and habitat breadth) correlates with vulnerability, despite not being directly correlated with population density. Recent habitat changes (within the past 35 years) did not show a direct relationship with vulnerability, but the contractions in range size reveal a more complex long-term effect on species vulnerability. Given the current scenario of limited conservation resources, we anticipate that knowledge about the characteristics most associated with vulnerability, coupled with mapping species possessing these traits and facing potential future land changes, can facilitate the development of more precise and effective conservation strategies aimed at preventing species extinctions.

Reclassifying the Threat Categories of Two Rare Plant Species Endemic to Central Anatolia

Aethionema turcica and Astragalus beypazaricus are rare endemic plant species restricted to marly-gypsaceous soils from Ankara, Turkey. In a study in 2000, Ae.turcica and A.beypazaricus were classified under the “Least Concern” and “Critically Endangered” threat categories, respectively. This study aimed to reassess the global conservation status of these species according to the IUCN Red List Categories and Criteria by using the recent findings based on their population sizes, distribution areas, and the main threats. Field research was conducted between 2016 and 2018. Additionally, physical-chemical soil tests were run, and the climatic data were utilized to draw bioclimatic conclusions. In Ankara, there are two populations of Ae.turcica, with 359 mature individuals covering 12 km2 AOO and 23.5 km2 EOO areas. A.beypazaricus has only one fragmented population with a total of 5700 mature individuals in Beypazarı, and both AOO and EOO were discovered to be 4 km2. Both species are on the verge of extinction due to habitat fragmentation and loss formed by intense anthropogenic activity. According to the findings, the IUCN threat categories for Ae.turcica and A.beypazaricus were suggested to be reclassified as CR based on the criteria B1ab(ii, iii) and B1ab(ii, iii)+2ab(ii, iii), respectively.

Hedysarum vuralii (Fabaceae), a new species from Turkey

Hedysarum vuralii, a new species in the tribe Hedysareae (Fabaceae), is described and illustrated. It belongs to Hedysarum section Multicaulia, collected from Ankara province in Turkey. H. vuralii is closely related to H. dededaghense but differs in densely adpressed white sericeous stem indumentum (versus spreading pilose); 7–10 paired, narrower, and glabrous above leaflets (5–16 ×1–3 mm, versus 7–8 paired, oblong-elliptic, 5–20 × 2–5 mm, spreading hairy on both surface); longer bracteoles (5–6 mm long, versus 3–4 mm); calyx teeth at least twice as long as tube (versus as long as tube); corolla greenish yellow, violet spotted at tips (versus purple); shorter standard (15–16 mm long, versus 19 mm); pods 12 × 4 mm, 2 (–3)-jointed (versus 14 × 5–6 mm, 1–2 jointed); joints 4–6 × 2–4 mm, pubescent with echinate in the center (versus c. 6 ×6, pubescent with setae). Taxonomic descriptions, images, the identification key, phenology, palynology, and the IUCN threat category of the new species were presented. Moreover, the geographical distribution of H. vuralii and H. dededaghense were mapped.

A New Rupicolous Species from West of Türkiye: Stachys cuhacioglui (Lamiaceae)

Stachys is one of the most diverse genera of the family Lamiaceae and currently consists of 360 species. Here, we describe Stachys cuhacioglui (Lamiaceae) as a new species based on morphological and micromorphological data. The new species was discovered in İzmir province in west of Türkiye. Stachys cuhacioglui differs from S. annua complex by its perennial, chasmophyte habitus, cordate basal leaves, shorter campanulate calyx with recurved teeth, and shorter corolla. The description, etymology, phenology, geographical distribution, IUCN threat category and ecology of the new species are given.

Can an acoustic observatory contribute to the conservation of threatened species?

AbstractObservatories are designed to collect data for a range of uses. The Australian Acoustic Observatory (A2O) was established to collect environmental sound, including audible species calls, from 344 recorders at 86 sites around Australia. We examine the potential of the A2O to monitor near threatened, threatened, endangered and critically endangered species, based on their vocal behaviour, geographic distributions in relation to the sites of the A2O and on some knowledge of habitat use. Using IUCN and EPBC lists of threatened and endangered species, we extracted species that vocalized in the audible range, and using conservative estimates of their geographic ranges, determined whether there was a possibility of hearing them at these sites. We found that it may be possible to detect up to 171 threatened species at sites established for the A2O, and that individual sites have the potential to detect up to 40 threatened species. All 86 sites occurred in locations where threatened species could possibly be detected, and the list of detectable species included birds, amphibians, and mammals. We have incidentally detected one mammal and four bird species in the data during other work. Threatening processes to which potentially detectable species were exposed included all but two IUCN threat categories. We concluded that with applications of technology to search the audio data from the A2O, it could serve as an important tool for monitoring threatened species.

Vertebrate cave fauna troglobite and troglophile of the karst system of La Paz, in the Andean Region of Colombia, with notes on local extinction record

La Paz is a municipality located in the Eastern Andes of Colombia and has a great variety of hipogean and epigean karstic environments. Different speleological explorations carried out in the last decades in La Paz region have reported the existence of at least 23 subterranean environments including caves, caverns, grottos, holes, and sinkholes, of which the most remarkable due to its vertical depth is the Hoyo del Aire, a Sima-type geological formation with a vertical drop greater than 140 m and a diameter of 130 m. The presence of troglobite and troglophile vertebrate fauna was rereported, in only 17 of the 23 hypogean environments explored. The locations were visited in 2017 and 2019 and the existence of seven genera and 10 species including birds, bats, and fish were recorded, and of these, two species being endemic with their distribution restricted to the department of Santander. Additional data on the species analyzed including origin, common name, geographic distribution, and conservation status following IUCN threat categories are presented. Finally, the local extinction of a bird population extirpated from the Hoyo del Aire subterranean habitat is reported. The authors suggest that the national and municipal environmental authorities recognize the karstic area of La Paz as an area of environmental interest for conservation and regulated tourist use.

Anthropogenic Threats to Alligator Snapping Turtles (Chelydridae: Macrochelys)

With the conservation status of Macrochelys (alligator snapping turtles) being examined at the national level, our objective was to compile categorical data on threats from anthropogenic interactions. We included information from (1) author-collected anecdotes on human–turtle interactions and (2) radiographs to assess the prevalence of ingested fishing hooks. We placed 173 interactions involving 192 incidents into 9 IUCN threat categories and found bycatch involving fish hooks to be 4 times more numerous than the second-most numerous threat, turtle persecution. Fishing bycatch resulted in a high proportion of turtle mortalities (39%), and bycatch incidents in several cases preceded the highest-mortality threat (53%), persecution of individuals involving shooting or blunt trauma. We recommend fishing bycatch-mitigation measures and educational efforts to help conserve Macrochelys.

Long-term data show alarming decline of majority of fish species in a Lower Mekong basin fishery

Overexploitation, habitat fragmentation, and flow alteration are major threats to freshwater biodiversity that can lead to fisheries collapse and species extinction. These threats are particularly alarming in poorly monitored ecosystems where resource use supports the livelihoods of numerous people. The Tonle Sap Lake in Cambodia is such an ecosystem, supporting one of the world's largest freshwater fisheries. Tonle Sap Lake fishes are the focus of indiscriminate harvest affecting species stocks, community composition and food-web structure. Changes in the magnitude and timing of the seasonal flood pulse have also been linked to declines in fish stocks. Yet, changes in fish abundance and species-specific temporal trends remain poorly documented. Analyzing 17 years' time series of fish catch data for 110 species, we show that fish populations have declined by 87.7 %, owing to a statistically significant decline for >74 % species, particularly the largest ones. Despite large variations in species-specific trends - going from locally extinct to >1000 % increase - declines were found across most migratory behaviors, trophic positions or IUCN threat categories, though uncertainty regarding the magnitude of effect precluded us drawing conclusions in some cases. These results, reminiscent of alarming declines in fish stocks in many marine fisheries, provide unequivocal evidence that Tonle Sap fish stocks are increasingly depleted. The consequences of this depletion on ecosystem function are unknown but will undoubtedly affect the livelihoods of millions of people, stressing the need to set-up management strategies aimed to protect both the fishery and its associated diversity. Flow alteration, habitat degradation / fragmentation - especially deforestation of seasonally inundated areas and overharvest - have been reported as major drivers in population dynamics and community structure, highlighting the need for management efforts aimed at preserving the natural flood pulse, protecting flooded forest habitats, and reducing overfishing.

An annotated checklist of flora of Overa-Aru wildlife sanctuary, Kashmir Himalaya

The Overa-Aru wildlife sanctuary is one of the largest protected areas in terms of area (425 km2) in Kashmir Himalaya. Here, we present an annotated checklist of flora of the sanctuary, which includes 397 taxa (392 species, 1 subspecies, 3 varieties and 1 forma) belonging to 254 genera in 76 families. Asteraceae was the dominant family with 57 species, followed by Rosaceae and Lamiaceae with 28 and 27 species respectively. Likewise, Salix and Veronica were the dominant genera with 7 species each, followed by Artemisia with 6 species. The herbs were dominant (307 species, 77.33%) followed by trees (41, 10.33%). Lifespan wise, perennials were dominant (318 species, 80.1%), followed by annuals (66, 16.62%). The hemicryptophytes were the dominant life forms (224 species, 56.42%), followed by phanerophytes (80, 20.15%). Further, nine species occurring in sanctuary are currently recognized under different IUCN threat categories. The checklist provides the first-ever comprehensive documentation of the flora from this Kashmir Himalayan protected area, supplemented with details on natural life-history traits and up-to-date conservation status. Hopefully, the study will be immensely useful in guiding suitable conservation strategies and management planning of protected areas in the region.

Taxonomy and distribution of Taraxacum sect. Erythrosperma (Asteraceae) in Poland.

The dandelions from Taraxacumsect.Erythrosperma are taxonomically well distinguished and ecologically restricted to warm and sunlit habitats of steppes, dry and sandy grasslands, and distributed in temperate regions of Europe and Central Asia, with some being introduced to North America. Despite the long tradition of botanical research, the taxonomy and distribution of dandelions of T.sect.Erythrosperma is still underexplored in central Europe. In this paper, by combining traditional taxonomic studies supported by micromorphological, molecular and flow cytometry analyses as well as potential distribution modelling we shed light on taxonomical and phylogenetical relationships between members of T.sect.Erythrosperma in Poland. We also provide an identification key, species-checklist, detailed descriptions of morphology and occupated habitats as well as distribution maps for 14 Polish erythrosperms (T.bellicum, T.brachyglossum, T.cristatum, T.danubium, T.disseminatum, T.dissimile, T.lacistophyllum, T.parnassicum, T.plumbeum, T.proximum, T.sandomiriense, T.scanicum, T.tenuilobum, T.tortilobum). Finally, conservation assessments performed using the IUCN method and threat categories for all the examined species are proposed.

Prioritizing Conservation and Research Effort for Poorly Known Species: The Buttonquails (Turnicidae) as a Study Case

Conservation status assessment of bird species is essential to prioritize conservation and monitoring efforts; however, this is not always possible to achieve due to lack of field data or scientific knowledge. In this context citizen science platforms can act as a data source to prioritize the conservation and research resources within a region or a given taxonomic group. Merging the available information on bird distribution areas from BirdLife International and field observations from eBird, the main citizen science birding app, we create a concern index, using the poorly known buttonquails (Turnicidae) as a case study. This concern index is based on two parameters: scarcity and uncertainty, which ultimately are based on two components, respectively. For every species, we defined scarcity as a combination of its frequency of occurrence (proportion of positive eBird checklists) and its relative range size, while uncertainty is a combination of the eBird effort (density of eBird checklists) and the range accuracy (proportion of positive eBird checklists within the BirdLife distribution area). We found a high correlation (Spearman r = 0.74) between our concern index and the IUCN threat categories for all buttonquail species. Then we apply this concern index to all buttonquail subspecies obtaining a ranked list for these non-assessed taxa, with some island endemic subspecies ranking very high together with the most endangered buttonquail species. Our approach is a very simple method to rank species within a given bird group and prioritize monitoring and conservation efforts. Moreover, it is also suitable for other taxonomic levels as subspecies or even for ecological units as populations, which normally lack a formal conservation status assessment.

Effects of Anthropogenic Habitat Fragmentation on the Genetic Connectivity of the Threatened and Endemic Campylorhynchus yucatanicus (Aves, Trogloditydae) in the Yucatan Peninsula, Mexico

Identifying connectivity patterns among remnant bird populations and their relationships with land use practices and adjacent habitat fragments is key to implementing appropriate long-term management strategies for species conservation. The coastal scrub and dune vegetation complex of the northern Yucatan Peninsula is rich in endemisms and has been affected by human development, which threatens the survival of the Yucatan Wren (Campylorhynchus yucatanicus) population, an endemic bird species. To identify possible anthropogenic barriers to the connectivity of C. yucatanicus along 14 localities in the Yucatan (Mexico) coastal north, we explored the relationship between the species population’s genetic variability at each sampled site and landscape structure using regression models, in addition to the relationship between genetic distance and landscape resistance. Seven nuclear microsatellite loci were used as genetic markers. Four genetic populations were highlighted by the clustering method implemented in the Geneland program. Human settlement and availability of adequate habitat were significantly related to genetic distance (Fst), suggesting limited connectivity among sites due to ongoing land use changes. We suggest changing the IUCN threat category of C. yucatanicus to endangered as we found a significant loss of genetic variability in addition to restricted distribution, small population, habitat degradation, and loss of connectivity.

A new Hedysarum L. species (Fabaceae) from Türkiye, Hedysarum dazkiriense

A new species, Hedysarum dazkiriense, in the genus Hedysarum (Fabaceae) was described and illustrated here and is only known from Dazkırı district in Afyonkarahisar Province in Türkiye. The species belongs to sect. Multicaulia and it is closely related to H. syriacum, but it is distinguished from it by having 5–8 pairs and smaller leaflets (3–7 × 1–2 mm, not 4–6 pairs and 15–22 × 5–12 mm); calyx 2–3 mm long (not 8–9 mm), standard 14–16 mm long (not 18–22 (–24) mm). Also, it is similar to H. pestalozzae, but distinctly different from it by having smaller leaflets (3–7 × 1–2 mm, not 5–14 × 2.5–4 mm), smaller calyx (2–3 mm long not 4–6 mm), lomentum sparsely hirsute and without setae (not densely tomentose, with or without setae). Taxonomic descriptions, images, the identification key, phenology, palinology and the IUCN threat category of the new species were presented. In addition, the geographical distribution of H. dazkiriense, H. syriacum and H. pestalozzae were mapped.

Türkiye’deki Kyllinga Rottb. (Cyperaceae) cinsinin koruma statüsü, mikro ve makro morfolojisi

The macro and micro morphology of Kyllinga brevifolia, an invasive species, was investigated in this study. K. brevifolia species has been thoroughly described, and population distribution data has been updated. Furthermore, the populations of K. brevifolia species in our country were assessed, and the IUCN threat category was identified. Kyllinga brevifolia pollen grains are spherical in shape and have a micro-echinate-perforated surface ornamentation. The fruit of K. brevifolia is obovoid and elliptical in shape, with a lenticular cross section, and the fruit surface ornemantation is reticulated-tuberculate. The most important aspect of combating invasive species is understanding the plant well enough to combat it. In our study, the characteristics of an invasive species, K. brevifolia, are described in detail. Furthermore, this study determined the pollen and fruit morphology of K. brevifolia for the first time.

Thirty-two new and noteworthy floristic records from north-eastern Greece.

BackgroundThe vascular flora of Greece comprises no less than 6,705 vascular plant taxa (species and subspecies, including established aliens) in an area of 131,957 km2. The phytogeographic region of north-east Greece (NE), an area characterised by physiographic diversity, is the richest floristic region in Greece, yet it remains less-explored compared to other regions.New informationWe present an annotated inventory of 32 vascular plant taxa collected predominantly from the East Macedonia and Thrace Regions (Makedonia and Thraki, NE Greece), following fieldwork that took place between 2013 and 2021. In our results, we identify seven new additions to the Greek flora (Aethionemasaxatilesubsp.rhodopaeum, Anthericumramosum, Asteramellus, Euphorbiacarniolica, Hesperismatronalissubsp.matronalis, Saponariastranjensis and Silenefetlerii) and 25 new records to the regional Greek flora consisting of mostly rare Balkan endemics of a restricted distribution and presumable conservation priorities. Taxonomic comments are added, where necessary. IUCN threat categories are assigned to certain taxa. Our investigation highlights the importance of the Balkan border areas as a source of new floristic elements for single countries and points to the importance of range-restricted taxa, in addition to single-country endemics, to address plants with a narrow distribution pattern.

A new subspecies of Stachys cretica (Lamiaceae) from western Turkey

A new subspecies of Stachys cretica (Lamiaceae) from Turkey, Stachys cretica subsp. gulendamiana, is described and its relationships with allied subspecies is discussed. The new subspecies is characterized by having decumbent flowering stems. Stachys cretica subsp. gulendamiana is similar to S. cretica subsp. anatolica, but it differs mainly by its marine sandy habitat, indumentum adpressed white lanate—tomentose, flowering stems decumbent, basal leaves undulate, nutlets dull, greyish—brown. IUCN threat category, geographical distribution map and ecology of the new subspecies are also given.

Rhanteriopsis baskilensis sp. nov. (Inuleae, Asteraceae), a new species from Turkey

Some interesting Asteraceae specimens were collected from Baskil (Elazığ, Turkey) with palea on its receptaculum, few and flat pappus bristles. After our examination, it was understood that the specimens belonged to Rhanteriopsis, which is a new genus record for Turkey. The specimens are morphologically similar to R. microcephala, which is endemic to Syria, and R. puberula, which is distributed in Iraq and Iran. However, the Turkish specimens differ from these species in its involucral bracts and paleae being narrower, achenes shorter, and pappus bristles 5. In this study, a detailed description of the new species, its morphological comparison with R. microcephala and R. puberula, photographs and some ecological information are given. In addition, an IUCN threat category is proposed for the new species, taking into account the existing and potential threats to its distribution.

Ranking the direct threats to biodiversity in sub-Saharan Africa

Sub-Saharan Africa receives large investments in biodiversity conservation, and if these investments can be concentrated on the highest threats to biodiversity, the benefits to conservation from the investments would increase. Yet there is no available prioritization of the many direct threats to biodiversity to inform organizations developing sub-Saharan or sub-regional conservation strategies. Consequently, regional investments by funders of biodiversity conservation such as international conservation organizations, foundations, and bilateral and multilateral donors may be suboptimal. The objective of this study was to determine what are the highest direct threats to biodiversity in sub-Saharan Africa and its sub-regions. To do this, we collected threat data using standardized IUCN threat categories from a Delphi consensus of sub-Saharan Africa biodiversity experts, known threats to IUCN Red-listed sub-Saharan African species, and National Biodiversity Strategy and Action Plans from 40 sub-Saharan African countries. After averaging the threat ranking from the three sources, the highest threats were: (1) annual and perennial crops (non-timber); (2) fishing and harvesting aquatic resources in marine and freshwater areas; (3) logging and wood harvesting in natural forests; and (4) hunting and collecting terrestrial animals. The highest-ranked sub-regional threats were hunting in Central Africa and agriculture in East Africa, Southern Africa, and West Africa. Aligning biodiversity investments to address these threats and tailoring activities to reflect local socio-ecological contexts would increase the conservation of biodiversity in sub-Saharan Africa.