Data Deficient Research Articles

Cost-benefit analysis of acoustic recorders as a solution to sampling challenges experienced monitoring cryptic species.

The inferences that can be made from any study are limited by the quality of the sampling design. By bad luck, when monitoring species that are difficult to detect (cryptic), sampling designs become dictated by what is feasible rather than what is desired. We calibrated and conducted a cost‐benefit analysis of four acoustic recorder options that were being considered as potential solutions to several sampling restrictions experienced while monitoring the Australasian bittern, a cryptic wetland bird. Such sampling restrictions are commonly experienced while monitoring many different endangered species, particularly those that are cryptic. The recorder options included mono and stereo devices, with two sound file processing options (visual and audible analysis). Recording devices provided call‐count data similar to those collected by field observers but at a fraction of the cost, which meant that “idealistic” sampling regimes, previously thought to be too expensive, became feasible for bitterns. Our study is one of the few to assess the monetary value of recording devices in the context of data quality, allowing trade‐offs (and potential solutions) commonly experienced while monitoring cryptic endangered species to be shown and compared more clearly. The ability to overcome challenges of monitoring cryptic species in this way increases research possibilities for data deficient species and is applicable to any species with similar monitoring challenges.

Two new species of Primulina (Gesneriaceae) from limestone karsts of China.

The limestone karst area of South China is a major biodiversity hotspot of global terrestrial biomes. During extensive field work on the Guangxi limestone formations, two unknown species of Gesneriaceae were collected. After conducting a comprehensive study of the literature and herbarium specimens, Primulina davidioides and P. hiemalis are recognized as two species new to science, and described and illustrated here. P. davidioides is morphologically close to P. lunglinensis based on the shape of the leaf and flower, but it can be easily distinguished by the shape of the bracts, corolla and stigma, indumentum of peduncles, pedicels and pistil and number of staminodes. P. hiemalis is closely relate to P. luzhaiensis in vegetative appearance, but differs in the shape of the calyx and stigma, number of bracts and staminodes, indumentum of the leaf blade and peduncle, and position of stamens in the corolla tube. Considering that not enough is known about their populations, it is proposed that their conservation statuses should currently be classed as data deficient (DD) according to the IUCN Red List Category and Criteria.

What are We Conserving? A Case Study of Mentha longifolia and Allied Species from Lithuania

AbstractAssessment of the conservation status of a species, first, should be based on its clearly defined taxonomic identity. Insufficient knowledge of certain taxonomic groups may lead to misidentifications, misinterpretations and become an obstacle for conservation. Mentha longifolia, listed as a protected plant species of Lithuania since 1981, belongs to a taxonomically complex group of species. The aim of this research was to examine available herbarium specimens of M. longifolia and verify their identification, specify distribution of this species in Lithuania and evaluate its conservation status in the country. The study was based on the analysis of herbarium specimens and information provided in references and databases. We studied a total of 93 specimens initially identified as M. longifolia. Morphological features of 30 leaves (leaf length, leaf width, petiole length, distance from leaf base to the widest place, length of leaf tooth) of both M. longifolia and M. ×villosa were measured on herbarium specimens. After the revision of herbarium specimens, we revealed that 37.6% of specimens initially identified as M. longifolia belong to other species (mostly to M. ×villosa) and 29.0% of specimens cannot be identified precisely because of the early stage of development. Only 33.4% of M. longifolia specimens were identified precisely. Thus, M. longifolia, previously supposed as quite widespread in Lithuania, after the revision appeared to be restricted mainly to the southern and south-eastern parts of the country. Applying the IUCN criteria, M. longifolia was evaluated as data deficient (DD) species. Analysis of leaf morphological traits revealed that M. longifolia and M. ×villosa can be differentiated by the length and the width of leaf blade, the distance from leaf base to the widest part of leaf and by the ratio between the length and the width of middle cauline leaves. This study revealed that taxonomic revision of the genus Mentha in Lithuania is required. Distribution of species, ecology and state of populations, impact of alien species on native congeners should be estimated in the future.

Composition and structure of species along altitude gradient in Moghan-Sabalan rangelands, Iran

This study provides a checklist of species distributed at the altitude gradient of Moghan-Sabalan rangelands in Ardabili province, Northwest Iran. We evaluated the changes in species composition, growth types of species, Raunkiaer’s life forms, geographical distribution, threat and endemicity status, and palatability of species along two altitudinal gradients in the sampling plots, which were conducted in eleven sites/habitats with 300 meters above sea level (masl) altitude intervals (from 100 to 3300 masl). We assessed the plant species composition with special reference to the gradient analysis, and identified overall 396 species, which was comprising 44 families and 194 genera. Results showed that Asteraceae family is by far the most species-rich family, followed by Poaceae, Fabaceae, Caryophyllaceae and Brassicaceae. Among the genera, Astragalus is the most diverse genus, followed by Allium, Veronica and Bromus, Galium, Silene and Ranunculus. Results indicated that the number of species increased as the altitude increased to 1200–1500 masl, but then starts to decline to 3300 masl. Family-to-genera ratio was 1:4.4, the family-tospecies ratio was 1:9, and the genera-to-species ratio was 1:2.04. Growth type of species analysis shows that the frequency of perennial plants was higher in the study area followed by annual species while the lower group was biennial species. The number of annuals showed a decreasing trend towards higher altitude. Hemicryptophytes and therophytes were the most frequent life forms constituted each with (41.9%). Hemicryptophytes showed an increasing trend with altitude, while therophytes showed a decreasing trend with altitude increase, followed by geophytes, chamaephytes, and phanerophytes. Results showed more than half of the species of the study area belonged to Iran-Turanian region and these species showed an increasing trend with altitude. In contrast, Sahara-Sindian species comprise a minor component of the spectrum, with decreasing trend with altitude. The rare and endangered species out of the surveyed taxonomic groups comprised 53 species in total which 29 of them are considered lower risk (LR), 13 data deficient (DD), 5 vulnerable (Vu) and with 3 rare (R) and identified endemic plants comprised 24 species. Some 56.6% species were identified as class III, 22.6% were class I and 20.8% were class II as the palatability variation. Moghan-Sabalan rangelands require strong conservation management policies in case of species loss and changing natural communities due to the occurrence of conversion into cropland, over-grazing and other anthropogenic effects.

Evaluating the predicted extinction risk of living amphibian species with the fossil record.

Bridging the gap between the fossil record and conservation biology has recently become of great interest. The enormous number of documented extinctions across different taxa can provide insights into the extinction risk of living species. However, few studies have explored this connection. We used generalised boosted modelling to analyse the impact of several traits that are assumed to influence extinction risk on the stratigraphic duration of amphibian species in the fossil record. We used this fossil-calibrated model to predict the extinction risk for living species. We observed a high consensus between our predicted species durations and the current IUCN Red List status of living amphibian species. We also found that today's Data Deficient species are mainly predicted to experience short durations, hinting at their likely high threat status. Our study suggests that the fossil record can be a suitable tool for the evaluation of current taxa-specific Red Listing status.

Spatially explicit approach to estimation of total population abundance in field surveys

Population abundance is fundamental in ecology and conservation biology, and provides essential information for predicting population dynamics and implementing conservation actions. While a range of approaches have been proposed to estimate population abundance based on existing data, data deficiency is ubiquitous. When information is deficient, a population estimation will rely on labor intensive field surveys. Typically, time is one of the critical constraints in conservation, and management decisions must often be made quickly under a data deficient situation. Hence, it is important to acquire a theoretical justification for survey methods to meet a required estimation precision. There is no such theory available in a spatially explicit context, while spatial considerations are critical to any field survey. Here, we develop a spatially explicit theory for population estimation that allows us to examine the estimation precision under different survey designs and individual distribution patterns (e.g. random/clustered sampling and individual distribution). We demonstrate that clustered sampling decreases the estimation precision when individuals form clusters, while sampling designs do not affect the estimation accuracy when individuals are distributed randomly. Regardless of individual distribution, the estimation precision becomes higher with increasing total population abundance and the sampled fraction. These insights provide theoretical bases for efficient field survey designs in information deficiency situations.

Both cetaceans in the Brazilian Amazon show sustained, profound population declines over two decades.

Obligate river dolphins occur only in the rivers of Asia and South America, where they are increasingly subject to damaging pressures such as habitat degradation, food competition and entanglement in fishing gear as human populations expand. The Amazon basin hosts two, very different, dolphins—the boto or Amazon river dolphin (Inia geoffrensis) and the smaller tucuxi (Sotalia fluviatilis). Both species have wide geographical ranges and were once considered to be relatively abundant. Their IUCN Red List conservation status of Data Deficient (DD), due to limited information on threats, ecology, population numbers and trends, did not initially cause alarm. However, the development of dolphin hunting to provide fish bait at around the beginning of this millennium broadly coincided with the onset of a widespread perception that numbers of both species were in decline. Consequently, the need for population trend data to inform conservation advice and measures became urgent. This paper presents a 22-year time series of standardised surveys for both dolphins within the Mamirauá Reserve, Amazonas State, Brazil. Analysis of these data show that both species are in steep decline, with their populations halving every 10 years (botos) and 9 years (tucuxis) at current rates. These results are consistent with published, independent information on survival rates of botos in this area, which demonstrated a substantial drop in annual survival, commencing at around the year 2000. Mamirauá is a protected area, and is subject to fewer environmental pressures than elsewhere in the region, so there is no reason to suspect that the decline in dolphins within the Reserve is more pronounced than outside it. If South America's freshwater cetaceans are to avoid following their Asian counterparts on the path to a perilous conservation status, effective conservation measures are required immediately. Enforcement of existing fishery laws would greatly assist in achieving this.

Amphibians of the Reserva Ecológica Michelin: a high diversity site in the lowland Atlantic Forest of southern Bahia, Brazil.

An inventory of the amphibians of the Reserva Ecológica Michelin – REM in southern Bahia, Brazil is presented. Sixty-nine species were recorded during a ten-year sampling period. Amphibians were distributed in two orders (Gymnophiona and Anura), belonging to twelve families [Aromobatidae (1), Bufonidae (3), Centrolenidae (1), Craugastoridae (5), Eleutherodactylidae (3), Hemiphractidae (2), Hylidae (34), Phyllomedusidae (5) Leptodactylidae (7), Microhylidae (4), Odontophrynidae (3) and Caeciliidae (1)]. Fifty per cent of the reproductive modes known for Atlantic forest anurans were recorded. While no threatened species were found at REM, six species are classified as data deficient (DD) by the Brazilian Red List of threatened species and deserve additional attention. Phasmahyla timbo and Vitreorana eurygnatha are listed as endangered in Bahia according to the list of threatened species of the state. Despite a higher diversity of amphibians in the Atlantic forest having been reported for mountainous regions, our results revealed that amphibian richness for lowland forests is also high.

DNA barcoding of fishes from River Diphlu within Kaziranga National Park in northeast India

DNA barcoding technique has been gaining importance in biodiversity research for its easy and rapid ability of delineating organisms’ partial DNA sequences into molecular operational taxonomic units (MOTUs), and identification based on referral sequences from expert identified species. We generated mtCOI barcode sequences from morphologically identified fishes from River Diphlu in northeast India. A portion of this river falls within an important rhinoceros and tiger conservation site, the Kaziranga National Park. Partial mtCOI sequences for 103 fish specimens belonging to six orders, 19 families, 37 genera and 47 a priori identified species, were delineated into 48 MOTUs based on reciprocal monophyly criteria in maximum likelihood and Bayesian tree, and 49 groups by automatic barcode gap discovery (ABGD). Morphological and molecular basis of species identification was congruent for around 80% straightforward cases. We contributed barcodes for eight species which either had no barcodes in databases or are having ambiguous barcodes. We detected four ‘near threatened’ and two data deficient species as per the IUCN Red List status, besides a few ‘least concerned’ species. We also observed a wide scope of barcoding studies on fishes from northeast India to cover the endemic species and to resolve the prevailing taxonomic problems.

Gymnosperms on the EDGE

Driven by limited resources and a sense of urgency, the prioritization of species for conservation has been a persistent concern in conservation science. Gymnosperms (comprising ginkgo, conifers, cycads, and gnetophytes) are one of the most threatened groups of living organisms, with 40% of the species at high risk of extinction, about twice as many as the most recent estimates for all plants (i.e. 21.4%). This high proportion of species facing extinction highlights the urgent action required to secure their future through an objective prioritization approach. The Evolutionary Distinct and Globally Endangered (EDGE) method rapidly ranks species based on their evolutionary distinctiveness and the extinction risks they face. EDGE is applied to gymnosperms using a phylogenetic tree comprising DNA sequence data for 85% of gymnosperm species (923 out of 1090 species), to which the 167 missing species were added, and IUCN Red List assessments available for 92% of species. The effect of different extinction probability transformations and the handling of IUCN data deficient species on the resulting rankings is investigated. Although top entries in our ranking comprise species that were expected to score well (e.g. Wollemia nobilis, Ginkgo biloba), many were unexpected (e.g. Araucaria araucana). These results highlight the necessity of using approaches that integrate evolutionary information in conservation science.

Assessing the regional conservation status of sponges (Porifera): the case of the Aegean ecoregion

Sponges are among the less-studied benthic invertebrates as regards their extinction risk and conservation status. Herein, we evaluate the regional conservation status of sponges in the Aegean ecoregion (Eastern Mediterranean Sea), using the IUCN Red List criteria. We examined 20 sponge taxa falling into three categories: i) threatened species listed in Annex II of the Barcelona Convention, ii) bath sponge species (Annex III of the Barcelona Convention), and iii) Aegean endemics. The regional geographic range of the examined taxa was depicted on detailed distribution maps, based mostly on recent observations by the authors and literature data. When possible, population trends were estimated based on historical data, and threats were identified. The suggested regional conservation status of the examined sponge species is as follows: i) nine species were characterised as ‘Data Deficient (DD)’ due to limited available information; ii) seven species were assigned to the ‘Least Concern (LC)’ category; iii) the four harvested bath sponge species were assigned to the Endangered (EN) category, based on their population decline in the Aegean region during the past decades. The present evaluation, besides providing scientific data for the regional protection and management of sponge populations, can form a basis for wider assessment and consequent conservation of Porifera.

Human-modified landscape acts as refuge for mammals in Atlantic Forest

Abstract: Human-modified landscapes (HMLs) are composed by small, isolated and defaunated forest fragments, which are surrounded by agricultural and urban areas. Information on species that thrives in these HMLs is essential to direct conservation strategies in local and regional scales. Since HMLs are dominant in the Atlantic Forest, we aimed to assess the mammalian diversity in a HML in southeastern Brazil and to propose conservation strategies. We collected data of terrestrial (small-, medium- and large-sized) and volant mammals in three small forest fragments (10, 14 and 26 ha) and adjacent areas, between 2003 and 2016, using complementary methods: active search, camera trapping, live-traps, mist nets and occasional records (i.e., roadkills). In addition, we used secondary data to complement our species list. We recorded 35 native mammal species (6 small-sized, 16 medium- and large-sized, and 13 bats) and seven exotic species in the HML. The recorded mammal assemblage (non-volant and volant), although mainly composed of common and generalist species, includes three medium- and large-sized species nationally threatened (Leopardus guttulus, Puma concolor and Puma yagouaroundi) and two data deficient species (Galictis cuja and Histiotus velatus), highlighting the importance of this HML for the maintenance and conservation of mammal populations. Despite highly impacted by anthropogenic disturbances, the study area harbors a significant richness of medium- and large-sized mammals, being an important biodiversity refuge in the region. However, this biodiversity is threatened by the low quality of the habitats, roadkills and abundant populations of domestic cats and dogs. Therefore, we stress the need of conservation strategies focusing on the medium- and large-sized mammals as an umbrella group, which could benefit all biodiversity in the landscape. We recommend actions that promotes biological restoration, aiming to increase structural composition and connectivity of the forest fragments, reducing roadkills and controlling the domestic cats and dogs' populations, in order to maintain and improve the diversity of mammals in long-term.

A Study on the Ichthyofaunal Status of an Oxbow Lake of Eastern Himalayan River of Assam, India

The status of fish fauna of Kalpani beel in the Chirang district of Assam was studied from June to December, 2016. It is an ecologically important oxbow lake. The beel is fed by flood of Manas River originating from Bhutan and an important tributary of the river Brahmaputra. A total of 55 fish species belonging to 38 genera and 21 families (under 7 order) has been recorded during the study period from the lake. Out of these, 1.81% are endangered (EN), 3.63% are vulnerable (VU), 9.09% are near threatened (NT), 78.18% are least concern (LC), 1.81% are data deficient (DD) and 5.45% are not evaluated (NE). The highest no. of species is represented by cyprinidae family (22) followed by channidae (5), Bagridae (3), Mastacembelidae (3), osphronemidae (2), cobitidae (2), Ambassisdae (2), Nemacheilidae, Anabantidae, Badidae, Gobiidae, Nandidae, Notopteridae, Claridae, Heteropneustidae, Shilbeidae, Shilbeidae, Siluridae, Synbranchidae, Belonidae and Tetradontidae (1). The present paper deals with a list of ichthyofauna, collection locality, scientific name, local name based on their locality and their conservation status as per IUCN status. Keywords: Eastern Himalayan river, ichthyofaunal diversity, Kalpani beel, oxbow lake Cite this Article Jabin Chandra Ray, Jatin Sarmah. A Study on the Ichthyofaunal Status of an Oxbow Lake of Eastern Himalayan River of Assam, India. Research & Reviews: A Journal of Life Sciences. 2018; 8(1): 35–42p.

Aгарикоидные базидиомицеты зеленых насаждений города Петрозаводска (Республика Карелия)

The paper reports the results of studies on the taxonomic and trophic structure of agaricoid basidiomycetes in urban stands of the main forest tree species of the boreal zone (Betula, Larix, Picea, Pinus). Altogether 111 species of macromycetes of 59 genera, 33 families and 8 orders were found. The leader in terms of the number of species in this mycobiota is the group of mycorrhiza-forming fungi. The biota of agaricoid fungi is of the boreal type with the taxo-nomic structure most vividly demonstrating the traits of the mycobiota typical of the middle taiga subzone of Karelia. A distinctive feature of the mycobiota is the high number of species in the families Agaricaceae and Russulaceae, which are common in ruderal habitats and the forest zone. A comparison of the species composition and ratios in the taxonomic structure of the mycobiota between plant communities of urban and undisturbed areas, as well as Karelia in general showed a low level of similarity and pointed to gaps in the current inventory of agarics in the boreal zone of Republic. The highest species diversity of macromycetes was found in spruce stands, and the lowest in larch stands. The structure of the agaricoid fungal biota in sample plots in the spruce-, birch- and larch stands was relatively stable, with some fluctuation. As to the structure of the pine stand mycobiota, the spectrum of families ranked by the number of species in them changed along the human pressure gradient, and the trophic structure changed accordingly. The number of symbiotrophic species decreased, litter-related saprotrophs disappeared, the leading position was taken over by humus-related saprotrophs. The surveys revealed the presence of 11 red-listed species classified into two categories – near threatened (NT) and data deficient (DD) species.

Cyprinodontid fishes of the world: an updated list of taxonomy, distribution and conservation status (Teleostei: Cyprinodontoidea)

This checklist aims to list all the reported cyprinodontid fishes (superfamily Cyprinodontoidea/pupfishes) of the world. It lists 141 species in 8 genera and 4 families. The most diverse family is Cyprinodontidae (54 species, 38%), followed by Orestiidae (45 species, 32%), Aphaniidae (39 species, 28%), and Cubanichthyidae (3 species, 2%). Among 141 listed species, 73 (51.8%) species are Not Evaluated (NE), 15 (10.6%) Least Concern (LC), 9 (6.4%) Vulnerable (VU), 3 (2.1%) Data Deficient (DD), 11 (7.8%) Critically Endangered (CR), 4 (2.8%) Near Threatened (NT), 18 (12.8%) Endangered (EN), 3 (2.1%) Extinct in the Wild (EW) and 5 (3.5%) Extinct of the Red List of IUCN. They inhabit in the fresh, brackish and marine waters of the United States, Middle America, the West Indies, parts of northern South America, North Africa, the Mediterranean Anatolian region, coastal areas of the Persian Gulf and Makran Sea (Oman Sea), the northern Arabian Sea east to Gujarat in India, and some endorheic basins of Iran, Pakistan and the Arabian Peninsula.

An assessment of red list data for the Pezizomycotina (Ascomycota): Umbria (Italy) as a test case

A Red List of all 108 Pezizomycotina (Ascomycota) species recorded in Umbria Region (central Italy) is provided. According to the IUCN categories and criteria, 60.18% of the assessed species are classified as threatened, whereas 12.96% are Near Threatened (NT), 1.86% are Least Concerned (LC) and a noteworthy amount of 25% are Data Deficient (DD). As a consequence of the downlisting applied to the majority of the assessed taxa, according to the guidelines for application of IUCN red list criteria at Regional level, only 1.54% of the threatened species is Critically Endangered (CR), while 46.15% are Endangered (EN) and 52.31% are Vulnerable (VU). Given that the present work represents the first complete regional red list of Pezizomycotina in Italy, and that a national, as well as a European red list do not exist to date, it could be considered as a case study for other Italian Regions as well as for other European countries, aiming at the compilation of a national and European red list of this fungal group mostly overlooked in conservation strategies.

A Review of Recent Status on Stingrays (Chondrichthyes: Dasyatidae) In Indonesian Waters

TheIn this paper, the status of stingrays (family Dasyatidae) in Indonesian waters are summarized. There are 40 valid species of stingrays recorded here. Based on distribution of stingrays within seven faunal region of Indonesia, Kalimantan of Indonesian Borneo has 29 species, the largest diversity among other islands; following Sumatra (27 sepecies), Java (25 species), Sulawesi (14 species), Lesser Sundas (16), Mollucas (9 species) and Papua (17 species). According to the recent of Red List of Threatened Species of the International Union for the Conservation of Nature’s (IUCN 2017), there are 18 species are listed as threatened species (under Endangered and Vulnerable status), 2 as Near Threatened (NT), 3 as Data Deficient (DD), 5 s as Least Concern (LC) and 12 species are Not Evaluated (NE). Five species listed as Endangered should have high prioritize for conservation: Fluvitrygon oxyrhynchus (Sauvage, 1878); F. kittipongi (Vidthayanon & Roberts, 2005); F. signifer (Compagno & Roberts, 1982); P. solocirostris Last, Manjaji & Yearsley, 2005; and Urogymnus polylepis (Bleeker, 1852).

Why be red listed? Threatened Myriapoda species in Brazil with implications for their conservation.

The biodiversity crisis we live in, marked by high extinction rates, requires well-planned conservation efforts. To overcome this issue, red lists of threatened species are recognized as the main objective approach for evaluating the conservation status of species and therefore guiding conservation priorities. This work focuses on the Myriapoda (Chilopoda and Diplopoda) species listed in the Brazilian red list of fauna to enable discussion of the practical implications of red lists for conservation. Almost all myriapods assessed are endemic to Brazil (99 %) and 73 % are known from subterranean habitats only. Despite of 33 % being recorded from protected areas (PAs), downgrading, degazettement or downsizing of PAs and intense and unregulated ecotourism represent great threats. The PAs network in Brazil tends to fail in conserving myriapod species. The number of data deficient species (42 %) states the need of investing in ecological and taxonomic studies about the group, in order to fill in important knowledge gaps in species assessments nationally and globally. In this work we show that there is a lack of communication between national and global agencies concerning red lists, which results in a significant loss for science and for conservation. Despite investing in national and state red lists, individual countries must take the final step of submitting its data to IUCN global database, as significant international funding is available for IUCN red listed species conservation. Being one of the most diverse countries in the world, and facing the biggest cuts ever on national science funding, losing these important funding opportunities is a huge loss for Brazilian biodiversity conservation and for science. This study raises awareness on subterranean habitats conservation, due to its high endemism and fragility. Since the first edition of the Brazilian Red List in 1968, centipedes are now included for the first time, and millipedes for the second time. The presence of these myriapods in the list brings attention to the group, which usually receives little or no attention in conservation programs and environmental impact assessments. Rather than a specific case for Myriapoda and for Brazil, the points discussed here can be related to arthropods and the tropics, as the most biodiverse countries are emerging economies facing similar challenges in PAs network management, species extinction risks and science funding.

Gastrochilus dulongjiangensis (Aeridinae, Vandeae, Epidendroideae, Orchidaceae), a new species from Yunnan Province, China

Gastrochilus dulongjiangensis, a new species from Gaoligongshan National Natural Reserve, Yunnan, China, is described here. It is morphologically similar to G. pseudodistichus and G. fuscopunctatus, but can be distinguished from them by having the orbicular epichile, hypochile as wide as epichile and fusiform pollinia. A preliminary risk-of-extinction assessment shows that the new species should be regarded as Data Deficient (DD) according to the IUCN Red List Categories and Criteria.

Relating plant height to demographic rates and extinction vulnerability

To prioritize conservation efforts, it is important to know which plant species are most vulnerable to extinction. Intrinsic extinction vulnerabilities depend on demographic parameters, but for many species these demographic parameters are lacking. Body size has been successfully used as proxy of such parameters to estimate extinction vulnerability of birds and mammals. For plants, not all necessary demographic parameters have been related to size yet.Here, we derived allometric relationships with maximum plant height for the intrinsic population growth rate and the carrying capacity. Furthermore, for the first time, we derived a relationship between the variance in population growth rate due to environmental stochasticity and plant height. These relationships were used to relate extinction vulnerability to maximum plant height.Extinction vulnerability was found to be most sensitive to fluctuations in the population growth rate due to environmental stochasticity. Large plant species were less susceptible to environmental stochasticity, resulting in a lower vulnerability to extinction than small plant species. This negative relationship between plant size and extinction vulnerabilities is in contrast to previous results for mammals and birds.These results increase our theoretical understanding of the relationship between plant functional traits and extinction vulnerabilities and may aid in assessments of data deficient species. The uncertainty in the allometric relationships is, however, too large to quantify true extinction vulnerabilities. Further investigation in the relationship between demographic parameters and plant traits other than height is needed to further enhance our understanding of plant species extinction vulnerabilities.