Comparing and contrasting threat assessments of plant species at the global and sub-global level

Abstract

Evidence-based assessments of extinction risk are established tools used to inform the conservation of plant species, and form the basis of key targets within the framework of the Global Strategy for Plant Conservation (GSPC). An overall picture of plants threat assessments is challenging due to the use of a variety of methodologies and range in scope from global to subnational. In this study, we quantify the state of progress in assessing the extinction risk of all land plants, determine the key geographic and taxonomic gaps with respect to our understanding of plant extinction risk, and evaluate the impact of different sources and methodologies on the utility of plant assessments. To this end, we have analyzed a cleaned dataset compiled from IUCN Red List of Threatened Species and Regional Red Lists. We reveal that there are assessments available for 89,810 distinct species or 25% of all accepted land plant species. However unlike with other major organismal lineages the bulk of the plant species assessments are derived from Regional Red Lists, and not the Global IUCN Red List. We demonstrate that this bias towards regional assessments results in distinct taxonomic and geographic strengths and weaknesses, and we identify substantial taxonomic and geographic gaps in the assessment coverage. With species that have been assessed in common at both global and regional levels, we explore the implications of combining threat assessments from different sources. We find that half of global and regional assessments do not agree on the exact category of extinction risk for a species. Regional assessments assign a higher risk of extinction; or underestimate extinction risk with almost equal frequency. We conclude with recommended interventions, but support the suggestion that all threat assessments should be pooled to provide more data and broaden the scope of threat assessments for monitoring progress towards GSPC targets.

The macroecology and macroevolution of plant species at risk

“…The Sampled Red List indicates that c. 20% of extant plants are currently threatened globally, similar to the proportion observed in mammals, more threatened than birds, but less threatened than amphibians (Brummitt et al, 2015). The incomplete sampling of the formal plant Red List may, however, introduce further biases that mislead our understanding of extinction risks (Mounce et al, 2018). For example, a geographical bias in completeness of Red List assessments that favours more-developed countries may overlook the importance of extinction drivers in developing countries and fail to identify the key species traits that determine species sensitivities to these drivers.…”

Automated conservation assessment of the orchid family using deep learning

“…1). This approach is particularly valuable for the species-rich, but data-poor, tropical regions of Earth (Mounce et al 2018), where even preliminary assessments will be useful for informing conservation. A particular strength of IUC-NN is that it can be trained for other taxonomic groups or regions contributing to speeding up the conservation assessment of all species on Earth.…”

How to hierarchise species to determine priorities for conservation action? A critical analysis

“…2 The different hierarchisation methods for species can have different objectives (in grey: focus of this study) conservation priority, though being linked, are different concepts (IUCN 2012). Moreover, extinction risk assessment could be different according to the method used (Mounce et al 2017). However, red lists are often mistakenly considered as hierarchical lists of priorities for conservation actions, and thus conservation priorities are mainly or only based on this assessment of extinction risk (Miller et al 2006).…”