The disparity between species description and conservation assessment: A case study in taxa with high rates of species discovery

Abstract

The IUCN Red List of Threatened Species (Red List) details the extinction risk of the world's species and presents an important biodiversity indicator for conservation policy. Its continued utility relies on it containing up-to-date information on the extinction risk of species. This requires both regular reassessments and the timely assessment of newly described species. We provide an overview of the status of amphibian Red List assessments to highlight the difficulties of keeping assessments updated for species groups with high rates of species description. Since the publication of the IUCN's Global Amphibian Assessment in 2004, description rates of new species and assessment rates were initially similar; yet while the former has remained consistent, the latter has recently sharply declined. Currently 61.3% of amphibian species are either Not Evaluated or have out-of-date assessments. The situation is particularly problematic in countries with the richest amphibian diversity, which typically have the highest rates of amphibian species discovery and face the greatest threats. Efforts to keep the Red List up-to-date are primarily limited by funding, we estimate that an annual investment of US $170,478−$319,290 is needed to have an up-todate Red List for amphibians. We propose suggestions to increase assessment rates by improving the availability of data relevant to the process: authors of species descriptions or taxonomic revisions should publish information relevant to Red List assessments. Taxonomic journals should suggest inclusion of such information in their author guidelines. We suggest that contributors with significant input into assessments should be rewarded with co-authorship of published assessments. Keywords Amphibian, conservation prioritization, Global Amphibian Assessment, IUCN Red List of Threatened Species, extinction risk. Introduction The IUCN Red List of Threatened Species (hereafter the 'Red List') is a centralised, widely accepted measure of global extinction risk used to identify threats and priority conservation actions (Lamoreux et al. 2003; Rondinini et al. 2014). The Red List tracks changes in extinction risk over time, and is important in measuring threats to biodiversity and evaluating the impact of conservation intervention on a global scale (Hoffmann et al. 2010). The Red List has significant influence over which research and conservation work is resourced as grant funding often prioritizes globally threatened species. It also underpins the Red List Index, an important biodiversity indicator steering conservation policy (Butchart et al. 2004; Butchart et al. 2007; Butchart et al. 2010). The Red List is currently supported by fund-raising efforts carried out by the IUCN and Red List Partners, and through philanthropy (Rondinini et al. 2014; Juffe-Bignoli et al. 2016). However, once a taxonomic group has been comprehensively assessed, funding for subsequent assessments is not readily available (Rondinini et al. 2014). Much of the work required to assess a species, particularly provid...

Historical museum collections clarify the evolutionary history of cryptic species radiation in the world's largest amphibians

“…The conservation of highly threatened taxa is dependent upon the availability of robust baseline information on key population parameters (Segan, Bottrill, Baxter, & Possingham, 2011;Sutherland, Pullin, Dolman, & Knight, 2004). Most fundamentally, determining species boundaries and understanding the taxonomic identity and distinctiveness of populations of conservation concern are essential steps needed to define appropriate management units and inform effective management decisions (Mace, 2004;May, 1990;Tapley et al, 2018). However, many recent examples exist of conservation efforts being delayed or misdirected due to inaccurate taxonomic assessment, in some cases resulting in catastrophic decline or even extinction of evolutionarily significant populations and distinct species (e.g., Beebee et al, 2005;Iglésias, Toulhoat, & Sellos, 2010;Robertson, Stephenson, & Goldstien, 2011).…”

Assessment gaps and biases in knowledge of conservation status of fishes

“…Certain fish orders are better assessed, such as sharks and rays (Dulvy et al, 2014), while others lack sufficient assessment (Scorpaeniformes, Gymnotiformes). Species assessed had been described earlier than unassessed ones, resulting in an assessment gap for fish species described during the most recent decades, comparable with a similar gap observed in reptiles (Meiri & Chapple, 2016) and amphibians (Tapley et al, 2018). No evidence was found to support the hypothesis that assessment rates are higher in species with higher commercial interest or value.…”

“…Furthermore, comparing data from fish with other vertebrate groups, fish species have been suffering from an evaluation decline since the 1980s which, combined with an increase in species discovery, results in a large proportion of recently discovered species not being evaluated, a trend shared with reptiles (Meiri, ) and amphibians (Tapley et al, ). In the case of amphibians, for which previously complete global assessments had been carried out, assessments are now rapidly becoming outdated with an increasing proportion of non‐evaluated species (Tapley et al, ).…”

“…Furthermore, comparing data from fish with other vertebrate groups, fish species have been suffering from an evaluation decline since the 1980s which, combined with an increase in species discovery, results in a large proportion of recently discovered species not being evaluated, a trend shared with reptiles (Meiri, ) and amphibians (Tapley et al, ). In the case of amphibians, for which previously complete global assessments had been carried out, assessments are now rapidly becoming outdated with an increasing proportion of non‐evaluated species (Tapley et al, ). Previous studies with lizards and snakes (Böhm et al, ; Meiri & Chapple, ) have found that those species easier to study (with large range sizes, or in temperate latitudes) are described earlier and are better assessed, whereas species with small ranges and inhabiting tropical regions remain unassessed or even undiscovered, with higher risk of extinction as a result of their rarity (Pimm et al, ).…”

“…amphibians (Tapley et al, 2018). In the case of amphibians, for which previously complete global assessments had been carried out, assessments are now rapidly becoming outdated with an increasing proportion of non-evaluated species (Tapley et al, 2018).…”