title: Toward reassessing data-deficient species.
abstract: One in 6 species (13,465 species) on the International Union for Conservation of Nature (IUCN) Red List is classified as data deficient due to lack of information on their taxonomy, population status, or impact of threats. Despite the chance that many are at high risk of extinction, data-deficient species are typically excluded from global and local conservation priorities, as well as funding schemes. The number of data-deficient species will greatly increase as the IUCN Red List becomes more inclusive of poorly known and speciose groups. A strategic approach is urgently needed to enhance the conservation value of data-deficient assessments. To develop this, we reviewed 2879 data-deficient assessments in 6 animal groups and identified 8 main justifications for assigning data-deficient status (type series, few records, old records, uncertain provenance, uncertain population status or distribution, uncertain threats, taxonomic uncertainty, and new species). Assigning a consistent set of justification tags (i.e., consistent assignment to assessment justifications) to species classified as data deficient is a simple way to achieve more strategic assessments. Such tags would clarify the causes of data deficiency; facilitate the prediction of extinction risk; facilitate comparisons of data deficiency among taxonomic groups; and help prioritize species for reassessment. With renewed efforts, it could be straightforward to prevent thousands of data-deficient species slipping unnoticed toward extinction.
authors.affiliation: School of BioSciences, The University of Melbourne, Parkville, VIC 3010, Australia.
authors.forename: Lucie M
authors.initials: LM
authors.lastname: Bland
authors.affiliation: Institute of Zoology, Zoological Society of London, Regent's Park, London, NW1 4RY, U.K.
authors.forename: Jon
authors.initials: J
authors.lastname: Bielby
authors.affiliation: School of Geography, Planning and Environmental Management, University of Queensland, St. Lucia, QLD, 4072, Australia.
authors.forename: Stephen
authors.initials: S
authors.lastname: Kearney
authors.affiliation: Division of Biology, Imperial College London, Silwood Park, Ascot, SL5 7PY, U.K.
authors.forename: C David L
authors.initials: CDL
authors.lastname: Orme
authors.affiliation: School of Geography, Planning and Environmental Management, University of Queensland, St. Lucia, QLD, 4072, Australia.|Wildlife Conservation Society, Global Conservation Programs, Bronx, NY, 10460, U.S.A.
authors.forename: James E M
authors.initials: JEM
authors.lastname: Watson
authors.affiliation: Centre for Biodiversity and Environment Research, University College London, Gower Street, London, WC1 E6BT, U.K.
authors.forename: Ben
authors.initials: B
authors.lastname: Collen
mesh_terms: D000818:Animals; D003247:Conservation of Natural Resources; D003625:Data Collection; D056727:Endangered Species; D053476:Extinction, Biological; D012306:Risk; D035501:Uncertainty
keywords: IUCN Red List; Lista Roja de la UICN; amphibians; anfibios; cangrejo de río; cangrejos de agua dulce; crayfish; extinction risk; freshwater crabs; mammals; mamíferos; odonatan; odonatos; reptiles; riesgo de extinción