Washington: An international study has provided the first global assessment of all terrestrial vertebrate species yet to be declared extinct, identifying over 500 species as ‘lost’. This species has not been seen for over 50 years.
Researchers reviewed information on 32,802 species on the International Union for Conservation of Nature’s Red List of Threatened Species (IUCN Red List) and identified 562 lost species. Their findings are published in the journal Animal Conservation.
The IUCN Red List defines extinct as “when there is no reasonable doubt that the last individual of a species is dead”, which can be difficult to verify. According to Arne Mooers, professor of biodiversity at Simon Fraser University and co-author of the study, the Red List classifies 75 of these 562 lost species as “probably extinct”. The researchers note that the existence of many species with uncertain conservation status may become increasingly problematic as the extinction crisis deepens and more species go extinct.
A total of 311 species of terrestrial vertebrates have been declared extinct since 1500, meaning 80% more species are considered lost than those declared extinct.
Reptiles led the way with 257 species considered lost, followed by 137 species of amphibians, 130 species of mammals and 38 species of birds. Most of these lost animals were last seen in megadiverse countries such as Indonesia (69 species), Mexico (33 species), and Brazil (29 species).
Not surprisingly, this concentration is significant, according to the researchers. “The fact that most of these lost species are found in tropical megadiverse countries is concerning, given that these countries are expected to see the highest number of extinctions over the next few decades,” says the study’s lead author. , Tom Martin, of Paignton Zoo in the UK.
Mooers, who anchored the study, says: “While the theoretical estimates of ongoing ‘extinction rates’ are good and good, it seems best to look carefully for the actual species.”
Gareth Bennett, an SFU undergraduate who did much of the data combing, adds, “We hope this simple study will help make these lost species a priority for future research.
The authors suggest that future survey efforts focus on identified “hotspots” where the existence of many species remains uncertain. More funding would be needed to support this targeted hotspot fieldwork, either to rediscover lost species or to remove reasonable doubt that a particular lost species still exists.