Plants and animals that don’t have enough data to be properly assessed appear to be at twice the risk of extinction than those that have been evaluated, meaning more species could be wiped out from the planet than previously thought, a study has found. investigation warned.
Researchers looked at the extinction risk of species assessed on the Red List of Threatened Species and found that 56% of species in the insufficient data (DD) category were threatened, compared to 28% of species assessed.
A species is considered DD when there isn’t enough data on their distribution or population, and these species are “generally ignored” in studies analyzing impacts on biodiversity, researchers wrote in the paper, published in Communications Biology. Created by the International Union for Conservation of Nature (IUCN), the Red List is used by governments to figure out which species should be prioritized for conservation.
The IUCN assesses more than 140,000 species based on criteria such as population size, trends and threats. There are 20,000 DD species on the red list and policymakers often consider them to be of least concern, but this study found that a much higher proportion of these species are threatened. Researchers said 85% of DD amphibians were at risk, as were more than half of mammals, reptiles and insects.
Species can be DD because there are very few, sightings are rare or they can be cryptic species making it difficult to estimate their population. To overcome these problems, researchers developed an algorithm that predicted the likelihood of species facing extinction based on key factors they knew, such as the global distribution of those species, climatic conditions, land use change, pesticide use, and threats from invasive species. Researchers ran the algorithm on DD species when their geographic distribution was known, which was the case for about 38% of them.
Some DD species with a very high chance of being at risk included the Sierra Miahuatlan spikethumb frog, which has a 95% chance of being threatened with extinction, as does the Sholai night frog, and a Mexican fish called the Ajijic silverside.
Previous studies have looked at the extinction risk of DD species, but this is the most far-reaching, looking at 21 taxonomic groups — still “a tiny fraction of what exists in the world,” said lead researcher Jan Borgelt of the Norwegian University of Science. and Technology (NTNU).
Borgelt said: “In general, what is more striking is that in almost all land and coastal regions of the world, the average extinction risk would be higher if we accounted for species with lack of data.” If DD species were included, 33% of Red List species would be threatened, as opposed to 28%, the algorithm predicted.
Central Africa, South Asia and Madagascar are the regions with the highest number of high-risk DD species, although researchers haven’t looked at why this might be the case. As many as half of the DD marine species living in coastal areas are threatened with extinction.
Prof Jane Hill of the University of York, who is also a trustee of the British Ecological Society and was not involved in the study, said: “The study is important because the approach they use [machine learning methods] could be applied to many more species.”
About 18,000 invertebrates have been assessed for extinction on the Red List, but 27% are DD. The rate at which insects are dying out is eight times faster than that of birds, mammals and reptiles, according to analysis published last year, with known declines likely to be the “tip of the iceberg.” Research has shown that vertebrates get nearly 500 times more money for each species than invertebrates, which are considered less “charismatic.”
Hill said: “It has long been recognized that the IUCN red list approach targets only a small fraction of all species on Earth and should be more representative. So while this study provides more information on DD species, we still know very little about most species on Earth.”
Some of the Endangered DD Species
An example where the algorithm can be used is with the newly recognized The whale of rice, which scientists for almost a decade believed could be a species, though it took years to gain official recognition. Now there are only about 50 left in the area affected by the Deepwater Horizon oil spill, where there is a lot of boat traffic and oil and gas extraction. There is no local outcry because no one knows it exists, says marine researcher Dr Chris Parsons of the University of Exeter, who believes the DD category should be given ‘presumed threatened’ status. He said: “If immediate precautions had been taken years ago when they first suspected a new species, it could have necessitated an immediate investigation and emergency measures initiated that could have prevented the species from becoming critically endangered.” became.”
from 23 beaked whale species on the red list, seven are DD. They spend a lot of time underwater (their dives can last up to three hours) and are difficult to see in the wild, yet they are at risk from a number of threats, including man-made noise pollution in the ocean that could cause massive strandings . The data on beaked whales is so poor that the algorithm cannot estimate the risk they are at.
Indo-Pacific Humpback Dolphins in Southeast Asia were considered DD for a long time, so there was no money and little interest in studying them. They are now considered “near threatened” and have become the official mascot of Hong Kong, and are also listed under the US Endangered Species Act, which supports international conservation efforts.
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