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As the world’s nations prepare to set new goals for protecting biodiversity, Yale researchers have identified where data gaps continue to limit effective conservation decisions.

In a new study, a team of researchers created maps and assessed regional trends in how well existing species data are able to represent the distribution of 31,000 terrestrial vertebrates worldwide and therefore help inform policies and actions for sustaining biodiversity and its benefits.

“These maps highlight the most rewarding opportunities for citizen scientists, and government agencies, and scientists to support biodiversity monitoring and help close critical knowledge gaps,” said Walter Jetz, professor of ecology and evolutionary biology and of the environment, director of the Yale Center for Biodiversity and Global Change (BGC), and senior author of the paper.

The study was published Aug. 10 in the journal PLOS Biology.

The need for such information is critical as environmental and policy leaders continue to create strategies to protect species diversity worldwide as part of the Convention on Biological Diversity, an international treaty with the aim of conserving and managing global biodiversity which is assessing progress towards those goals.

Jetz and his team have created one of the key tools used by world leaders to monitor, research, and create policies that protect species worldwide — the Map of Life.

In the new study, the researchers present a framework to help pinpoint where additional monitoring is most needed. While there has been a dramatic increase in the amount of data collected on vertebrate species in the past 20 years, they find, not all of this data has yielded new insights on biodiversity. For instance, data on bird species shared by citizen scientists and others tend to be redundant due to the popularity of certain species commonly found in highly populated areas. Most new data collected on birds are from the same species and places.

The analysis was conducted by Yale’s Ruth Oliver, an associate research scientist at the Center for Biodiversity and Global Change, Jetz, and colleagues.

Alarmingly, the study finds that data critical for characterizing biodiversity in many countries has levelled off or, in some cases, even decreased. According to the analysis, 42% of countries have inadequate information on vertebrate biodiversity and have seen either no increase or a decrease in data coverage. Only 17% of countries have achieved sufficient data coverage and also seen an increase in new information on species.

“We hope our work quantifying the tremendous complementary value of observations of underreported biodiversity can support more effective data collection going forward,” Oliver said. “It’s amazing how much we still don’t know about the known species on this planet.”

While the indices used in the study were used to demonstrate the biological diversity of terrestrial vertebrates, they can be readily updated as new data becomes available and expanded to other taxa, such as marine and invertebrate species. This work is supported by the Map of Life team and the results are available for exploration at mol.org/indicators/coverage.

View the article on Yale News

Ecologists involved in mapping all life on Earth have now taken the next step: predicting where the life we don’t know about is waiting to be discovered. As a first pass, they have created an interactive map showing diversity hot spots with the richest potential for new mammal, bird, reptile, and amphibian species. They describe their results today in Nature Ecology & Evolution.

“Unknown species are usually left out of conservation planning, management, and decision-making,” says co-author Mario Moura, an ecologist at the Federal University of Paraíba. “If we want to improve biodiversity conservation worldwide, we need to better know its species.”

It never sat well with Moura that an estimated 85% of Earth’s species are still undescribed. So, in 2018, this newly minted Ph.D. in ecology teamed up with ecologist Walter Jetz at Yale University to come up with a way to better predict where those unknowns are. “The chances of being discovered and described early are not equal among species,” Moura explains. For example, large mammals living near people are much more likely to have been documented by scientists than tiny frogs living in a remote jungle.

View the article on Science

In 1983, around 40,000 Nile lechwes (Kobus megaceros) roamed South Sudan and eastern Ethiopia. By 2060, this endangered population of African antelope may be on the brink of extinction. The cause? Loss of wild habitat.

This antelope is just one of hundreds of species that may be imperiled in the next four to five decades, according to a recent NASA-funded study. Researchers from Yale University examined the habitats of 19,400 species to learn how they might be affected by human land-use and encroachment, such as urban development and deforestation. They found that habitats for nearly 1,700 bird, mammal, and amphibian species are expected to shrink about 6 to 10 percent per decade by 2070, greatly increasing the risk of extinction for these animals.

“We all want to see economic progress and development, and that necessarily implies further human-induced changes to landscapes,” said Walter Jetz, co-author of the study and professor of ecology at Yale. “But unless potential impacts of this land use on biodiversity are known and addressed in some form, the long-term consequences could lead to species forever lost for future generations.”

The maps on this page show the potential decrease of suitable habitats for two vulnerable species. The map above shows the habitat change for the Nile lechwes from 2015 (left) to 2070 (right). The antelope species could lose approximately 70 percent of its suitable habitat and become “critically endangered” by 2070.

The map below shows the habitat of Oreophryne monticola, a frog endemic to Indonesia. The frog is currently listed as “endangered” and is predicted to lose more than 50 percent of its habitat in Lombok and Bali by 2070.

“If a country is projected to see a lot of change of swamps or forest to agriculture, this a good predictor that some species in that area are in jeopardy,” said Jetz. “That doesn’t mean these species are necessarily going to go extinct, but they are going to be put under pressure.”

According to the study, amphibians will be the most affected by human land use, followed by birds and mammals. Geographically, species living in South America, Southeast Asia, Central and East Africa, and Mesoamerica are expected to experience the most habitat loss and the greatest increase of extinction risk.

To make these predictions, Jetz and co-author Ryan Powers created a model that allowed them to analyze 2015 habitat conditions of about 19,400 species under anticipated changes in land-use in these areas.

To first estimate the area of suitable habitats in 2015, the team used several remote sensing layers. Elevation data came from Shuttle Radar Topography Mission (SRTM) and the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER). Tree cover data came from the Global Forest Change data set, which uses Landsat data to document global tree cover gains and losses.

The researchers then ran a model combining this habitat suitability information with future land-cover projections from the Land Use Harmonization data set in order to estimate decadal changes from 2015 to 2070. They ran the numbers under four different socioeconomic scenarios that would bring variations in land use. (The maps on this page show the “middle-of-the-road” economic scenario and assume no land will be recovered once destroyed.) Even in the best cases, many species are predicted to experience habitat losses by 2070.

“Even though we might see certain losses into the future no matter what we do,” said Jetz, “we can adjust to have the greatest chance of preserving life.” The study could help future conservation efforts by local, national, and international organizations.

The research by Jetz and Powers feeds into an initiative called the Map of Life, a NASA-funded public web platform designed to integrate large amounts of biodiversity and environmental data from researchers and citizen scientists. The global database aims to support a worldwide monitoring of species distributions.

NASA Earth Observatory images by Lauren Dauphin, using data from Powers, Ryan, et al. (2019).

View article on NASA Earth Observatory