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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).

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As humans continue to expand our use of land across the planet, we leave other species little ground to stand on. By 2070, increased human land-use is expected to put 1,700 species of amphibians, birds, and mammals at greater extinction risk by shrinking their natural habitats, according to a study by Yale ecologists published in Nature Climate Change.

To make this prediction, the ecologists combined information on the current geographic distributions of about 19,400 species worldwide with changes to the land cover projected under four different trajectories for the world scientists have agreed on as likely. These potential paths represent reasonable expectations about future developments in global society, demographics, and economics.

“Our findings link these plausible futures with their implications for biodiversity,” said Walter Jetz, co-author and professor of ecology and evolutionary biology and of forestry and environmental studies at Yale. “Our analyses allow us to track how political and economic decisions — through their associated changes to the global land cover — are expected to cause habitat range declines in species worldwide.”

"While biodiversity erosion in far-away parts of the planet may not seem to affect us directly, its consequences for human livelihood can reverberate globally." -Walter Jetz

The study shows that under a middle-of-the-road scenario of moderate changes in human land-use about 1,700 species will likely experience marked increases in their extinction risk over the next 50 years: They will lose roughly 30-50% of their present habitat ranges by 2070. These species of concern include 886 species of amphibians, 436 species of birds, and 376 species of mammals — all of which are predicted to have a high increase in their risk of extinction.

Among them are species whose fates will be particularly dire, such as the Lombok cross frog (Indonesia), the Nile lechwe (South Sudan), the pale-browed treehunter (Brazil) and the curve-billed reedhaunter (Argentina, Brazil, Uruguay) which are all predicted to lose around half of their present day geographic range in the next five decades. [These projections and all other analyzed species can be examined at the Map of Life website] (https://mol.org/species/projection/landuse).

“The integration of our analyses with the Map of Life can support anyone keen to assess how species may suffer under specific future land-use scenarios and help prevent or mitigate these effects,” said Ryan P. Powers, co-author and former postdoctoral fellow in the Jetz Lab at Yale.

Species living in Central and East Africa, Mesoamerica, South America, and Southeast Asia will suffer the greatest habitat loss and increased extinction risk. But Jetz cautioned the global public against assuming that the losses are only the problem of the countries within whose borders they occur.

“Losses in species populations can irreversibly hamper the functioning of ecosystems and human quality of life,” said Jetz. “While biodiversity erosion in far-away parts of the planet may not seem to affect us directly, its consequences for human livelihood can reverberate globally. It is also often the far-away demand that drives these losses — think tropical hardwoods, palm oil, or soybeans — thus making us all co-responsible.”

The study was funded by grants from the National Science Foundation, the Natural Sciences and Engineering Research Council of Canada, and the National Aeronautics and Space Administration.

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The International Cooperation for Animal Research Using Space, or ICARUS, will be flying closer to the sun than ever when a pair of Russian cosmonauts installs the antennae for its state-of-the-art animal tracking system on the exterior of the International Space Station on Aug. 15. The installation will be one small step for the cosmonauts and one giant leap for Yale biodiversity research.

Thanks to the recently founded Max Planck-Yale Center (MPYC) for Biodiversity Movement and Global Change, Yale and U.S.-based biodiversity researchers will be among the first to make use of the big data that this groundbreaking scientific instrument will be collecting by early 2019.

For the past 16 years, ICARUS has been simultaneously developing the tiniest transmitters (by 2025, the team hopes to scale down solar-powered backpacks enough to fit them on desert locusts) and some of the most massive antennae (the equipment that the cosmonauts will be installing). Together, these two new technologies will give biodiversity researchers an unprecedented, extraterrestrial perspective on the lives of some of Earth’s smallest and most mobile creatures, such as fruit bats, baby turtles, parrots, and songbirds.

“The system represents a quantum leap for the study of animal movements and migration, and will enable real-time biodiversity monitoring at a global scale,” said Walter Jetz, professor of ecology and evolutionary biology at Yale and co-director of the MPYC.

"I expect ICARUS to exceed what has existed to date by at least an order of magnitude and someday potentially several orders." -walter jetz

“In the past, tracking studies have been limited to, at best, a few dozen simultaneously followed individuals, and the tags were large and readouts costly,” added Jetz. “In terms of scale and cost, I expect ICARUS to exceed what has existed to date by at least an order of magnitude and someday potentially several orders. This new tracking system has the potential to transform multiple fields of study.”

Even with the limited tracking technology available, biodiversity researchers have already been able to predict volcanic eruptions by tracking the movements of goat herds and understand impacts of climate change by following migration changes in birds. This new space station-based system will allow researchers to see “not only where an animal is but also what it is doing,” explained Martin Wikelski, chief strategist for ICARUS, director of the Max Planck Center for Ornithology, and co-director with Jetz of the MPYC.

“At a global scale, we will be able to monitor individual animal behaviors as well as get a grasp of their intricate life histories and interactions with each other,” said Wikelski. In addition to positional coordinates, the transmitters are able to capture each animal’s acceleration, alignment to the magnetic field of Earth, and moment-to-moment environmental conditions, including ambient temperature, air pressure, and humidity.

The technology provides an exciting tool to monitor changing wildlife and the connectivity of landscapes for conservation and public health, explained Jetz. Researchers will be able to apply this new language of mass animal movement to everything from greater forewarning of geological disasters, such as earthquakes and volcanic eruptions, to monitoring the next potential disease outbreak in humans. For example, Wikelski plans to use the new system to advance his own project of tracking the movement of African fruit bats as sentinels for finding the hosts of the Ebola virus. (Fruit bats have antibodies against, but do not transmit, this deadly disease.)

“Tracked animals can act as intelligent sensors and biological sentinels and in near real-time inform us about the biodiversity effects of ongoing environmental change,” explained Jetz.

By the beginning of 2019, Wikelski and colleagues will have 1,000 transmitters in the field, but eventually, they hope to grow that number to 100,000. Every time a transmitter enters the International Space Station’s beam — roughly four times daily — it may send up a data packet of 223 bytes. From there, the data will be relayed back to the ground station and subsequently distributed to research teams. All data — except sensitive conservation data such as rhino locations — will also be published on the publicly accessible database MoveBank, and will inform maps and trends in Map of Life, a web-based initiative headed by Jetz that integrates global biodiversity evidence.

As with all fields of scientific research, however, the data are only as good as their processing and analysis. MPYC will be the primary initial interpreter of the big data harvested by the ICARUS satellite. Fortunately, Jetz notes, with Yale’s investment in integrative data science as a research priority, MPYC can handle the big data sets that the ICARUS tracking system generates.

“Going back to my own Ph.D. work observing and tracking nocturnal birds in Africa with much inferior technology,” said Jetz, “I was always driven by the wish to document and understand biodiversity from the level of the individual up to the global scale.”

“The new technology will allow us to put the bigger picture together,” Jetz continued. “Thanks to the near-global scale of ICARUS and satellite-based remote sensing of the environment, we are finally able to connect individual behaviors and decisions with the use of space and environments at large scales. Our collaboration with Max Planck and ICARUS is a wonderful enabler of and complement to our work at Yale.”

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