Image of a couple of tigers in a snowy territory. PXHERE.com Francisco Martín León 03/05/2024 16:00 6 min
Tigers are just one of the vulnerable large mammals whose habitats NASA is helping to track from space.
“Satellites observe vast areas of the Earth’s surface on daily or weekly schedules“, said Keith Gaddis, director of the ecological conservation program at NASA Headquarters in Washington. “That helps scientists monitor habitats that would be logistically challenging and time-consuming to study from the ground, crucial for animals like tigers that roam large territories.s”.
Loss of tiger habitat
In the last two centuries, tigers have lost at least 93 percent of their historic range, which once spanned Eurasia. Today, big cats They live in only 10 countries, mostly in Asia. Scientists estimate that only between 3,700 and 5,500 tigers remain in the wild, although that is up from an estimated low of 3,200 individuals in 2010.
In a recent analysis, researchers They reviewed more than 500 studies carried out between 2001 and 2020 which contained data about tigers and their habitat. The team discovered that the area where they are known to live big cats decreased by 11 percent in the last two decadesfrom approximately 1,025,000 square kilometers in 2001 to approximately 912,000 square kilometers in 2020.
Tiger habitat status as of January 2020 with respect to its native range. POT
Southeast Asian countries were among the most affected. Over the last 20 years, big cats disappeared from three nations: Cambodia, Vietnam and Laos, the researchers reported. Those nations also saw declines in habitat, although the team said it’s unclear whether habitat loss alone is behind the decline in tiger numbers. Animals may also be illegally hunted and killed or decline as their food sources disappear.
Other countries in the region, such as Thailand, also suffered a loss of tiger habitat. But in some parts of eastern Thailand and in a large conservation area called the Western Forest Complex, the country’s tigers are well protected. These areas could be sources of tigers that may disperse to other areas, according to the study, published in December 2023 in Frontiers in Conservation Science.
Directed by the Wildlife Conservation Society (WCS) and funded by NASA’s Conservation Ecology program, the team developed a tool that uses Google Earth Engine and NASA Earth observations to monitor changes in tiger habitat. The goal: to help conservation efforts in near real time, using data from VIIRS and MODIS sensors and Landsat satellites.
The map at the top of this page shows the status of tiger habitat as of January 2020 with respect to its native distribution area (tan). The orange areas show areas of suitable habitat where it is known that tigers are found. Those are areas that need to be conserved and expanded, including prey populations, the team concluded. Green areas are “empty forests” where tigers are not known to live recentlybut because these areas were suitable for tigers in the past and are still large enough to support a tiger population, they are potential landscapes for tiger restoration. The remaining colors show where the habitat is potentially suitable but the residence of the tiger (brown) and areas where the habitat is too fragmented to support tigers (black) are unknown.
Observe the large expanses of potential habitat for tiger restoration (green). If tigers could reach those areas, either through natural dispersal or active reintroduction, and assuming they had enough food to survive there, they could “increase the tigers’ land base by 50 percent“the scientists reported.
“It wasn’t long ago that people thought tigers were going to become extinct in the wild. But there is still much more room for tigers in the world than even tiger experts thought.”said the lead author Eric Sanderson, former senior conservation ecologist at WCS and now vice president of urban conservation at the New York Botanical Garden. “We were only able to solve it because we gathered all this data from NASA and integrated it with information from the field“.
Picture of NASA Earth Observatory of Wanmei Liang using data from Sanderson, E., et al. (2023). History of Emily DeMarco/NASA Earth Sciences Division, Headquarters.
This entry was published in News on 03 May 2024 by Francisco Martín León