Cold War spy satellite imagery is helping scientists track the decline of animals and their habitats in Kazakhstan over the past 50 years
- Images from the Cold War’s Corona programme imaged a region of Kazakhstan
- The photographs were declassified five years after the fall of the Iron Curtain
- Scientists have used them to track the impact of farming on the bobak marmot
- Found number of marmot burrows has dropped by 14% between 1968 and 2017
Images taken by US Cold War satellites have revealed the impact of farming on wildlife in the former Soviet state of Kazakhstan.
Pictures from the American Corona programme show that 50 years of agricultural expansion in the region has negatively impacted ground squirrels.
High-resolution photos from the spy satellites happened across the burrows of bobak marmots, a key species in the ecosystem of the former Soviet republic.
Comparison with modern satellite photos reveals a 14 per cent decline in marmot burrows between 1968 and 2017.
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Images taken by US Cold War satellites (left) have been compared with modern looks at the same land (right). Researchers found a decline in the number of bobak marmot burrows in a 23,000 square mile region of north Kazakhstan. Yellow circles are individual burrows
Pictures of what is now modern-day Kazakhstan by the American Corona programme show that over 50 years agricultural growth in the region has negatively impacted ground squirrels. Catalina Munteanu, lead researcher of the study, found the number of marmot burrows has dropped by 14 per cent between 1968 and 2017
Over the last half a century, farmers have expanded their range and infringed upon the natural habitat of the keystone species.
To map the long-term impact of this human expansion, researchers from the Humboldt University Berlin turned to declassified spy images as an unexpected source of data.
They were taken in 1968 and 1969 by the US as part of reconnaissance missions and declassified in 1996, after the fall of the Iron Curtain and five years after Kazakhstan gained independence.
American intelligence forces were scouring nuclear weapons but the German scientists were not interested in war, they were looking for marmot burrows.
A 23,000 square mile (60,000 square km) corner of northern Kazakhstan was focused on and the images from the 60s compared with modern images taken between 1999 and 2017.
As well as revealing the loss of biodiversity, the study also found that marmots are homebodies and live in the same burrows for several generations (stock)
Catalina Munteanu, lead researcher of the study, found the number of marmot burrows has dropped by 14 per cent between 1968 and 2017 in this study area area, roughly half the size of England.
This was driven mostly by the conversion of wild regions into arable land. The study found that, over 50 years, grassland was reduced by around six per cent.
In contrast, cropland increased over the study period, but more than a third of the land was still fallow or abandoned.
The researchers say the land was rapidly converted to farmland following crippling food shortages in the wake of World War Two.
In the regions of the 23,000 square mile study area that were converted to farmland, burrows declined by around 60 per cent.
As well as revealing the loss of biodiversity, the study also found that marmots are homebodies and live in the same burrows for several generations.
‘I was really surprised to find that the marmots were using the exact same burrows for half a century long,’ Dr Munteanu told New Scientist.
Marmots only have a lifespan of around six years, which means around eight generations of the animals lived in the same burrows.
The full findings are available in the journal Proceedings of the Royal Society B.