Imagine taking your first trip into space. You’re about to turn to the window and look down at Earth from above for the very first time – what would you be hoping to see?
Well, some scientists are looking down in the hope of spotting a beaver.
OK, not exactly. Actually, they’re using satellite imagery to locate beaver ponds – because researchers have discovered that these busy, dam-building amphibious rodents could help to mitigate the impact of extreme weather (in particular, drought) on Earth.
Beavers build dams to slow the flow of water through a river. The purpose is to create pools (or ponds) where they can construct small islands or domes that serve as their homes – the islands are dry, giving them a place to rest, care for their young, and store their food.
Because the islands are well away from the bank of the river, they’re safe from land animals; and the beavers can also dig entrances to these homes underwater.
This work has benefits for the environment and other animals, too. The landscapes that beavers create help to reduce downstream flooding, clean the water, and increase water retention – which supports the environment around them in times of drought.
Stick with us – we’ll get to the space tech part, we promise.
Wired recently reported that a team of scientists and Google engineers have been working on an algorithm that can identify beaver infrastructure on satellite images.
Because understanding beaver habitats (and the way they change the environment around them) could help to rejuvenate drought-beaten landscapes.
Speaking about California specifically, Kristen Wilson (Lead Forest Scientist at Nature Conservancy) told Wired, “All of our efforts in the state should be taking advantage of this powerful mapping tool. It’s really exciting.”
The mapping tool has been developed by a team led by Eddie Corwin (formerly part of Google’s real-estate sustainability group). He wanted to enable his organisation to enable better stewardship of the waterways around them, and during his research, he discovered that beaver wetlands can hold millions of gallons of water and have a very real impact on the environments connected to them. Corwin got his friend and sustainability consultant Dan Ackerstein on board, and together they gained Google backing for their idea to develop a technological system for mapping beaver ponds.
They called their model the Earth Engine Automated Geospatial Elements Recognition, or EEAGER.
As detailed in this research article, it’s a neural network that detects beaver habitats in aerial and satellite imagery. It’s been trained on 13,344 known beaver dam locations in the western United States, along with 56,728 nearby locations without beaver dams. The model ‘favours recall over precision’ at present, which enables a more comprehensive catalogue of beaver dams – but also drives in a relatively high number of false positives that have to be manually removed.
“These results have far-reaching implications,” the authors note, “for monitoring of beaver-based river restoration, as well as potential applications detecting other complex landforms.”
In a nutshell, the model can speed up the process of identifying and locating beaver complexes (and potentially other landscape features in the future, as well).
But the implications of this are important. Because a better understanding of beaver landscapes could bring drought landscapes back to life – supporting the process of beaver restoration, which in turn drives better land water storage and mitigates the impact of drought.
Peering down at beavers from space isn’t a frivolous activity. It’s a beautiful example of the way that technology and natural processes can come together to support the restoration of natural environments – and we’re excited to see the use cases that emerge when the EEAGER goes public.