Migrations in motion

Screenshot of animated map (Dan Majka/The Nature Conservancy)

As Earth warms and climate patterns adapt in response, animals will be forced to move to survive. That usually means hightailing it to higher latitudes as equatorial areas become too hot and dry. Many species moved great distances as climates changed. Historically, this movement pattern has happened fluidly and naturally as climates have shifted, but now with human developments such as cities, highways and agriculture, critical animal migrations will be limited in surprising and troubling ways.

Based on a 2013 study in Ecology Letters that considered the likely movement patterns of nearly 3,000 species under climate change the University of Washington and the Nature Conservancy have created an animated map showing where mammals, birds and amphibians are projected to move in the Western Hemisphere in response to climate change. The visualization draws upon flow models from electronic circuit theory, taking inspiration from existing visualizations of wind flow across the U.S.

The map is color-coded to depict separate movement patterns for mammals, birds and amphibians. The animations show a mass exodus toward northern regions, with empty black zones showing where large cities or landscape features like the Great Lakes block migration. Each dot and subsequent streaking line show the accumulation of species' movement, not just one animal's future migration. 

The researchers were surprised to see how clearly migration routes appeared once the data were visualized. They knew from the data that the Appalachians and the Rocky Mountains were important movement areas, but once the data were animated on a map, those routes were clearly visible. In South America the most striking pattern is a projected movement of species west and south out of the Amazon.

This is the best visualization of any of these studies we've done. It's much more compelling than our static maps. The flow diagram really makes the data much more accessible.